Added Prometheus support

Removed old metrics / status endpoints and internal counters

CHANGES.md

@@ -4,6 +4,9 @@
 
 (dev branch; still in testing)
 
+* Added Prometheus metrics support
+* Removed /monitor websocket interface
+* Removed /status and /status.json pages
 * Support "closest" matching (instead of geo/asn labels) for A and AAAA records (Alex Bligh)
 * Support for GeoIP2 databases (including IPv6 data and ASN databases)
 * "Pluggable" targeting data support

Gopkg.lock

@@ -7,6 +7,12 @@
   packages = ["."]
   revision = "f9bd360d00b902548fbb80837aef90dca2c8285e"
 
+[[projects]]
+  branch = "master"
+  name = "github.com/beorn7/perks"
+  packages = ["quantile"]
+  revision = "3a771d992973f24aa725d07868b467d1ddfceafb"
+
 [[projects]]
   name = "github.com/davecgh/go-spew"
   packages = ["spew"]
@@ -31,6 +37,12 @@
   ]
   revision = "fb250ae94fbe10f86b4f1a9b70a19925da3410b9"
 
+[[projects]]
+  name = "github.com/golang/protobuf"
+  packages = ["proto"]
+  revision = "925541529c1fa6821df4e44ce2723319eb2be768"
+  version = "v1.0.0"
+
 [[projects]]
   branch = "master"
   name = "github.com/hpcloud/tail"
@@ -66,6 +78,12 @@
   packages = ["."]
   revision = "7cafcd837844e784b526369c9bce262804aebc60"
 
+[[projects]]
+  name = "github.com/matttproud/golang_protobuf_extensions"
+  packages = ["pbutil"]
+  revision = "3247c84500bff8d9fb6d579d800f20b3e091582c"
+  version = "v1.0.0"
+
 [[projects]]
   branch = "master"
   name = "github.com/miekg/dns"
@@ -96,11 +114,41 @@
   revision = "792786c7400a136282c1664665ae0a8db921c6c2"
   version = "v1.0.0"
 
+[[projects]]
+  name = "github.com/prometheus/client_golang"
+  packages = [
+    "prometheus",
+    "prometheus/promhttp"
+  ]
+  revision = "c5b7fccd204277076155f10851dad72b76a49317"
+  version = "v0.8.0"
+
 [[projects]]
   branch = "master"
-  name = "github.com/rcrowley/go-metrics"
-  packages = ["."]
-  revision = "d932a24a8ccb8fcadc993e5c6c58f93dac168294"
+  name = "github.com/prometheus/client_model"
+  packages = ["go"]
+  revision = "99fa1f4be8e564e8a6b613da7fa6f46c9edafc6c"
+
+[[projects]]
+  branch = "master"
+  name = "github.com/prometheus/common"
+  packages = [
+    "expfmt",
+    "internal/bitbucket.org/ww/goautoneg",
+    "model"
+  ]
+  revision = "d811d2e9bf898806ecfb6ef6296774b13ffc314c"
+
+[[projects]]
+  branch = "master"
+  name = "github.com/prometheus/procfs"
+  packages = [
+    ".",
+    "internal/util",
+    "nfs",
+    "xfs"
+  ]
+  revision = "8b1c2da0d56deffdbb9e48d4414b4e674bd8083e"
 
 [[projects]]
   branch = "master"
@@ -128,8 +176,7 @@
     "internal/iana",
     "internal/socket",
     "ipv4",
-    "ipv6",
-    "websocket"
+    "ipv6"
   ]
   revision = "5f9ae10d9af5b1c89ae6904293b14b064d4ada23"
 
@@ -174,6 +221,6 @@
 [solve-meta]
   analyzer-name = "dep"
   analyzer-version = 1
-  inputs-digest = "af25838ce6464813e6ddb5cc8c75339d8ed45fd80e3bfa2ad49f4683267a155e"
+  inputs-digest = "b125de5fd655b7a23552eec6fb2c6f6b65fcd64a26c899c1737426bdcf661bde"
   solver-name = "gps-cdcl"
   solver-version = 1

Makefile

@@ -14,7 +14,7 @@ docker-test: .PHONY
 	# test that we don't have missing dependencies
 	docker run --rm -v `pwd`:/go/src/github.com/abh/geodns \
 		-v /opt/local/share/GeoIP:/opt/local/share/GeoIP \
-		golang:1.10-alpine3.7 \
+		golang:1.10.1-alpine3.7 \
 		go test ./...
 
 devel:
@@ -26,7 +26,9 @@ bench:
 TARS=$(wildcard geodns-*-*.tar)
 
 push: $(TARS) tmp-install.sh
-	rsync -avz tmp-install.sh $(TARS)  x3.dev:webtmp/2018/02/
+	#rsync -avz tmp-install.sh $(TARS)  x3.dev:webtmp/2018/04/
+	rsync tmp-install.sh $(TARS) $(DIST)/$(DISTSUB)/
+	$(DIST)/push
 
 builds: linux-build linux-build-i386 freebsd-build push
 

geodns.go

@@ -66,7 +66,7 @@ var (
 	flagLogFile      = flag.String("logfile", "", "log to file")
 	flagPrivateDebug = flag.Bool("privatedebug", false, "Make debugging queries accepted only on loopback")
 
-	flagShowVersion = flag.Bool("version", false, "Show dnsconfig version")
+	flagShowVersion = flag.Bool("version", false, "Show GeoDNS version")
 
 	cpuprofile = flag.String("cpuprofile", "", "write cpu profile to file")
 	memprofile = flag.String("memprofile", "", "write memory profile to this file")
@@ -215,9 +215,6 @@ func main() {
 		}
 	}
 
-	mon := monitor.NewMonitor(serverInfo)
-	go mon.Run()
-
 	srv := server.NewServer(serverInfo)
 
 	if qlc := Config.QueryLog; len(qlc.Path) > 0 {

http.go

@@ -1,20 +1,15 @@
 package main
 
 import (
-	"encoding/json"
 	"fmt"
-	"html/template"
 	"io"
 	"log"
 	"net/http"
-	"runtime"
-	"sort"
 	"strconv"
-	"time"
 
 	"github.com/abh/geodns/monitor"
 	"github.com/abh/geodns/zones"
-	metrics "github.com/rcrowley/go-metrics"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 )
 
 type httpServer struct {
@@ -44,27 +39,6 @@ func (s ratesByCount) Less(i, j int) bool {
 	return ic > jc
 }
 
-type histogramData struct {
-	Max    int64
-	Min    int64
-	Mean   float64
-	Pct90  float64
-	Pct99  float64
-	Pct999 float64
-	StdDev float64
-}
-
-func setupHistogramData(met metrics.Histogram, dat *histogramData) {
-	dat.Max = met.Max()
-	dat.Min = met.Min()
-	dat.Mean = met.Mean()
-	dat.StdDev = met.StdDev()
-	percentiles := met.Percentiles([]float64{0.90, 0.99, 0.999})
-	dat.Pct90 = percentiles[0]
-	dat.Pct99 = percentiles[1]
-	dat.Pct999 = percentiles[2]
-}
-
 func topParam(req *http.Request, def int) int {
 	req.ParseForm()
 
@@ -83,14 +57,14 @@ func topParam(req *http.Request, def int) int {
 }
 
 func NewHTTPServer(mm *zones.MuxManager, serverInfo *monitor.ServerInfo) *httpServer {
+
 	hs := &httpServer{
 		zones:      mm,
 		mux:        &http.ServeMux{},
 		serverInfo: serverInfo,
 	}
-	hs.mux.HandleFunc("/status", hs.StatusHandler())
-	hs.mux.HandleFunc("/status.json", hs.StatusJSONHandler())
 	hs.mux.HandleFunc("/", hs.mainServer)
+	hs.mux.Handle("/metrics", promhttp.Handler())
 
 	return hs
 }
@@ -104,126 +78,6 @@ func (hs *httpServer) Run(listen string) {
 	log.Fatal(http.ListenAndServe(listen, &basicauth{h: hs.mux}))
 }
 
-func (hs *httpServer) StatusJSONHandler() func(http.ResponseWriter, *http.Request) {
-
-	info := serverInfo
-
-	return func(w http.ResponseWriter, req *http.Request) {
-
-		zonemetrics := make(map[string]metrics.Registry)
-
-		for name, zone := range hs.zones.Zones() {
-			zone.Lock()
-			zonemetrics[name] = zone.Metrics.Registry
-			zone.Unlock()
-		}
-
-		type statusData struct {
-			Version   string
-			GoVersion string
-			Uptime    int64
-			Platform  string
-			Zones     map[string]metrics.Registry
-			Global    metrics.Registry
-			ID        string
-			IP        string
-			UUID      string
-			Groups    []string
-		}
-
-		uptime := int64(time.Since(info.Started).Seconds())
-
-		status := statusData{
-			Version:   info.Version,
-			GoVersion: runtime.Version(),
-			Uptime:    uptime,
-			Platform:  runtime.GOARCH + "-" + runtime.GOOS,
-			Zones:     zonemetrics,
-			Global:    metrics.DefaultRegistry,
-			ID:        hs.serverInfo.ID,
-			IP:        hs.serverInfo.IP,
-			UUID:      hs.serverInfo.UUID,
-			Groups:    hs.serverInfo.Groups,
-		}
-
-		b, err := json.Marshal(status)
-		if err != nil {
-			http.Error(w, "Error encoding JSON", 500)
-			return
-		}
-		w.Header().Set("Content-Type", "application/json")
-		w.Write(b)
-		return
-	}
-}
-
-func (hs *httpServer) StatusHandler() func(http.ResponseWriter, *http.Request) {
-
-	type statusData struct {
-		Version  string
-		Zones    rates
-		Uptime   DayDuration
-		Platform string
-		Global   struct {
-			Queries         metrics.Meter
-			Histogram       histogramData
-			HistogramRecent histogramData
-		}
-		TopOption int
-	}
-
-	return func(w http.ResponseWriter, req *http.Request) {
-
-		topOption := topParam(req, 10)
-
-		rates := make(rates, 0)
-
-		for name, zone := range hs.zones.Zones() {
-			count := zone.Metrics.Queries.Count()
-			rates = append(rates, &rate{
-				Name:    name,
-				Count:   count,
-				Metrics: zone.Metrics,
-			})
-		}
-
-		sort.Sort(ratesByCount{rates})
-
-		uptime := DayDuration{time.Since(hs.serverInfo.Started)}
-
-		status := statusData{
-			Version:   VERSION,
-			Zones:     rates,
-			Uptime:    uptime,
-			Platform:  runtime.GOARCH + "-" + runtime.GOOS,
-			TopOption: topOption,
-		}
-
-		status.Global.Queries = metrics.Get("queries").(*metrics.StandardMeter).Snapshot()
-
-		setupHistogramData(metrics.Get("queries-histogram").(*metrics.StandardHistogram).Snapshot(), &status.Global.Histogram)
-
-		statusTemplate, err := FSString(development, "/templates/status.html")
-		if err != nil {
-			log.Println("Could not read template:", err)
-			w.WriteHeader(500)
-			return
-		}
-		tmpl, err := template.New("status_html").Parse(statusTemplate)
-
-		if err != nil {
-			str := fmt.Sprintf("Could not parse template: %s", err)
-			io.WriteString(w, str)
-			return
-		}
-
-		err = tmpl.Execute(w, status)
-		if err != nil {
-			log.Println("Status template error", err)
-		}
-	}
-}
-
 func (hs *httpServer) mainServer(w http.ResponseWriter, req *http.Request) {
 	if req.RequestURI != "/version" {
 		http.NotFound(w, req)
@@ -240,13 +94,6 @@ type basicauth struct {
 
 func (b *basicauth) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 
-	// don't request passwords for the websocket interface (for now)
-	// because 'wscat' doesn't support that.
-	if r.RequestURI == "/monitor" {
-		b.h.ServeHTTP(w, r)
-		return
-	}
-
 	cfgMutex.RLock()
 	user := Config.HTTP.User
 	password := Config.HTTP.Password

http_test.go

@@ -9,7 +9,6 @@ import (
 
 	"github.com/stretchr/testify/require"
 
-	"github.com/abh/geodns/server"
 	"github.com/abh/geodns/targeting"
 	"github.com/abh/geodns/targeting/geoip2"
 	"github.com/abh/geodns/zones"
@@ -22,9 +21,6 @@ func TestHTTP(t *testing.T) {
 		targeting.Setup(geoprovider)
 	}
 
-	// todo: less global metrics ...
-	server.NewMetrics()
-
 	mm, err := zones.NewMuxManager("dns", &zones.NilReg{})
 	if err != nil {
 		t.Fatalf("loading zones: %s", err)
@@ -48,13 +44,4 @@ func TestHTTP(t *testing.T) {
 		t.Fail()
 	}
 
-	res, err = http.Get(baseurl + "/status")
-	require.Nil(t, err)
-	page, _ = ioutil.ReadAll(res.Body)
-
-	// just check that template basically works
-	if !bytes.Contains(page, []byte("<html>")) {
-		t.Log("/status didn't include <html>")
-		t.Fail()
-	}
 }

monitor/hub.go

@@ -1,99 +1 @@
 package monitor
-
-import (
-	"io"
-	"log"
-
-	"golang.org/x/net/websocket"
-)
-
-type monitorHub struct {
-	connections map[*wsConnection]bool
-	broadcast   chan string
-	register    chan *wsConnection
-	unregister  chan *wsConnection
-}
-
-var hub = monitorHub{
-	broadcast:   make(chan string),
-	register:    make(chan *wsConnection, 10),
-	unregister:  make(chan *wsConnection, 10),
-	connections: make(map[*wsConnection]bool),
-}
-
-type initialStatusFn func() string
-
-func (h *monitorHub) run(statusFn initialStatusFn) {
-	for {
-		select {
-		case c := <-h.register:
-			h.connections[c] = true
-			log.Println("Queuing initial status")
-			c.send <- statusFn()
-		case c := <-h.unregister:
-			log.Println("Unregistering connection")
-			delete(h.connections, c)
-		case m := <-h.broadcast:
-			for c := range h.connections {
-				if len(c.send)+5 > cap(c.send) {
-					log.Println("WS connection too close to cap")
-					c.send <- `{"error": "too slow"}`
-					close(c.send)
-					go c.ws.Close()
-					h.unregister <- c
-					continue
-				}
-				select {
-				case c.send <- m:
-				default:
-					close(c.send)
-					delete(h.connections, c)
-					log.Println("Closing channel when sending")
-					go c.ws.Close()
-				}
-			}
-		}
-	}
-}
-
-func (c *wsConnection) reader() {
-	for {
-		var message string
-		err := websocket.Message.Receive(c.ws, &message)
-		if err != nil {
-			if err == io.EOF {
-				log.Println("WS connection closed")
-			} else {
-				log.Println("WS read error:", err)
-			}
-			break
-		}
-		log.Println("WS message", message)
-		// TODO(ask) take configuration options etc
-		//h.broadcast <- message
-	}
-	c.ws.Close()
-}
-
-func (c *wsConnection) writer() {
-	for message := range c.send {
-		err := websocket.Message.Send(c.ws, message)
-		if err != nil {
-			log.Println("WS write error:", err)
-			break
-		}
-	}
-	c.ws.Close()
-}
-
-func wsHandler(ws *websocket.Conn) {
-	log.Println("Starting new WS connection")
-	c := &wsConnection{send: make(chan string, 180), ws: ws}
-	hub.register <- c
-	defer func() {
-		log.Println("sending unregister message")
-		hub.unregister <- c
-	}()
-	go c.writer()
-	c.reader()
-}

monitor/monitor.go

@@ -1,17 +1,12 @@
 package monitor
 
-//go:generate esc -o templates.go templates/
-
 import (
-	"encoding/json"
-	"os"
-	"runtime"
 	"time"
-
-	"github.com/rcrowley/go-metrics"
-	"golang.org/x/net/websocket"
 )
 
+// ServerInfo has the configured ID and groups and the first IP
+// address for the server among other 'who am I' information. The
+// UUID is reset on each restart.
 type ServerInfo struct {
 	Version string
 	ID      string
@@ -20,104 +15,3 @@ type ServerInfo struct {
 	Groups  []string
 	Started time.Time
 }
-
-// Initial status message on websocket
-type statusStreamMsgStart struct {
-	Hostname  string   `json:"h,omitemty"`
-	Version   string   `json:"v"`
-	GoVersion string   `json:"gov"`
-	ID        string   `json:"id"`
-	IP        string   `json:"ip"`
-	UUID      string   `json:"uuid"`
-	Uptime    int      `json:"up"`
-	Started   int      `json:"started"`
-	Groups    []string `json:"groups"`
-}
-
-// Update message on websocket
-type statusStreamMsgUpdate struct {
-	Uptime     int     `json:"up"`
-	QueryCount int64   `json:"qs"`
-	Qps        int64   `json:"qps"`
-	Qps1m      float64 `json:"qps1m,omitempty"`
-}
-
-type wsConnection struct {
-	// The websocket connection.
-	ws *websocket.Conn
-
-	// Buffered channel of outbound messages.
-	send chan string
-}
-
-type monitor struct {
-	serverInfo *ServerInfo
-}
-
-func NewMonitor(serverInfo *ServerInfo) *monitor {
-	return &monitor{serverInfo: serverInfo}
-}
-
-func (m *monitor) initialStatus() string {
-	status := new(statusStreamMsgStart)
-	status.Version = m.serverInfo.Version
-	status.ID = m.serverInfo.ID
-	status.IP = m.serverInfo.IP
-	status.UUID = m.serverInfo.UUID
-
-	status.GoVersion = runtime.Version()
-	if len(m.serverInfo.Groups) > 0 {
-		status.Groups = m.serverInfo.Groups
-	}
-	hostname, err := os.Hostname()
-	if err == nil {
-		status.Hostname = hostname
-	}
-
-	started := m.serverInfo.Started
-
-	status.Started = int(started.Unix())
-	status.Uptime = int(time.Since(started).Seconds())
-
-	message, err := json.Marshal(status)
-	return string(message)
-}
-
-func (m *monitor) Run() {
-	go hub.run(m.initialStatus)
-
-	qCounter := metrics.Get("queries").(metrics.Meter)
-	lastQueryCount := qCounter.Count()
-
-	status := new(statusStreamMsgUpdate)
-	var lastQps1m float64
-
-	for {
-		current := qCounter.Count()
-		newQueries := current - lastQueryCount
-		lastQueryCount = current
-
-		status.Uptime = int(time.Since(m.serverInfo.Started).Seconds())
-		status.QueryCount = qCounter.Count()
-		status.Qps = newQueries
-
-		newQps1m := qCounter.Rate1()
-		if newQps1m != lastQps1m {
-			status.Qps1m = newQps1m
-			lastQps1m = newQps1m
-		} else {
-			status.Qps1m = 0
-		}
-
-		message, err := json.Marshal(status)
-
-		if err == nil {
-			hub.broadcast <- string(message)
-		}
-		time.Sleep(1 * time.Second)
-	}
-}
-
-func (m *monitor) Handler() websocket.Handler {
-	return websocket.Handler(wsHandler)
-}

server/metrics.go

@@ -1,49 +0,0 @@
-package server
-
-import (
-	"runtime"
-	"time"
-
-	metrics "github.com/rcrowley/go-metrics"
-)
-
-type ServerMetrics struct {
-	qCounter         metrics.Meter
-	lastQueryCount   int64
-	queriesHistogram metrics.Histogram
-	goroutines       metrics.Gauge
-}
-
-func NewMetrics() *ServerMetrics {
-	m := new(ServerMetrics)
-
-	m.qCounter = metrics.GetOrRegisterMeter("queries", nil)
-	m.lastQueryCount = m.qCounter.Count()
-
-	m.queriesHistogram = metrics.GetOrRegisterHistogram(
-		"queries-histogram", nil,
-		metrics.NewExpDecaySample(600, 0.015),
-	)
-
-	m.goroutines = metrics.GetOrRegisterGauge("goroutines", nil)
-
-	return m
-}
-
-func (m *ServerMetrics) Updater() {
-
-	for {
-		time.Sleep(1 * time.Second)
-
-		// Make sure go-metrics get some input to update the rate
-		m.qCounter.Mark(0)
-
-		current := m.qCounter.Count()
-		newQueries := current - m.lastQueryCount
-		m.lastQueryCount = current
-
-		m.queriesHistogram.Update(newQueries)
-
-		m.goroutines.Update(int64(runtime.NumGoroutine()))
-	}
-}

server/serve.go

@@ -12,9 +12,9 @@ import (
 	"github.com/abh/geodns/applog"
 	"github.com/abh/geodns/querylog"
 	"github.com/abh/geodns/zones"
+	"github.com/prometheus/client_golang/prometheus"
 
 	"github.com/miekg/dns"
-	"github.com/rcrowley/go-metrics"
 )
 
 func getQuestionName(z *zones.Zone, fqdn string) string {
@@ -34,7 +34,7 @@ func (srv *Server) serve(w dns.ResponseWriter, req *dns.Msg, z *zones.Zone) {
 		qle = &querylog.Entry{
 			Time:   time.Now().UnixNano(),
 			Origin: z.Origin,
-			Name:   qnamefqdn,
+			Name:   strings.ToLower(qnamefqdn),
 			Qtype:  qtype,
 		}
 		defer srv.queryLogger.Write(qle)
@@ -43,12 +43,6 @@ func (srv *Server) serve(w dns.ResponseWriter, req *dns.Msg, z *zones.Zone) {
 	applog.Printf("[zone %s] incoming  %s %s (id %d) from %s\n", z.Origin, qnamefqdn,
 		dns.TypeToString[qtype], req.Id, w.RemoteAddr())
 
-	// Global meter
-	metrics.Get("queries").(metrics.Meter).Mark(1)
-
-	// Zone meter
-	z.Metrics.Queries.Mark(1)
-
 	applog.Println("Got request", req)
 
 	// qlabel is the qname without the zone origin suffix
@@ -86,7 +80,6 @@ func (srv *Server) serve(w dns.ResponseWriter, req *dns.Msg, z *zones.Zone) {
 				case *dns.EDNS0_NSID:
 					// do stuff with e.Nsid
 				case *dns.EDNS0_SUBNET:
-					z.Metrics.EdnsQueries.Mark(1)
 					applog.Println("Got edns", e.Address, e.Family, e.SourceNetmask, e.SourceScope)
 					if e.Address != nil {
 						edns = e
@@ -191,7 +184,7 @@ func (srv *Server) serve(w dns.ResponseWriter, req *dns.Msg, z *zones.Zone) {
 				if location != nil {
 					txt = append(txt, fmt.Sprintf("(%.3f,%.3f)", location.Latitude, location.Longitude))
 				} else {
-					txt = append(txt, "(?,?)")
+					txt = append(txt, "()")
 				}
 
 				m.Answer = []dns.RR{&dns.TXT{Hdr: h,
@@ -209,6 +202,13 @@ func (srv *Server) serve(w dns.ResponseWriter, req *dns.Msg, z *zones.Zone) {
 
 		// return NXDOMAIN
 		m.SetRcode(req, dns.RcodeNameError)
+		srv.metrics.Queries.With(
+			prometheus.Labels{
+				"zone":  z.Origin,
+				"qtype": dns.TypeToString[qtype],
+				"qname": "_error",
+				"rcode": dns.RcodeToString[m.Rcode],
+			}).Inc()
 		m.Authoritative = true
 
 		m.Ns = []dns.RR{z.SoaRR()}
@@ -253,6 +253,14 @@ func (srv *Server) serve(w dns.ResponseWriter, req *dns.Msg, z *zones.Zone) {
 		m.Ns = append(m.Ns, z.SoaRR())
 	}
 
+	srv.metrics.Queries.With(
+		prometheus.Labels{
+			"zone":  z.Origin,
+			"qtype": dns.TypeToString[qtype],
+			"qname": qlabel,
+			"rcode": dns.RcodeToString[m.Rcode],
+		}).Inc()
+
 	applog.Println(m)
 
 	if qle != nil {
@@ -279,10 +287,7 @@ func (srv *Server) statusRR(label string) []dns.RR {
 		status["h"] = hostname
 	}
 
-	qCounter := metrics.Get("queries").(metrics.Meter)
 	status["up"] = strconv.Itoa(int(time.Since(srv.info.Started).Seconds()))
-	status["qs"] = strconv.FormatInt(qCounter.Count(), 10)
-	status["qps1"] = fmt.Sprintf("%.4f", qCounter.Rate1())
 
 	js, err := json.Marshal(status)
 

server/serve_test.go

@@ -20,10 +20,6 @@ const (
 )
 
 func TestServe(t *testing.T) {
-	// setup and register global metrics for serve()
-	metrics := NewMetrics()
-	go metrics.Updater()
-
 	serverInfo := &monitor.ServerInfo{}
 
 	srv := NewServer(serverInfo)

server/server.go

@@ -8,24 +8,64 @@ import (
 	"github.com/abh/geodns/zones"
 
 	"github.com/miekg/dns"
+	"github.com/prometheus/client_golang/prometheus"
 )
 
+type serverMetrics struct {
+	Queries *prometheus.CounterVec
+}
+
 type Server struct {
 	queryLogger        querylog.QueryLogger
 	mux                *dns.ServeMux
 	PublicDebugQueries bool
 	info               *monitor.ServerInfo
+	metrics            *serverMetrics
 }
 
 func NewServer(si *monitor.ServerInfo) *Server {
 	mux := dns.NewServeMux()
 
-	// todo: this should be in the monitor package, or somewhere else.
-	// Also if we can stop the server later, need to stop the server too.
-	metrics := NewMetrics()
-	go metrics.Updater()
+	queries := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "dns_queries_total",
+			Help: "Number of served queries",
+		},
+		[]string{"zone", "qtype", "qname", "rcode"},
+	)
+	prometheus.MustRegister(queries)
+
+	buildInfo := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Name: "geodns_build_info",
+			Help: "GeoDNS build information (in labels)",
+		},
+		[]string{"Version", "ID", "IP", "Group"},
+	)
+	prometheus.MustRegister(buildInfo)
+
+	group := ""
+	if len(si.Groups) > 0 {
+		group = si.Groups[0]
+	}
+	buildInfo.WithLabelValues(si.Version, si.ID, si.IP, group).Set(1)
+
+	startTime := prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Name: "geodns_start_time_seconds",
+			Help: "Unix time process started",
+		},
+	)
+	prometheus.MustRegister(startTime)
+
+	nano := si.Started.UnixNano()
+	startTime.Set(float64(nano) / 1e9)
+
+	metrics := &serverMetrics{
+		Queries: queries,
+	}
 
-	return &Server{mux: mux, info: si}
+	return &Server{mux: mux, info: si, metrics: metrics}
 }
 
 // Setup the QueryLogger. For now it only supports writing to a file (and all

templates.go

@@ -1,222 +0,0 @@
-package main
-
-import (
-	"bytes"
-	"compress/gzip"
-	"encoding/base64"
-	"io/ioutil"
-	"net/http"
-	"os"
-	"path"
-	"sync"
-	"time"
-)
-
-type _escLocalFS struct{}
-
-var _escLocal _escLocalFS
-
-type _escStaticFS struct{}
-
-var _escStatic _escStaticFS
-
-type _escDirectory struct {
-	fs   http.FileSystem
-	name string
-}
-
-type _escFile struct {
-	compressed string
-	size       int64
-	modtime    int64
-	local      string
-	isDir      bool
-
-	once sync.Once
-	data []byte
-	name string
-}
-
-func (_escLocalFS) Open(name string) (http.File, error) {
-	f, present := _escData[path.Clean(name)]
-	if !present {
-		return nil, os.ErrNotExist
-	}
-	return os.Open(f.local)
-}
-
-func (_escStaticFS) prepare(name string) (*_escFile, error) {
-	f, present := _escData[path.Clean(name)]
-	if !present {
-		return nil, os.ErrNotExist
-	}
-	var err error
-	f.once.Do(func() {
-		f.name = path.Base(name)
-		if f.size == 0 {
-			return
-		}
-		var gr *gzip.Reader
-		b64 := base64.NewDecoder(base64.StdEncoding, bytes.NewBufferString(f.compressed))
-		gr, err = gzip.NewReader(b64)
-		if err != nil {
-			return
-		}
-		f.data, err = ioutil.ReadAll(gr)
-	})
-	if err != nil {
-		return nil, err
-	}
-	return f, nil
-}
-
-func (fs _escStaticFS) Open(name string) (http.File, error) {
-	f, err := fs.prepare(name)
-	if err != nil {
-		return nil, err
-	}
-	return f.File()
-}
-
-func (dir _escDirectory) Open(name string) (http.File, error) {
-	return dir.fs.Open(dir.name + name)
-}
-
-func (f *_escFile) File() (http.File, error) {
-	type httpFile struct {
-		*bytes.Reader
-		*_escFile
-	}
-	return &httpFile{
-		Reader:   bytes.NewReader(f.data),
-		_escFile: f,
-	}, nil
-}
-
-func (f *_escFile) Close() error {
-	return nil
-}
-
-func (f *_escFile) Readdir(count int) ([]os.FileInfo, error) {
-	return nil, nil
-}
-
-func (f *_escFile) Stat() (os.FileInfo, error) {
-	return f, nil
-}
-
-func (f *_escFile) Name() string {
-	return f.name
-}
-
-func (f *_escFile) Size() int64 {
-	return f.size
-}
-
-func (f *_escFile) Mode() os.FileMode {
-	return 0
-}
-
-func (f *_escFile) ModTime() time.Time {
-	return time.Unix(f.modtime, 0)
-}
-
-func (f *_escFile) IsDir() bool {
-	return f.isDir
-}
-
-func (f *_escFile) Sys() interface{} {
-	return f
-}
-
-// FS returns a http.Filesystem for the embedded assets. If useLocal is true,
-// the filesystem's contents are instead used.
-func FS(useLocal bool) http.FileSystem {
-	if useLocal {
-		return _escLocal
-	}
-	return _escStatic
-}
-
-// Dir returns a http.Filesystem for the embedded assets on a given prefix dir.
-// If useLocal is true, the filesystem's contents are instead used.
-func Dir(useLocal bool, name string) http.FileSystem {
-	if useLocal {
-		return _escDirectory{fs: _escLocal, name: name}
-	}
-	return _escDirectory{fs: _escStatic, name: name}
-}
-
-// FSByte returns the named file from the embedded assets. If useLocal is
-// true, the filesystem's contents are instead used.
-func FSByte(useLocal bool, name string) ([]byte, error) {
-	if useLocal {
-		f, err := _escLocal.Open(name)
-		if err != nil {
-			return nil, err
-		}
-		b, err := ioutil.ReadAll(f)
-		f.Close()
-		return b, err
-	}
-	f, err := _escStatic.prepare(name)
-	if err != nil {
-		return nil, err
-	}
-	return f.data, nil
-}
-
-// FSMustByte is the same as FSByte, but panics if name is not present.
-func FSMustByte(useLocal bool, name string) []byte {
-	b, err := FSByte(useLocal, name)
-	if err != nil {
-		panic(err)
-	}
-	return b
-}
-
-// FSString is the string version of FSByte.
-func FSString(useLocal bool, name string) (string, error) {
-	b, err := FSByte(useLocal, name)
-	return string(b), err
-}
-
-// FSMustString is the string version of FSMustByte.
-func FSMustString(useLocal bool, name string) string {
-	return string(FSMustByte(useLocal, name))
-}
-
-var _escData = map[string]*_escFile{
-
-	"/templates/status.html": {
-		local:   "templates/status.html",
-		size:    3181,
-		modtime: 1442049075,
-		compressed: `
-H4sIAAAJbogA/7RXTY/bNhA9W7+CEJpbl4rSGKhTWpdskB7qdFO3PfRGiWOLqES65HidreD/XpD6sCxr
-Ha+KXCzpkW/IN/M0lFmOZZGwHLhIGEosIPkI+v7TmlQVoX+CsVIrcjyyqB4MWCHV3yQ3sFmGUaQAheI0
-1RotGr7LhKKZLiM8SEQwd91A9Ib+QOMoszbqsLtMl6lUIGgpFc2sDYmBYhlafCrA5gAY3rqeBw4cs7xd
-CMy+AK5Oq11dxD8lwQwF/VcrULyE71FQlxYwpCIbrfDuAHKb4zuS6kL8RI4BixoaS7V4SoKACflIsoJb
-uwwzrZBLBSZ0A3mcfCx0ygsW5fFgptEHN2fWx+yOqx89OmPI0wLagfrB/96l2ggwIJrHTCsByoIIk2Dm
-eMZfZwxFy5Zqo0ktKmw2RCxytCxC0c1OYlJKdQ7NL6F4BFsBPyEsclsY7iX5vAcjYbBkVe2MVLgh4Sv6
-ZhMSWu+ONpPpbxwh9jZ8IWk+hRRPYjnxPV4t319dfb5tMX+WFvXW8HKQ19XVCnlk8frVAFhcAHQIrfiX
-c2CN4h4ev1b7xnP/fMUCIiSkS3Enja6kurUuPdJ5VW5kPWS4eE2m8RZTeVeJz+WEf3n5anWxyIVZz93K
-IiEfxzrT2//VmVpD9KzcuviPHcoSTpvyYmiN0nv+tEYj1fa07e4Vez7kQ8Fxo005DNriI8EuM9Bd8zj5
-SyvnXNfGJyXA75VhnrAI8/rO99s9wgmZN4jtTRrBnLfJ54d1g9Q1rCryHerdrzt0R/e7JaG/t0/Hoxs2
-XG2BEOqVEIe5BPbbSlMnQTJduIIv5+1oezqGLoefeAld/loHsbYkF51+1JsrQCMz+1yjv5kzn8CJp5DO
-+smI6A/u4+klyj8IZaeoH/JuFXOx3lTiaCac+zK9V2i99VruLzyFYu0+NZwb39cTejb1LqwqIjcd/Xis
-3+wLY547M/Gh7fAtbm1+Fm1wjjYh3jov+yiNmqZF+F2OHOhVBUq4eO1No7qQMJT93mO36m4C3Cq8Dn5F
-eT/et5IedHenvnlqm/WHMYv8v4zgvwAAAP//sJ1SyW0MAAA=
-`,
-	},
-
-	"/": {
-		isDir: true,
-		local: "/",
-	},
-
-	"/templates": {
-		isDir: true,
-		local: "/templates",
-	},
-}

templates/status.html

@@ -1,147 +0,0 @@
-<html><head><title>GeoDNS {{ .Version }}</title>
-<link href="//netdna.bootstrapcdn.com/twitter-bootstrap/2.3.1/css/bootstrap-combined.min.css" rel="stylesheet">
-<link href="//netdna.bootstrapcdn.com/bootswatch/2.3.1/cerulean/bootstrap.min.css" rel="stylesheet">
-<style>
-	td.zonename,td.header { font-weight: bold; }
-</style>
-<body>
-
-<div class="container">
-
-<h1>Global</h1>
-
-<div class="row">
-
-	<div class="span8">
-
-		<table class="table table-bordered table-condensed">
-			<tr>
-				<td class="info header">Global stats</td>
-				<td>1 min</td>
-				<td>5 min</td>
-				<td>15 min</td>
-				<td>Mean</td>
-			</tr>
-
-			<tr>
-				<td>Queries</td>
-				<td>{{printf "%.2f" .Global.Queries.Rate1}}</td>
-				<td>{{printf "%.2f" .Global.Queries.Rate5}}</td>
-				<td>{{printf "%.2f" .Global.Queries.Rate15}}</td>
-				<td>{{printf "%.2f" .Global.Queries.RateMean}}</td>
-			</tr>
-		</table>
-
-		<table class="table table-bordered table-condensed">
-			<tr>
-				<td class="info header">Histograms</td>
-				<td>Min</td>
-				<td>Mean</td>
-				<td>90%</td>
-				<td>99%</td>
-				<td>99.9%</td>
-				<td>Max</td>
-				<td>StdDev</td>
-			</tr>
-
-			<tr>
-				<td>Global queries</td>
-				<td>{{printf "%d"   .Global.Histogram.Min}}</td>
-				<td>{{printf "%.2f" .Global.Histogram.Mean}}</td>
-				<td>{{printf "%.2f" .Global.Histogram.Pct90 }}</td>
-				<td>{{printf "%.2f" .Global.Histogram.Pct99 }}</td>
-				<td>{{printf "%.2f" .Global.Histogram.Pct999 }}</td>
-				<td>{{printf "%d"   .Global.Histogram.Max}}</td>
-				<td>{{printf "%.2f" .Global.Histogram.StdDev }}</td>
-			</tr>
-
-		</table>
-
-	</div>
-
-	<div class="span4">
-
-		<table class="table table-bordered table-condensed">
-		<tr>
-			<td class="header">Uptime</td>
-			<td>{{.Uptime.DayString}}</td>
-		</tr>
-		<tr>
-			<td class="header">Platform</td>
-			<td>{{.Platform}}</td>
-		</tr>
-		</table>
-
-	</div>
-
-</div>
-
-<h1>Zones</h1>
-<table class="table table-bordered table-condensed">
-<tr>
-<th></th>
-<th>1 minute</th>
-<th>5 minutes</th>
-<th>15 minutes</th>
-<th>Mean QPS</th>
-</tr>
-
-{{ $topOption := .TopOption}}
-
-{{range  .Zones }}
-
-	<tr class="info">
-		<td colspan=5 class="zonename">{{.Name}}</td>
-	</tr>
-
-	<tr>
-		<td>Queries</td>
-		<td>{{printf "%.2f" .Metrics.Queries.Rate1}}</td>
-		<td>{{printf "%.2f" .Metrics.Queries.Rate5}}</td>
-		<td>{{printf "%.2f" .Metrics.Queries.Rate15}}</td>
-		<td>{{printf "%.2f" .Metrics.Queries.RateMean}}</td>
-	</tr>
-
-	<tr>
-		<td>EDNS Queries</td>
-		<td>{{printf "%.2f" .Metrics.EdnsQueries.Rate1}}</td>
-		<td>{{printf "%.2f" .Metrics.EdnsQueries.Rate5}}</td>
-		<td>{{printf "%.2f" .Metrics.EdnsQueries.Rate15}}</td>
-		<td>{{printf "%.2f" .Metrics.EdnsQueries.RateMean}}</td>
-	</tr>
-
-	{{ $counts := .Metrics.LabelStats.TopCounts $topOption }}
-
-	{{ if $counts }}
-		<tr class="info">
-			<td colspan=5>Labels</td>
-		</tr>
-		{{range $counts }}
-			<tr>
-				<td colspan=4>{{.Label}}</td><td>{{.Count}}</td>
-			</tr>
-		{{end}}
-	{{end}}
-
-	{{ $clients := .Metrics.ClientStats.TopCounts $topOption }}
-
-	{{ if $clients }}
-		<tr class="info">
-			<td colspan=5>Clients</td>
-		</tr>
-		{{range $clients }}
-			<tr>
-				<td colspan=4>{{.Label}}</td><td>{{.Count}}</td>
-			</tr>
-		{{end}}
-	{{end}}
-
-
-{{end}}
-
-</table>
-
-</div>
-
-</body>
-</html>

vendor/github.com/beorn7/perks/LICENSE

@@ -0,0 +1,20 @@
+Copyright (C) 2013 Blake Mizerany
+
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

vendor/github.com/beorn7/perks/quantile/stream.go

@@ -0,0 +1,316 @@
+// Package quantile computes approximate quantiles over an unbounded data
+// stream within low memory and CPU bounds.
+//
+// A small amount of accuracy is traded to achieve the above properties.
+//
+// Multiple streams can be merged before calling Query to generate a single set
+// of results. This is meaningful when the streams represent the same type of
+// data. See Merge and Samples.
+//
+// For more detailed information about the algorithm used, see:
+//
+// Effective Computation of Biased Quantiles over Data Streams
+//
+// http://www.cs.rutgers.edu/~muthu/bquant.pdf
+package quantile
+
+import (
+	"math"
+	"sort"
+)
+
+// Sample holds an observed value and meta information for compression. JSON
+// tags have been added for convenience.
+type Sample struct {
+	Value float64 `json:",string"`
+	Width float64 `json:",string"`
+	Delta float64 `json:",string"`
+}
+
+// Samples represents a slice of samples. It implements sort.Interface.
+type Samples []Sample
+
+func (a Samples) Len() int           { return len(a) }
+func (a Samples) Less(i, j int) bool { return a[i].Value < a[j].Value }
+func (a Samples) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
+
+type invariant func(s *stream, r float64) float64
+
+// NewLowBiased returns an initialized Stream for low-biased quantiles
+// (e.g. 0.01, 0.1, 0.5) where the needed quantiles are not known a priori, but
+// error guarantees can still be given even for the lower ranks of the data
+// distribution.
+//
+// The provided epsilon is a relative error, i.e. the true quantile of a value
+// returned by a query is guaranteed to be within (1±Epsilon)*Quantile.
+//
+// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error
+// properties.
+func NewLowBiased(epsilon float64) *Stream {
+	ƒ := func(s *stream, r float64) float64 {
+		return 2 * epsilon * r
+	}
+	return newStream(ƒ)
+}
+
+// NewHighBiased returns an initialized Stream for high-biased quantiles
+// (e.g. 0.01, 0.1, 0.5) where the needed quantiles are not known a priori, but
+// error guarantees can still be given even for the higher ranks of the data
+// distribution.
+//
+// The provided epsilon is a relative error, i.e. the true quantile of a value
+// returned by a query is guaranteed to be within 1-(1±Epsilon)*(1-Quantile).
+//
+// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error
+// properties.
+func NewHighBiased(epsilon float64) *Stream {
+	ƒ := func(s *stream, r float64) float64 {
+		return 2 * epsilon * (s.n - r)
+	}
+	return newStream(ƒ)
+}
+
+// NewTargeted returns an initialized Stream concerned with a particular set of
+// quantile values that are supplied a priori. Knowing these a priori reduces
+// space and computation time. The targets map maps the desired quantiles to
+// their absolute errors, i.e. the true quantile of a value returned by a query
+// is guaranteed to be within (Quantile±Epsilon).
+//
+// See http://www.cs.rutgers.edu/~muthu/bquant.pdf for time, space, and error properties.
+func NewTargeted(targetMap map[float64]float64) *Stream {
+	// Convert map to slice to avoid slow iterations on a map.
+	// ƒ is called on the hot path, so converting the map to a slice
+	// beforehand results in significant CPU savings.
+	targets := targetMapToSlice(targetMap)
+
+	ƒ := func(s *stream, r float64) float64 {
+		var m = math.MaxFloat64
+		var f float64
+		for _, t := range targets {
+			if t.quantile*s.n <= r {
+				f = (2 * t.epsilon * r) / t.quantile
+			} else {
+				f = (2 * t.epsilon * (s.n - r)) / (1 - t.quantile)
+			}
+			if f < m {
+				m = f
+			}
+		}
+		return m
+	}
+	return newStream(ƒ)
+}
+
+type target struct {
+	quantile float64
+	epsilon  float64
+}
+
+func targetMapToSlice(targetMap map[float64]float64) []target {
+	targets := make([]target, 0, len(targetMap))
+
+	for quantile, epsilon := range targetMap {
+		t := target{
+			quantile: quantile,
+			epsilon:  epsilon,
+		}
+		targets = append(targets, t)
+	}
+
+	return targets
+}
+
+// Stream computes quantiles for a stream of float64s. It is not thread-safe by
+// design. Take care when using across multiple goroutines.
+type Stream struct {
+	*stream
+	b      Samples
+	sorted bool
+}
+
+func newStream(ƒ invariant) *Stream {
+	x := &stream{ƒ: ƒ}
+	return &Stream{x, make(Samples, 0, 500), true}
+}
+
+// Insert inserts v into the stream.
+func (s *Stream) Insert(v float64) {
+	s.insert(Sample{Value: v, Width: 1})
+}
+
+func (s *Stream) insert(sample Sample) {
+	s.b = append(s.b, sample)
+	s.sorted = false
+	if len(s.b) == cap(s.b) {
+		s.flush()
+	}
+}
+
+// Query returns the computed qth percentiles value. If s was created with
+// NewTargeted, and q is not in the set of quantiles provided a priori, Query
+// will return an unspecified result.
+func (s *Stream) Query(q float64) float64 {
+	if !s.flushed() {
+		// Fast path when there hasn't been enough data for a flush;
+		// this also yields better accuracy for small sets of data.
+		l := len(s.b)
+		if l == 0 {
+			return 0
+		}
+		i := int(math.Ceil(float64(l) * q))
+		if i > 0 {
+			i -= 1
+		}
+		s.maybeSort()
+		return s.b[i].Value
+	}
+	s.flush()
+	return s.stream.query(q)
+}
+
+// Merge merges samples into the underlying streams samples. This is handy when
+// merging multiple streams from separate threads, database shards, etc.
+//
+// ATTENTION: This method is broken and does not yield correct results. The
+// underlying algorithm is not capable of merging streams correctly.
+func (s *Stream) Merge(samples Samples) {
+	sort.Sort(samples)
+	s.stream.merge(samples)
+}
+
+// Reset reinitializes and clears the list reusing the samples buffer memory.
+func (s *Stream) Reset() {
+	s.stream.reset()
+	s.b = s.b[:0]
+}
+
+// Samples returns stream samples held by s.
+func (s *Stream) Samples() Samples {
+	if !s.flushed() {
+		return s.b
+	}
+	s.flush()
+	return s.stream.samples()
+}
+
+// Count returns the total number of samples observed in the stream
+// since initialization.
+func (s *Stream) Count() int {
+	return len(s.b) + s.stream.count()
+}
+
+func (s *Stream) flush() {
+	s.maybeSort()
+	s.stream.merge(s.b)
+	s.b = s.b[:0]
+}
+
+func (s *Stream) maybeSort() {
+	if !s.sorted {
+		s.sorted = true
+		sort.Sort(s.b)
+	}
+}
+
+func (s *Stream) flushed() bool {
+	return len(s.stream.l) > 0
+}
+
+type stream struct {
+	n float64
+	l []Sample
+	ƒ invariant
+}
+
+func (s *stream) reset() {
+	s.l = s.l[:0]
+	s.n = 0
+}
+
+func (s *stream) insert(v float64) {
+	s.merge(Samples{{v, 1, 0}})
+}
+
+func (s *stream) merge(samples Samples) {
+	// TODO(beorn7): This tries to merge not only individual samples, but
+	// whole summaries. The paper doesn't mention merging summaries at
+	// all. Unittests show that the merging is inaccurate. Find out how to
+	// do merges properly.
+	var r float64
+	i := 0
+	for _, sample := range samples {
+		for ; i < len(s.l); i++ {
+			c := s.l[i]
+			if c.Value > sample.Value {
+				// Insert at position i.
+				s.l = append(s.l, Sample{})
+				copy(s.l[i+1:], s.l[i:])
+				s.l[i] = Sample{
+					sample.Value,
+					sample.Width,
+					math.Max(sample.Delta, math.Floor(s.ƒ(s, r))-1),
+					// TODO(beorn7): How to calculate delta correctly?
+				}
+				i++
+				goto inserted
+			}
+			r += c.Width
+		}
+		s.l = append(s.l, Sample{sample.Value, sample.Width, 0})
+		i++
+	inserted:
+		s.n += sample.Width
+		r += sample.Width
+	}
+	s.compress()
+}
+
+func (s *stream) count() int {
+	return int(s.n)
+}
+
+func (s *stream) query(q float64) float64 {
+	t := math.Ceil(q * s.n)
+	t += math.Ceil(s.ƒ(s, t) / 2)
+	p := s.l[0]
+	var r float64
+	for _, c := range s.l[1:] {
+		r += p.Width
+		if r+c.Width+c.Delta > t {
+			return p.Value
+		}
+		p = c
+	}
+	return p.Value
+}
+
+func (s *stream) compress() {
+	if len(s.l) < 2 {
+		return
+	}
+	x := s.l[len(s.l)-1]
+	xi := len(s.l) - 1
+	r := s.n - 1 - x.Width
+
+	for i := len(s.l) - 2; i >= 0; i-- {
+		c := s.l[i]
+		if c.Width+x.Width+x.Delta <= s.ƒ(s, r) {
+			x.Width += c.Width
+			s.l[xi] = x
+			// Remove element at i.
+			copy(s.l[i:], s.l[i+1:])
+			s.l = s.l[:len(s.l)-1]
+			xi -= 1
+		} else {
+			x = c
+			xi = i
+		}
+		r -= c.Width
+	}
+}
+
+func (s *stream) samples() Samples {
+	samples := make(Samples, len(s.l))
+	copy(samples, s.l)
+	return samples
+}

vendor/github.com/golang/protobuf/AUTHORS

@@ -0,0 +1,3 @@
+# This source code refers to The Go Authors for copyright purposes.
+# The master list of authors is in the main Go distribution,
+# visible at http://tip.golang.org/AUTHORS.

vendor/github.com/golang/protobuf/CONTRIBUTORS

@@ -0,0 +1,3 @@
+# This source code was written by the Go contributors.
+# The master list of contributors is in the main Go distribution,
+# visible at http://tip.golang.org/CONTRIBUTORS.

vendor/github.com/golang/protobuf/LICENSE

@@ -0,0 +1,31 @@
+Go support for Protocol Buffers - Google's data interchange format
+
+Copyright 2010 The Go Authors.  All rights reserved.
+https://github.com/golang/protobuf
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+

vendor/github.com/golang/protobuf/proto/clone.go

@@ -0,0 +1,229 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2011 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Protocol buffer deep copy and merge.
+// TODO: RawMessage.
+
+package proto
+
+import (
+	"log"
+	"reflect"
+	"strings"
+)
+
+// Clone returns a deep copy of a protocol buffer.
+func Clone(pb Message) Message {
+	in := reflect.ValueOf(pb)
+	if in.IsNil() {
+		return pb
+	}
+
+	out := reflect.New(in.Type().Elem())
+	// out is empty so a merge is a deep copy.
+	mergeStruct(out.Elem(), in.Elem())
+	return out.Interface().(Message)
+}
+
+// Merge merges src into dst.
+// Required and optional fields that are set in src will be set to that value in dst.
+// Elements of repeated fields will be appended.
+// Merge panics if src and dst are not the same type, or if dst is nil.
+func Merge(dst, src Message) {
+	in := reflect.ValueOf(src)
+	out := reflect.ValueOf(dst)
+	if out.IsNil() {
+		panic("proto: nil destination")
+	}
+	if in.Type() != out.Type() {
+		// Explicit test prior to mergeStruct so that mistyped nils will fail
+		panic("proto: type mismatch")
+	}
+	if in.IsNil() {
+		// Merging nil into non-nil is a quiet no-op
+		return
+	}
+	mergeStruct(out.Elem(), in.Elem())
+}
+
+func mergeStruct(out, in reflect.Value) {
+	sprop := GetProperties(in.Type())
+	for i := 0; i < in.NumField(); i++ {
+		f := in.Type().Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		mergeAny(out.Field(i), in.Field(i), false, sprop.Prop[i])
+	}
+
+	if emIn, ok := extendable(in.Addr().Interface()); ok {
+		emOut, _ := extendable(out.Addr().Interface())
+		mIn, muIn := emIn.extensionsRead()
+		if mIn != nil {
+			mOut := emOut.extensionsWrite()
+			muIn.Lock()
+			mergeExtension(mOut, mIn)
+			muIn.Unlock()
+		}
+	}
+
+	uf := in.FieldByName("XXX_unrecognized")
+	if !uf.IsValid() {
+		return
+	}
+	uin := uf.Bytes()
+	if len(uin) > 0 {
+		out.FieldByName("XXX_unrecognized").SetBytes(append([]byte(nil), uin...))
+	}
+}
+
+// mergeAny performs a merge between two values of the same type.
+// viaPtr indicates whether the values were indirected through a pointer (implying proto2).
+// prop is set if this is a struct field (it may be nil).
+func mergeAny(out, in reflect.Value, viaPtr bool, prop *Properties) {
+	if in.Type() == protoMessageType {
+		if !in.IsNil() {
+			if out.IsNil() {
+				out.Set(reflect.ValueOf(Clone(in.Interface().(Message))))
+			} else {
+				Merge(out.Interface().(Message), in.Interface().(Message))
+			}
+		}
+		return
+	}
+	switch in.Kind() {
+	case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Int32, reflect.Int64,
+		reflect.String, reflect.Uint32, reflect.Uint64:
+		if !viaPtr && isProto3Zero(in) {
+			return
+		}
+		out.Set(in)
+	case reflect.Interface:
+		// Probably a oneof field; copy non-nil values.
+		if in.IsNil() {
+			return
+		}
+		// Allocate destination if it is not set, or set to a different type.
+		// Otherwise we will merge as normal.
+		if out.IsNil() || out.Elem().Type() != in.Elem().Type() {
+			out.Set(reflect.New(in.Elem().Elem().Type())) // interface -> *T -> T -> new(T)
+		}
+		mergeAny(out.Elem(), in.Elem(), false, nil)
+	case reflect.Map:
+		if in.Len() == 0 {
+			return
+		}
+		if out.IsNil() {
+			out.Set(reflect.MakeMap(in.Type()))
+		}
+		// For maps with value types of *T or []byte we need to deep copy each value.
+		elemKind := in.Type().Elem().Kind()
+		for _, key := range in.MapKeys() {
+			var val reflect.Value
+			switch elemKind {
+			case reflect.Ptr:
+				val = reflect.New(in.Type().Elem().Elem())
+				mergeAny(val, in.MapIndex(key), false, nil)
+			case reflect.Slice:
+				val = in.MapIndex(key)
+				val = reflect.ValueOf(append([]byte{}, val.Bytes()...))
+			default:
+				val = in.MapIndex(key)
+			}
+			out.SetMapIndex(key, val)
+		}
+	case reflect.Ptr:
+		if in.IsNil() {
+			return
+		}
+		if out.IsNil() {
+			out.Set(reflect.New(in.Elem().Type()))
+		}
+		mergeAny(out.Elem(), in.Elem(), true, nil)
+	case reflect.Slice:
+		if in.IsNil() {
+			return
+		}
+		if in.Type().Elem().Kind() == reflect.Uint8 {
+			// []byte is a scalar bytes field, not a repeated field.
+
+			// Edge case: if this is in a proto3 message, a zero length
+			// bytes field is considered the zero value, and should not
+			// be merged.
+			if prop != nil && prop.proto3 && in.Len() == 0 {
+				return
+			}
+
+			// Make a deep copy.
+			// Append to []byte{} instead of []byte(nil) so that we never end up
+			// with a nil result.
+			out.SetBytes(append([]byte{}, in.Bytes()...))
+			return
+		}
+		n := in.Len()
+		if out.IsNil() {
+			out.Set(reflect.MakeSlice(in.Type(), 0, n))
+		}
+		switch in.Type().Elem().Kind() {
+		case reflect.Bool, reflect.Float32, reflect.Float64, reflect.Int32, reflect.Int64,
+			reflect.String, reflect.Uint32, reflect.Uint64:
+			out.Set(reflect.AppendSlice(out, in))
+		default:
+			for i := 0; i < n; i++ {
+				x := reflect.Indirect(reflect.New(in.Type().Elem()))
+				mergeAny(x, in.Index(i), false, nil)
+				out.Set(reflect.Append(out, x))
+			}
+		}
+	case reflect.Struct:
+		mergeStruct(out, in)
+	default:
+		// unknown type, so not a protocol buffer
+		log.Printf("proto: don't know how to copy %v", in)
+	}
+}
+
+func mergeExtension(out, in map[int32]Extension) {
+	for extNum, eIn := range in {
+		eOut := Extension{desc: eIn.desc}
+		if eIn.value != nil {
+			v := reflect.New(reflect.TypeOf(eIn.value)).Elem()
+			mergeAny(v, reflect.ValueOf(eIn.value), false, nil)
+			eOut.value = v.Interface()
+		}
+		if eIn.enc != nil {
+			eOut.enc = make([]byte, len(eIn.enc))
+			copy(eOut.enc, eIn.enc)
+		}
+
+		out[extNum] = eOut
+	}
+}

vendor/github.com/golang/protobuf/proto/decode.go

@@ -0,0 +1,970 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Routines for decoding protocol buffer data to construct in-memory representations.
+ */
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"reflect"
+)
+
+// errOverflow is returned when an integer is too large to be represented.
+var errOverflow = errors.New("proto: integer overflow")
+
+// ErrInternalBadWireType is returned by generated code when an incorrect
+// wire type is encountered. It does not get returned to user code.
+var ErrInternalBadWireType = errors.New("proto: internal error: bad wiretype for oneof")
+
+// The fundamental decoders that interpret bytes on the wire.
+// Those that take integer types all return uint64 and are
+// therefore of type valueDecoder.
+
+// DecodeVarint reads a varint-encoded integer from the slice.
+// It returns the integer and the number of bytes consumed, or
+// zero if there is not enough.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func DecodeVarint(buf []byte) (x uint64, n int) {
+	for shift := uint(0); shift < 64; shift += 7 {
+		if n >= len(buf) {
+			return 0, 0
+		}
+		b := uint64(buf[n])
+		n++
+		x |= (b & 0x7F) << shift
+		if (b & 0x80) == 0 {
+			return x, n
+		}
+	}
+
+	// The number is too large to represent in a 64-bit value.
+	return 0, 0
+}
+
+func (p *Buffer) decodeVarintSlow() (x uint64, err error) {
+	i := p.index
+	l := len(p.buf)
+
+	for shift := uint(0); shift < 64; shift += 7 {
+		if i >= l {
+			err = io.ErrUnexpectedEOF
+			return
+		}
+		b := p.buf[i]
+		i++
+		x |= (uint64(b) & 0x7F) << shift
+		if b < 0x80 {
+			p.index = i
+			return
+		}
+	}
+
+	// The number is too large to represent in a 64-bit value.
+	err = errOverflow
+	return
+}
+
+// DecodeVarint reads a varint-encoded integer from the Buffer.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func (p *Buffer) DecodeVarint() (x uint64, err error) {
+	i := p.index
+	buf := p.buf
+
+	if i >= len(buf) {
+		return 0, io.ErrUnexpectedEOF
+	} else if buf[i] < 0x80 {
+		p.index++
+		return uint64(buf[i]), nil
+	} else if len(buf)-i < 10 {
+		return p.decodeVarintSlow()
+	}
+
+	var b uint64
+	// we already checked the first byte
+	x = uint64(buf[i]) - 0x80
+	i++
+
+	b = uint64(buf[i])
+	i++
+	x += b << 7
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 7
+
+	b = uint64(buf[i])
+	i++
+	x += b << 14
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 14
+
+	b = uint64(buf[i])
+	i++
+	x += b << 21
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 21
+
+	b = uint64(buf[i])
+	i++
+	x += b << 28
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 28
+
+	b = uint64(buf[i])
+	i++
+	x += b << 35
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 35
+
+	b = uint64(buf[i])
+	i++
+	x += b << 42
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 42
+
+	b = uint64(buf[i])
+	i++
+	x += b << 49
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 49
+
+	b = uint64(buf[i])
+	i++
+	x += b << 56
+	if b&0x80 == 0 {
+		goto done
+	}
+	x -= 0x80 << 56
+
+	b = uint64(buf[i])
+	i++
+	x += b << 63
+	if b&0x80 == 0 {
+		goto done
+	}
+	// x -= 0x80 << 63 // Always zero.
+
+	return 0, errOverflow
+
+done:
+	p.index = i
+	return x, nil
+}
+
+// DecodeFixed64 reads a 64-bit integer from the Buffer.
+// This is the format for the
+// fixed64, sfixed64, and double protocol buffer types.
+func (p *Buffer) DecodeFixed64() (x uint64, err error) {
+	// x, err already 0
+	i := p.index + 8
+	if i < 0 || i > len(p.buf) {
+		err = io.ErrUnexpectedEOF
+		return
+	}
+	p.index = i
+
+	x = uint64(p.buf[i-8])
+	x |= uint64(p.buf[i-7]) << 8
+	x |= uint64(p.buf[i-6]) << 16
+	x |= uint64(p.buf[i-5]) << 24
+	x |= uint64(p.buf[i-4]) << 32
+	x |= uint64(p.buf[i-3]) << 40
+	x |= uint64(p.buf[i-2]) << 48
+	x |= uint64(p.buf[i-1]) << 56
+	return
+}
+
+// DecodeFixed32 reads a 32-bit integer from the Buffer.
+// This is the format for the
+// fixed32, sfixed32, and float protocol buffer types.
+func (p *Buffer) DecodeFixed32() (x uint64, err error) {
+	// x, err already 0
+	i := p.index + 4
+	if i < 0 || i > len(p.buf) {
+		err = io.ErrUnexpectedEOF
+		return
+	}
+	p.index = i
+
+	x = uint64(p.buf[i-4])
+	x |= uint64(p.buf[i-3]) << 8
+	x |= uint64(p.buf[i-2]) << 16
+	x |= uint64(p.buf[i-1]) << 24
+	return
+}
+
+// DecodeZigzag64 reads a zigzag-encoded 64-bit integer
+// from the Buffer.
+// This is the format used for the sint64 protocol buffer type.
+func (p *Buffer) DecodeZigzag64() (x uint64, err error) {
+	x, err = p.DecodeVarint()
+	if err != nil {
+		return
+	}
+	x = (x >> 1) ^ uint64((int64(x&1)<<63)>>63)
+	return
+}
+
+// DecodeZigzag32 reads a zigzag-encoded 32-bit integer
+// from  the Buffer.
+// This is the format used for the sint32 protocol buffer type.
+func (p *Buffer) DecodeZigzag32() (x uint64, err error) {
+	x, err = p.DecodeVarint()
+	if err != nil {
+		return
+	}
+	x = uint64((uint32(x) >> 1) ^ uint32((int32(x&1)<<31)>>31))
+	return
+}
+
+// These are not ValueDecoders: they produce an array of bytes or a string.
+// bytes, embedded messages
+
+// DecodeRawBytes reads a count-delimited byte buffer from the Buffer.
+// This is the format used for the bytes protocol buffer
+// type and for embedded messages.
+func (p *Buffer) DecodeRawBytes(alloc bool) (buf []byte, err error) {
+	n, err := p.DecodeVarint()
+	if err != nil {
+		return nil, err
+	}
+
+	nb := int(n)
+	if nb < 0 {
+		return nil, fmt.Errorf("proto: bad byte length %d", nb)
+	}
+	end := p.index + nb
+	if end < p.index || end > len(p.buf) {
+		return nil, io.ErrUnexpectedEOF
+	}
+
+	if !alloc {
+		// todo: check if can get more uses of alloc=false
+		buf = p.buf[p.index:end]
+		p.index += nb
+		return
+	}
+
+	buf = make([]byte, nb)
+	copy(buf, p.buf[p.index:])
+	p.index += nb
+	return
+}
+
+// DecodeStringBytes reads an encoded string from the Buffer.
+// This is the format used for the proto2 string type.
+func (p *Buffer) DecodeStringBytes() (s string, err error) {
+	buf, err := p.DecodeRawBytes(false)
+	if err != nil {
+		return
+	}
+	return string(buf), nil
+}
+
+// Skip the next item in the buffer. Its wire type is decoded and presented as an argument.
+// If the protocol buffer has extensions, and the field matches, add it as an extension.
+// Otherwise, if the XXX_unrecognized field exists, append the skipped data there.
+func (o *Buffer) skipAndSave(t reflect.Type, tag, wire int, base structPointer, unrecField field) error {
+	oi := o.index
+
+	err := o.skip(t, tag, wire)
+	if err != nil {
+		return err
+	}
+
+	if !unrecField.IsValid() {
+		return nil
+	}
+
+	ptr := structPointer_Bytes(base, unrecField)
+
+	// Add the skipped field to struct field
+	obuf := o.buf
+
+	o.buf = *ptr
+	o.EncodeVarint(uint64(tag<<3 | wire))
+	*ptr = append(o.buf, obuf[oi:o.index]...)
+
+	o.buf = obuf
+
+	return nil
+}
+
+// Skip the next item in the buffer. Its wire type is decoded and presented as an argument.
+func (o *Buffer) skip(t reflect.Type, tag, wire int) error {
+
+	var u uint64
+	var err error
+
+	switch wire {
+	case WireVarint:
+		_, err = o.DecodeVarint()
+	case WireFixed64:
+		_, err = o.DecodeFixed64()
+	case WireBytes:
+		_, err = o.DecodeRawBytes(false)
+	case WireFixed32:
+		_, err = o.DecodeFixed32()
+	case WireStartGroup:
+		for {
+			u, err = o.DecodeVarint()
+			if err != nil {
+				break
+			}
+			fwire := int(u & 0x7)
+			if fwire == WireEndGroup {
+				break
+			}
+			ftag := int(u >> 3)
+			err = o.skip(t, ftag, fwire)
+			if err != nil {
+				break
+			}
+		}
+	default:
+		err = fmt.Errorf("proto: can't skip unknown wire type %d for %s", wire, t)
+	}
+	return err
+}
+
+// Unmarshaler is the interface representing objects that can
+// unmarshal themselves.  The method should reset the receiver before
+// decoding starts.  The argument points to data that may be
+// overwritten, so implementations should not keep references to the
+// buffer.
+type Unmarshaler interface {
+	Unmarshal([]byte) error
+}
+
+// Unmarshal parses the protocol buffer representation in buf and places the
+// decoded result in pb.  If the struct underlying pb does not match
+// the data in buf, the results can be unpredictable.
+//
+// Unmarshal resets pb before starting to unmarshal, so any
+// existing data in pb is always removed. Use UnmarshalMerge
+// to preserve and append to existing data.
+func Unmarshal(buf []byte, pb Message) error {
+	pb.Reset()
+	return UnmarshalMerge(buf, pb)
+}
+
+// UnmarshalMerge parses the protocol buffer representation in buf and
+// writes the decoded result to pb.  If the struct underlying pb does not match
+// the data in buf, the results can be unpredictable.
+//
+// UnmarshalMerge merges into existing data in pb.
+// Most code should use Unmarshal instead.
+func UnmarshalMerge(buf []byte, pb Message) error {
+	// If the object can unmarshal itself, let it.
+	if u, ok := pb.(Unmarshaler); ok {
+		return u.Unmarshal(buf)
+	}
+	return NewBuffer(buf).Unmarshal(pb)
+}
+
+// DecodeMessage reads a count-delimited message from the Buffer.
+func (p *Buffer) DecodeMessage(pb Message) error {
+	enc, err := p.DecodeRawBytes(false)
+	if err != nil {
+		return err
+	}
+	return NewBuffer(enc).Unmarshal(pb)
+}
+
+// DecodeGroup reads a tag-delimited group from the Buffer.
+func (p *Buffer) DecodeGroup(pb Message) error {
+	typ, base, err := getbase(pb)
+	if err != nil {
+		return err
+	}
+	return p.unmarshalType(typ.Elem(), GetProperties(typ.Elem()), true, base)
+}
+
+// Unmarshal parses the protocol buffer representation in the
+// Buffer and places the decoded result in pb.  If the struct
+// underlying pb does not match the data in the buffer, the results can be
+// unpredictable.
+//
+// Unlike proto.Unmarshal, this does not reset pb before starting to unmarshal.
+func (p *Buffer) Unmarshal(pb Message) error {
+	// If the object can unmarshal itself, let it.
+	if u, ok := pb.(Unmarshaler); ok {
+		err := u.Unmarshal(p.buf[p.index:])
+		p.index = len(p.buf)
+		return err
+	}
+
+	typ, base, err := getbase(pb)
+	if err != nil {
+		return err
+	}
+
+	err = p.unmarshalType(typ.Elem(), GetProperties(typ.Elem()), false, base)
+
+	if collectStats {
+		stats.Decode++
+	}
+
+	return err
+}
+
+// unmarshalType does the work of unmarshaling a structure.
+func (o *Buffer) unmarshalType(st reflect.Type, prop *StructProperties, is_group bool, base structPointer) error {
+	var state errorState
+	required, reqFields := prop.reqCount, uint64(0)
+
+	var err error
+	for err == nil && o.index < len(o.buf) {
+		oi := o.index
+		var u uint64
+		u, err = o.DecodeVarint()
+		if err != nil {
+			break
+		}
+		wire := int(u & 0x7)
+		if wire == WireEndGroup {
+			if is_group {
+				if required > 0 {
+					// Not enough information to determine the exact field.
+					// (See below.)
+					return &RequiredNotSetError{"{Unknown}"}
+				}
+				return nil // input is satisfied
+			}
+			return fmt.Errorf("proto: %s: wiretype end group for non-group", st)
+		}
+		tag := int(u >> 3)
+		if tag <= 0 {
+			return fmt.Errorf("proto: %s: illegal tag %d (wire type %d)", st, tag, wire)
+		}
+		fieldnum, ok := prop.decoderTags.get(tag)
+		if !ok {
+			// Maybe it's an extension?
+			if prop.extendable {
+				if e, _ := extendable(structPointer_Interface(base, st)); isExtensionField(e, int32(tag)) {
+					if err = o.skip(st, tag, wire); err == nil {
+						extmap := e.extensionsWrite()
+						ext := extmap[int32(tag)] // may be missing
+						ext.enc = append(ext.enc, o.buf[oi:o.index]...)
+						extmap[int32(tag)] = ext
+					}
+					continue
+				}
+			}
+			// Maybe it's a oneof?
+			if prop.oneofUnmarshaler != nil {
+				m := structPointer_Interface(base, st).(Message)
+				// First return value indicates whether tag is a oneof field.
+				ok, err = prop.oneofUnmarshaler(m, tag, wire, o)
+				if err == ErrInternalBadWireType {
+					// Map the error to something more descriptive.
+					// Do the formatting here to save generated code space.
+					err = fmt.Errorf("bad wiretype for oneof field in %T", m)
+				}
+				if ok {
+					continue
+				}
+			}
+			err = o.skipAndSave(st, tag, wire, base, prop.unrecField)
+			continue
+		}
+		p := prop.Prop[fieldnum]
+
+		if p.dec == nil {
+			fmt.Fprintf(os.Stderr, "proto: no protobuf decoder for %s.%s\n", st, st.Field(fieldnum).Name)
+			continue
+		}
+		dec := p.dec
+		if wire != WireStartGroup && wire != p.WireType {
+			if wire == WireBytes && p.packedDec != nil {
+				// a packable field
+				dec = p.packedDec
+			} else {
+				err = fmt.Errorf("proto: bad wiretype for field %s.%s: got wiretype %d, want %d", st, st.Field(fieldnum).Name, wire, p.WireType)
+				continue
+			}
+		}
+		decErr := dec(o, p, base)
+		if decErr != nil && !state.shouldContinue(decErr, p) {
+			err = decErr
+		}
+		if err == nil && p.Required {
+			// Successfully decoded a required field.
+			if tag <= 64 {
+				// use bitmap for fields 1-64 to catch field reuse.
+				var mask uint64 = 1 << uint64(tag-1)
+				if reqFields&mask == 0 {
+					// new required field
+					reqFields |= mask
+					required--
+				}
+			} else {
+				// This is imprecise. It can be fooled by a required field
+				// with a tag > 64 that is encoded twice; that's very rare.
+				// A fully correct implementation would require allocating
+				// a data structure, which we would like to avoid.
+				required--
+			}
+		}
+	}
+	if err == nil {
+		if is_group {
+			return io.ErrUnexpectedEOF
+		}
+		if state.err != nil {
+			return state.err
+		}
+		if required > 0 {
+			// Not enough information to determine the exact field. If we use extra
+			// CPU, we could determine the field only if the missing required field
+			// has a tag <= 64 and we check reqFields.
+			return &RequiredNotSetError{"{Unknown}"}
+		}
+	}
+	return err
+}
+
+// Individual type decoders
+// For each,
+//	u is the decoded value,
+//	v is a pointer to the field (pointer) in the struct
+
+// Sizes of the pools to allocate inside the Buffer.
+// The goal is modest amortization and allocation
+// on at least 16-byte boundaries.
+const (
+	boolPoolSize   = 16
+	uint32PoolSize = 8
+	uint64PoolSize = 4
+)
+
+// Decode a bool.
+func (o *Buffer) dec_bool(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	if len(o.bools) == 0 {
+		o.bools = make([]bool, boolPoolSize)
+	}
+	o.bools[0] = u != 0
+	*structPointer_Bool(base, p.field) = &o.bools[0]
+	o.bools = o.bools[1:]
+	return nil
+}
+
+func (o *Buffer) dec_proto3_bool(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	*structPointer_BoolVal(base, p.field) = u != 0
+	return nil
+}
+
+// Decode an int32.
+func (o *Buffer) dec_int32(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	word32_Set(structPointer_Word32(base, p.field), o, uint32(u))
+	return nil
+}
+
+func (o *Buffer) dec_proto3_int32(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	word32Val_Set(structPointer_Word32Val(base, p.field), uint32(u))
+	return nil
+}
+
+// Decode an int64.
+func (o *Buffer) dec_int64(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	word64_Set(structPointer_Word64(base, p.field), o, u)
+	return nil
+}
+
+func (o *Buffer) dec_proto3_int64(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	word64Val_Set(structPointer_Word64Val(base, p.field), o, u)
+	return nil
+}
+
+// Decode a string.
+func (o *Buffer) dec_string(p *Properties, base structPointer) error {
+	s, err := o.DecodeStringBytes()
+	if err != nil {
+		return err
+	}
+	*structPointer_String(base, p.field) = &s
+	return nil
+}
+
+func (o *Buffer) dec_proto3_string(p *Properties, base structPointer) error {
+	s, err := o.DecodeStringBytes()
+	if err != nil {
+		return err
+	}
+	*structPointer_StringVal(base, p.field) = s
+	return nil
+}
+
+// Decode a slice of bytes ([]byte).
+func (o *Buffer) dec_slice_byte(p *Properties, base structPointer) error {
+	b, err := o.DecodeRawBytes(true)
+	if err != nil {
+		return err
+	}
+	*structPointer_Bytes(base, p.field) = b
+	return nil
+}
+
+// Decode a slice of bools ([]bool).
+func (o *Buffer) dec_slice_bool(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	v := structPointer_BoolSlice(base, p.field)
+	*v = append(*v, u != 0)
+	return nil
+}
+
+// Decode a slice of bools ([]bool) in packed format.
+func (o *Buffer) dec_slice_packed_bool(p *Properties, base structPointer) error {
+	v := structPointer_BoolSlice(base, p.field)
+
+	nn, err := o.DecodeVarint()
+	if err != nil {
+		return err
+	}
+	nb := int(nn) // number of bytes of encoded bools
+	fin := o.index + nb
+	if fin < o.index {
+		return errOverflow
+	}
+
+	y := *v
+	for o.index < fin {
+		u, err := p.valDec(o)
+		if err != nil {
+			return err
+		}
+		y = append(y, u != 0)
+	}
+
+	*v = y
+	return nil
+}
+
+// Decode a slice of int32s ([]int32).
+func (o *Buffer) dec_slice_int32(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+	structPointer_Word32Slice(base, p.field).Append(uint32(u))
+	return nil
+}
+
+// Decode a slice of int32s ([]int32) in packed format.
+func (o *Buffer) dec_slice_packed_int32(p *Properties, base structPointer) error {
+	v := structPointer_Word32Slice(base, p.field)
+
+	nn, err := o.DecodeVarint()
+	if err != nil {
+		return err
+	}
+	nb := int(nn) // number of bytes of encoded int32s
+
+	fin := o.index + nb
+	if fin < o.index {
+		return errOverflow
+	}
+	for o.index < fin {
+		u, err := p.valDec(o)
+		if err != nil {
+			return err
+		}
+		v.Append(uint32(u))
+	}
+	return nil
+}
+
+// Decode a slice of int64s ([]int64).
+func (o *Buffer) dec_slice_int64(p *Properties, base structPointer) error {
+	u, err := p.valDec(o)
+	if err != nil {
+		return err
+	}
+
+	structPointer_Word64Slice(base, p.field).Append(u)
+	return nil
+}
+
+// Decode a slice of int64s ([]int64) in packed format.
+func (o *Buffer) dec_slice_packed_int64(p *Properties, base structPointer) error {
+	v := structPointer_Word64Slice(base, p.field)
+
+	nn, err := o.DecodeVarint()
+	if err != nil {
+		return err
+	}
+	nb := int(nn) // number of bytes of encoded int64s
+
+	fin := o.index + nb
+	if fin < o.index {
+		return errOverflow
+	}
+	for o.index < fin {
+		u, err := p.valDec(o)
+		if err != nil {
+			return err
+		}
+		v.Append(u)
+	}
+	return nil
+}
+
+// Decode a slice of strings ([]string).
+func (o *Buffer) dec_slice_string(p *Properties, base structPointer) error {
+	s, err := o.DecodeStringBytes()
+	if err != nil {
+		return err
+	}
+	v := structPointer_StringSlice(base, p.field)
+	*v = append(*v, s)
+	return nil
+}
+
+// Decode a slice of slice of bytes ([][]byte).
+func (o *Buffer) dec_slice_slice_byte(p *Properties, base structPointer) error {
+	b, err := o.DecodeRawBytes(true)
+	if err != nil {
+		return err
+	}
+	v := structPointer_BytesSlice(base, p.field)
+	*v = append(*v, b)
+	return nil
+}
+
+// Decode a map field.
+func (o *Buffer) dec_new_map(p *Properties, base structPointer) error {
+	raw, err := o.DecodeRawBytes(false)
+	if err != nil {
+		return err
+	}
+	oi := o.index       // index at the end of this map entry
+	o.index -= len(raw) // move buffer back to start of map entry
+
+	mptr := structPointer_NewAt(base, p.field, p.mtype) // *map[K]V
+	if mptr.Elem().IsNil() {
+		mptr.Elem().Set(reflect.MakeMap(mptr.Type().Elem()))
+	}
+	v := mptr.Elem() // map[K]V
+
+	// Prepare addressable doubly-indirect placeholders for the key and value types.
+	// See enc_new_map for why.
+	keyptr := reflect.New(reflect.PtrTo(p.mtype.Key())).Elem() // addressable *K
+	keybase := toStructPointer(keyptr.Addr())                  // **K
+
+	var valbase structPointer
+	var valptr reflect.Value
+	switch p.mtype.Elem().Kind() {
+	case reflect.Slice:
+		// []byte
+		var dummy []byte
+		valptr = reflect.ValueOf(&dummy)  // *[]byte
+		valbase = toStructPointer(valptr) // *[]byte
+	case reflect.Ptr:
+		// message; valptr is **Msg; need to allocate the intermediate pointer
+		valptr = reflect.New(reflect.PtrTo(p.mtype.Elem())).Elem() // addressable *V
+		valptr.Set(reflect.New(valptr.Type().Elem()))
+		valbase = toStructPointer(valptr)
+	default:
+		// everything else
+		valptr = reflect.New(reflect.PtrTo(p.mtype.Elem())).Elem() // addressable *V
+		valbase = toStructPointer(valptr.Addr())                   // **V
+	}
+
+	// Decode.
+	// This parses a restricted wire format, namely the encoding of a message
+	// with two fields. See enc_new_map for the format.
+	for o.index < oi {
+		// tagcode for key and value properties are always a single byte
+		// because they have tags 1 and 2.
+		tagcode := o.buf[o.index]
+		o.index++
+		switch tagcode {
+		case p.mkeyprop.tagcode[0]:
+			if err := p.mkeyprop.dec(o, p.mkeyprop, keybase); err != nil {
+				return err
+			}
+		case p.mvalprop.tagcode[0]:
+			if err := p.mvalprop.dec(o, p.mvalprop, valbase); err != nil {
+				return err
+			}
+		default:
+			// TODO: Should we silently skip this instead?
+			return fmt.Errorf("proto: bad map data tag %d", raw[0])
+		}
+	}
+	keyelem, valelem := keyptr.Elem(), valptr.Elem()
+	if !keyelem.IsValid() {
+		keyelem = reflect.Zero(p.mtype.Key())
+	}
+	if !valelem.IsValid() {
+		valelem = reflect.Zero(p.mtype.Elem())
+	}
+
+	v.SetMapIndex(keyelem, valelem)
+	return nil
+}
+
+// Decode a group.
+func (o *Buffer) dec_struct_group(p *Properties, base structPointer) error {
+	bas := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(bas) {
+		// allocate new nested message
+		bas = toStructPointer(reflect.New(p.stype))
+		structPointer_SetStructPointer(base, p.field, bas)
+	}
+	return o.unmarshalType(p.stype, p.sprop, true, bas)
+}
+
+// Decode an embedded message.
+func (o *Buffer) dec_struct_message(p *Properties, base structPointer) (err error) {
+	raw, e := o.DecodeRawBytes(false)
+	if e != nil {
+		return e
+	}
+
+	bas := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(bas) {
+		// allocate new nested message
+		bas = toStructPointer(reflect.New(p.stype))
+		structPointer_SetStructPointer(base, p.field, bas)
+	}
+
+	// If the object can unmarshal itself, let it.
+	if p.isUnmarshaler {
+		iv := structPointer_Interface(bas, p.stype)
+		return iv.(Unmarshaler).Unmarshal(raw)
+	}
+
+	obuf := o.buf
+	oi := o.index
+	o.buf = raw
+	o.index = 0
+
+	err = o.unmarshalType(p.stype, p.sprop, false, bas)
+	o.buf = obuf
+	o.index = oi
+
+	return err
+}
+
+// Decode a slice of embedded messages.
+func (o *Buffer) dec_slice_struct_message(p *Properties, base structPointer) error {
+	return o.dec_slice_struct(p, false, base)
+}
+
+// Decode a slice of embedded groups.
+func (o *Buffer) dec_slice_struct_group(p *Properties, base structPointer) error {
+	return o.dec_slice_struct(p, true, base)
+}
+
+// Decode a slice of structs ([]*struct).
+func (o *Buffer) dec_slice_struct(p *Properties, is_group bool, base structPointer) error {
+	v := reflect.New(p.stype)
+	bas := toStructPointer(v)
+	structPointer_StructPointerSlice(base, p.field).Append(bas)
+
+	if is_group {
+		err := o.unmarshalType(p.stype, p.sprop, is_group, bas)
+		return err
+	}
+
+	raw, err := o.DecodeRawBytes(false)
+	if err != nil {
+		return err
+	}
+
+	// If the object can unmarshal itself, let it.
+	if p.isUnmarshaler {
+		iv := v.Interface()
+		return iv.(Unmarshaler).Unmarshal(raw)
+	}
+
+	obuf := o.buf
+	oi := o.index
+	o.buf = raw
+	o.index = 0
+
+	err = o.unmarshalType(p.stype, p.sprop, is_group, bas)
+
+	o.buf = obuf
+	o.index = oi
+
+	return err
+}

vendor/github.com/golang/protobuf/proto/discard.go

@@ -0,0 +1,151 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2017 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+)
+
+// DiscardUnknown recursively discards all unknown fields from this message
+// and all embedded messages.
+//
+// When unmarshaling a message with unrecognized fields, the tags and values
+// of such fields are preserved in the Message. This allows a later call to
+// marshal to be able to produce a message that continues to have those
+// unrecognized fields. To avoid this, DiscardUnknown is used to
+// explicitly clear the unknown fields after unmarshaling.
+//
+// For proto2 messages, the unknown fields of message extensions are only
+// discarded from messages that have been accessed via GetExtension.
+func DiscardUnknown(m Message) {
+	discardLegacy(m)
+}
+
+func discardLegacy(m Message) {
+	v := reflect.ValueOf(m)
+	if v.Kind() != reflect.Ptr || v.IsNil() {
+		return
+	}
+	v = v.Elem()
+	if v.Kind() != reflect.Struct {
+		return
+	}
+	t := v.Type()
+
+	for i := 0; i < v.NumField(); i++ {
+		f := t.Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		vf := v.Field(i)
+		tf := f.Type
+
+		// Unwrap tf to get its most basic type.
+		var isPointer, isSlice bool
+		if tf.Kind() == reflect.Slice && tf.Elem().Kind() != reflect.Uint8 {
+			isSlice = true
+			tf = tf.Elem()
+		}
+		if tf.Kind() == reflect.Ptr {
+			isPointer = true
+			tf = tf.Elem()
+		}
+		if isPointer && isSlice && tf.Kind() != reflect.Struct {
+			panic(fmt.Sprintf("%T.%s cannot be a slice of pointers to primitive types", m, f.Name))
+		}
+
+		switch tf.Kind() {
+		case reflect.Struct:
+			switch {
+			case !isPointer:
+				panic(fmt.Sprintf("%T.%s cannot be a direct struct value", m, f.Name))
+			case isSlice: // E.g., []*pb.T
+				for j := 0; j < vf.Len(); j++ {
+					discardLegacy(vf.Index(j).Interface().(Message))
+				}
+			default: // E.g., *pb.T
+				discardLegacy(vf.Interface().(Message))
+			}
+		case reflect.Map:
+			switch {
+			case isPointer || isSlice:
+				panic(fmt.Sprintf("%T.%s cannot be a pointer to a map or a slice of map values", m, f.Name))
+			default: // E.g., map[K]V
+				tv := vf.Type().Elem()
+				if tv.Kind() == reflect.Ptr && tv.Implements(protoMessageType) { // Proto struct (e.g., *T)
+					for _, key := range vf.MapKeys() {
+						val := vf.MapIndex(key)
+						discardLegacy(val.Interface().(Message))
+					}
+				}
+			}
+		case reflect.Interface:
+			// Must be oneof field.
+			switch {
+			case isPointer || isSlice:
+				panic(fmt.Sprintf("%T.%s cannot be a pointer to a interface or a slice of interface values", m, f.Name))
+			default: // E.g., test_proto.isCommunique_Union interface
+				if !vf.IsNil() && f.Tag.Get("protobuf_oneof") != "" {
+					vf = vf.Elem() // E.g., *test_proto.Communique_Msg
+					if !vf.IsNil() {
+						vf = vf.Elem()   // E.g., test_proto.Communique_Msg
+						vf = vf.Field(0) // E.g., Proto struct (e.g., *T) or primitive value
+						if vf.Kind() == reflect.Ptr {
+							discardLegacy(vf.Interface().(Message))
+						}
+					}
+				}
+			}
+		}
+	}
+
+	if vf := v.FieldByName("XXX_unrecognized"); vf.IsValid() {
+		if vf.Type() != reflect.TypeOf([]byte{}) {
+			panic("expected XXX_unrecognized to be of type []byte")
+		}
+		vf.Set(reflect.ValueOf([]byte(nil)))
+	}
+
+	// For proto2 messages, only discard unknown fields in message extensions
+	// that have been accessed via GetExtension.
+	if em, ok := extendable(m); ok {
+		// Ignore lock since discardLegacy is not concurrency safe.
+		emm, _ := em.extensionsRead()
+		for _, mx := range emm {
+			if m, ok := mx.value.(Message); ok {
+				discardLegacy(m)
+			}
+		}
+	}
+}

vendor/github.com/golang/protobuf/proto/encode.go

@@ -0,0 +1,1362 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Routines for encoding data into the wire format for protocol buffers.
+ */
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+	"sort"
+)
+
+// RequiredNotSetError is the error returned if Marshal is called with
+// a protocol buffer struct whose required fields have not
+// all been initialized. It is also the error returned if Unmarshal is
+// called with an encoded protocol buffer that does not include all the
+// required fields.
+//
+// When printed, RequiredNotSetError reports the first unset required field in a
+// message. If the field cannot be precisely determined, it is reported as
+// "{Unknown}".
+type RequiredNotSetError struct {
+	field string
+}
+
+func (e *RequiredNotSetError) Error() string {
+	return fmt.Sprintf("proto: required field %q not set", e.field)
+}
+
+var (
+	// errRepeatedHasNil is the error returned if Marshal is called with
+	// a struct with a repeated field containing a nil element.
+	errRepeatedHasNil = errors.New("proto: repeated field has nil element")
+
+	// errOneofHasNil is the error returned if Marshal is called with
+	// a struct with a oneof field containing a nil element.
+	errOneofHasNil = errors.New("proto: oneof field has nil value")
+
+	// ErrNil is the error returned if Marshal is called with nil.
+	ErrNil = errors.New("proto: Marshal called with nil")
+
+	// ErrTooLarge is the error returned if Marshal is called with a
+	// message that encodes to >2GB.
+	ErrTooLarge = errors.New("proto: message encodes to over 2 GB")
+)
+
+// The fundamental encoders that put bytes on the wire.
+// Those that take integer types all accept uint64 and are
+// therefore of type valueEncoder.
+
+const maxVarintBytes = 10 // maximum length of a varint
+
+// maxMarshalSize is the largest allowed size of an encoded protobuf,
+// since C++ and Java use signed int32s for the size.
+const maxMarshalSize = 1<<31 - 1
+
+// EncodeVarint returns the varint encoding of x.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+// Not used by the package itself, but helpful to clients
+// wishing to use the same encoding.
+func EncodeVarint(x uint64) []byte {
+	var buf [maxVarintBytes]byte
+	var n int
+	for n = 0; x > 127; n++ {
+		buf[n] = 0x80 | uint8(x&0x7F)
+		x >>= 7
+	}
+	buf[n] = uint8(x)
+	n++
+	return buf[0:n]
+}
+
+// EncodeVarint writes a varint-encoded integer to the Buffer.
+// This is the format for the
+// int32, int64, uint32, uint64, bool, and enum
+// protocol buffer types.
+func (p *Buffer) EncodeVarint(x uint64) error {
+	for x >= 1<<7 {
+		p.buf = append(p.buf, uint8(x&0x7f|0x80))
+		x >>= 7
+	}
+	p.buf = append(p.buf, uint8(x))
+	return nil
+}
+
+// SizeVarint returns the varint encoding size of an integer.
+func SizeVarint(x uint64) int {
+	return sizeVarint(x)
+}
+
+func sizeVarint(x uint64) (n int) {
+	for {
+		n++
+		x >>= 7
+		if x == 0 {
+			break
+		}
+	}
+	return n
+}
+
+// EncodeFixed64 writes a 64-bit integer to the Buffer.
+// This is the format for the
+// fixed64, sfixed64, and double protocol buffer types.
+func (p *Buffer) EncodeFixed64(x uint64) error {
+	p.buf = append(p.buf,
+		uint8(x),
+		uint8(x>>8),
+		uint8(x>>16),
+		uint8(x>>24),
+		uint8(x>>32),
+		uint8(x>>40),
+		uint8(x>>48),
+		uint8(x>>56))
+	return nil
+}
+
+func sizeFixed64(x uint64) int {
+	return 8
+}
+
+// EncodeFixed32 writes a 32-bit integer to the Buffer.
+// This is the format for the
+// fixed32, sfixed32, and float protocol buffer types.
+func (p *Buffer) EncodeFixed32(x uint64) error {
+	p.buf = append(p.buf,
+		uint8(x),
+		uint8(x>>8),
+		uint8(x>>16),
+		uint8(x>>24))
+	return nil
+}
+
+func sizeFixed32(x uint64) int {
+	return 4
+}
+
+// EncodeZigzag64 writes a zigzag-encoded 64-bit integer
+// to the Buffer.
+// This is the format used for the sint64 protocol buffer type.
+func (p *Buffer) EncodeZigzag64(x uint64) error {
+	// use signed number to get arithmetic right shift.
+	return p.EncodeVarint((x << 1) ^ uint64((int64(x) >> 63)))
+}
+
+func sizeZigzag64(x uint64) int {
+	return sizeVarint((x << 1) ^ uint64((int64(x) >> 63)))
+}
+
+// EncodeZigzag32 writes a zigzag-encoded 32-bit integer
+// to the Buffer.
+// This is the format used for the sint32 protocol buffer type.
+func (p *Buffer) EncodeZigzag32(x uint64) error {
+	// use signed number to get arithmetic right shift.
+	return p.EncodeVarint(uint64((uint32(x) << 1) ^ uint32((int32(x) >> 31))))
+}
+
+func sizeZigzag32(x uint64) int {
+	return sizeVarint(uint64((uint32(x) << 1) ^ uint32((int32(x) >> 31))))
+}
+
+// EncodeRawBytes writes a count-delimited byte buffer to the Buffer.
+// This is the format used for the bytes protocol buffer
+// type and for embedded messages.
+func (p *Buffer) EncodeRawBytes(b []byte) error {
+	p.EncodeVarint(uint64(len(b)))
+	p.buf = append(p.buf, b...)
+	return nil
+}
+
+func sizeRawBytes(b []byte) int {
+	return sizeVarint(uint64(len(b))) +
+		len(b)
+}
+
+// EncodeStringBytes writes an encoded string to the Buffer.
+// This is the format used for the proto2 string type.
+func (p *Buffer) EncodeStringBytes(s string) error {
+	p.EncodeVarint(uint64(len(s)))
+	p.buf = append(p.buf, s...)
+	return nil
+}
+
+func sizeStringBytes(s string) int {
+	return sizeVarint(uint64(len(s))) +
+		len(s)
+}
+
+// Marshaler is the interface representing objects that can marshal themselves.
+type Marshaler interface {
+	Marshal() ([]byte, error)
+}
+
+// Marshal takes the protocol buffer
+// and encodes it into the wire format, returning the data.
+func Marshal(pb Message) ([]byte, error) {
+	// Can the object marshal itself?
+	if m, ok := pb.(Marshaler); ok {
+		return m.Marshal()
+	}
+	p := NewBuffer(nil)
+	err := p.Marshal(pb)
+	if p.buf == nil && err == nil {
+		// Return a non-nil slice on success.
+		return []byte{}, nil
+	}
+	return p.buf, err
+}
+
+// EncodeMessage writes the protocol buffer to the Buffer,
+// prefixed by a varint-encoded length.
+func (p *Buffer) EncodeMessage(pb Message) error {
+	t, base, err := getbase(pb)
+	if structPointer_IsNil(base) {
+		return ErrNil
+	}
+	if err == nil {
+		var state errorState
+		err = p.enc_len_struct(GetProperties(t.Elem()), base, &state)
+	}
+	return err
+}
+
+// Marshal takes the protocol buffer
+// and encodes it into the wire format, writing the result to the
+// Buffer.
+func (p *Buffer) Marshal(pb Message) error {
+	// Can the object marshal itself?
+	if m, ok := pb.(Marshaler); ok {
+		data, err := m.Marshal()
+		p.buf = append(p.buf, data...)
+		return err
+	}
+
+	t, base, err := getbase(pb)
+	if structPointer_IsNil(base) {
+		return ErrNil
+	}
+	if err == nil {
+		err = p.enc_struct(GetProperties(t.Elem()), base)
+	}
+
+	if collectStats {
+		(stats).Encode++ // Parens are to work around a goimports bug.
+	}
+
+	if len(p.buf) > maxMarshalSize {
+		return ErrTooLarge
+	}
+	return err
+}
+
+// Size returns the encoded size of a protocol buffer.
+func Size(pb Message) (n int) {
+	// Can the object marshal itself?  If so, Size is slow.
+	// TODO: add Size to Marshaler, or add a Sizer interface.
+	if m, ok := pb.(Marshaler); ok {
+		b, _ := m.Marshal()
+		return len(b)
+	}
+
+	t, base, err := getbase(pb)
+	if structPointer_IsNil(base) {
+		return 0
+	}
+	if err == nil {
+		n = size_struct(GetProperties(t.Elem()), base)
+	}
+
+	if collectStats {
+		(stats).Size++ // Parens are to work around a goimports bug.
+	}
+
+	return
+}
+
+// Individual type encoders.
+
+// Encode a bool.
+func (o *Buffer) enc_bool(p *Properties, base structPointer) error {
+	v := *structPointer_Bool(base, p.field)
+	if v == nil {
+		return ErrNil
+	}
+	x := 0
+	if *v {
+		x = 1
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, uint64(x))
+	return nil
+}
+
+func (o *Buffer) enc_proto3_bool(p *Properties, base structPointer) error {
+	v := *structPointer_BoolVal(base, p.field)
+	if !v {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, 1)
+	return nil
+}
+
+func size_bool(p *Properties, base structPointer) int {
+	v := *structPointer_Bool(base, p.field)
+	if v == nil {
+		return 0
+	}
+	return len(p.tagcode) + 1 // each bool takes exactly one byte
+}
+
+func size_proto3_bool(p *Properties, base structPointer) int {
+	v := *structPointer_BoolVal(base, p.field)
+	if !v && !p.oneof {
+		return 0
+	}
+	return len(p.tagcode) + 1 // each bool takes exactly one byte
+}
+
+// Encode an int32.
+func (o *Buffer) enc_int32(p *Properties, base structPointer) error {
+	v := structPointer_Word32(base, p.field)
+	if word32_IsNil(v) {
+		return ErrNil
+	}
+	x := int32(word32_Get(v)) // permit sign extension to use full 64-bit range
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, uint64(x))
+	return nil
+}
+
+func (o *Buffer) enc_proto3_int32(p *Properties, base structPointer) error {
+	v := structPointer_Word32Val(base, p.field)
+	x := int32(word32Val_Get(v)) // permit sign extension to use full 64-bit range
+	if x == 0 {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, uint64(x))
+	return nil
+}
+
+func size_int32(p *Properties, base structPointer) (n int) {
+	v := structPointer_Word32(base, p.field)
+	if word32_IsNil(v) {
+		return 0
+	}
+	x := int32(word32_Get(v)) // permit sign extension to use full 64-bit range
+	n += len(p.tagcode)
+	n += p.valSize(uint64(x))
+	return
+}
+
+func size_proto3_int32(p *Properties, base structPointer) (n int) {
+	v := structPointer_Word32Val(base, p.field)
+	x := int32(word32Val_Get(v)) // permit sign extension to use full 64-bit range
+	if x == 0 && !p.oneof {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += p.valSize(uint64(x))
+	return
+}
+
+// Encode a uint32.
+// Exactly the same as int32, except for no sign extension.
+func (o *Buffer) enc_uint32(p *Properties, base structPointer) error {
+	v := structPointer_Word32(base, p.field)
+	if word32_IsNil(v) {
+		return ErrNil
+	}
+	x := word32_Get(v)
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, uint64(x))
+	return nil
+}
+
+func (o *Buffer) enc_proto3_uint32(p *Properties, base structPointer) error {
+	v := structPointer_Word32Val(base, p.field)
+	x := word32Val_Get(v)
+	if x == 0 {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, uint64(x))
+	return nil
+}
+
+func size_uint32(p *Properties, base structPointer) (n int) {
+	v := structPointer_Word32(base, p.field)
+	if word32_IsNil(v) {
+		return 0
+	}
+	x := word32_Get(v)
+	n += len(p.tagcode)
+	n += p.valSize(uint64(x))
+	return
+}
+
+func size_proto3_uint32(p *Properties, base structPointer) (n int) {
+	v := structPointer_Word32Val(base, p.field)
+	x := word32Val_Get(v)
+	if x == 0 && !p.oneof {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += p.valSize(uint64(x))
+	return
+}
+
+// Encode an int64.
+func (o *Buffer) enc_int64(p *Properties, base structPointer) error {
+	v := structPointer_Word64(base, p.field)
+	if word64_IsNil(v) {
+		return ErrNil
+	}
+	x := word64_Get(v)
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, x)
+	return nil
+}
+
+func (o *Buffer) enc_proto3_int64(p *Properties, base structPointer) error {
+	v := structPointer_Word64Val(base, p.field)
+	x := word64Val_Get(v)
+	if x == 0 {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	p.valEnc(o, x)
+	return nil
+}
+
+func size_int64(p *Properties, base structPointer) (n int) {
+	v := structPointer_Word64(base, p.field)
+	if word64_IsNil(v) {
+		return 0
+	}
+	x := word64_Get(v)
+	n += len(p.tagcode)
+	n += p.valSize(x)
+	return
+}
+
+func size_proto3_int64(p *Properties, base structPointer) (n int) {
+	v := structPointer_Word64Val(base, p.field)
+	x := word64Val_Get(v)
+	if x == 0 && !p.oneof {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += p.valSize(x)
+	return
+}
+
+// Encode a string.
+func (o *Buffer) enc_string(p *Properties, base structPointer) error {
+	v := *structPointer_String(base, p.field)
+	if v == nil {
+		return ErrNil
+	}
+	x := *v
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeStringBytes(x)
+	return nil
+}
+
+func (o *Buffer) enc_proto3_string(p *Properties, base structPointer) error {
+	v := *structPointer_StringVal(base, p.field)
+	if v == "" {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeStringBytes(v)
+	return nil
+}
+
+func size_string(p *Properties, base structPointer) (n int) {
+	v := *structPointer_String(base, p.field)
+	if v == nil {
+		return 0
+	}
+	x := *v
+	n += len(p.tagcode)
+	n += sizeStringBytes(x)
+	return
+}
+
+func size_proto3_string(p *Properties, base structPointer) (n int) {
+	v := *structPointer_StringVal(base, p.field)
+	if v == "" && !p.oneof {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += sizeStringBytes(v)
+	return
+}
+
+// All protocol buffer fields are nillable, but be careful.
+func isNil(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Interface, reflect.Map, reflect.Ptr, reflect.Slice:
+		return v.IsNil()
+	}
+	return false
+}
+
+// Encode a message struct.
+func (o *Buffer) enc_struct_message(p *Properties, base structPointer) error {
+	var state errorState
+	structp := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(structp) {
+		return ErrNil
+	}
+
+	// Can the object marshal itself?
+	if p.isMarshaler {
+		m := structPointer_Interface(structp, p.stype).(Marshaler)
+		data, err := m.Marshal()
+		if err != nil && !state.shouldContinue(err, nil) {
+			return err
+		}
+		o.buf = append(o.buf, p.tagcode...)
+		o.EncodeRawBytes(data)
+		return state.err
+	}
+
+	o.buf = append(o.buf, p.tagcode...)
+	return o.enc_len_struct(p.sprop, structp, &state)
+}
+
+func size_struct_message(p *Properties, base structPointer) int {
+	structp := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(structp) {
+		return 0
+	}
+
+	// Can the object marshal itself?
+	if p.isMarshaler {
+		m := structPointer_Interface(structp, p.stype).(Marshaler)
+		data, _ := m.Marshal()
+		n0 := len(p.tagcode)
+		n1 := sizeRawBytes(data)
+		return n0 + n1
+	}
+
+	n0 := len(p.tagcode)
+	n1 := size_struct(p.sprop, structp)
+	n2 := sizeVarint(uint64(n1)) // size of encoded length
+	return n0 + n1 + n2
+}
+
+// Encode a group struct.
+func (o *Buffer) enc_struct_group(p *Properties, base structPointer) error {
+	var state errorState
+	b := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(b) {
+		return ErrNil
+	}
+
+	o.EncodeVarint(uint64((p.Tag << 3) | WireStartGroup))
+	err := o.enc_struct(p.sprop, b)
+	if err != nil && !state.shouldContinue(err, nil) {
+		return err
+	}
+	o.EncodeVarint(uint64((p.Tag << 3) | WireEndGroup))
+	return state.err
+}
+
+func size_struct_group(p *Properties, base structPointer) (n int) {
+	b := structPointer_GetStructPointer(base, p.field)
+	if structPointer_IsNil(b) {
+		return 0
+	}
+
+	n += sizeVarint(uint64((p.Tag << 3) | WireStartGroup))
+	n += size_struct(p.sprop, b)
+	n += sizeVarint(uint64((p.Tag << 3) | WireEndGroup))
+	return
+}
+
+// Encode a slice of bools ([]bool).
+func (o *Buffer) enc_slice_bool(p *Properties, base structPointer) error {
+	s := *structPointer_BoolSlice(base, p.field)
+	l := len(s)
+	if l == 0 {
+		return ErrNil
+	}
+	for _, x := range s {
+		o.buf = append(o.buf, p.tagcode...)
+		v := uint64(0)
+		if x {
+			v = 1
+		}
+		p.valEnc(o, v)
+	}
+	return nil
+}
+
+func size_slice_bool(p *Properties, base structPointer) int {
+	s := *structPointer_BoolSlice(base, p.field)
+	l := len(s)
+	if l == 0 {
+		return 0
+	}
+	return l * (len(p.tagcode) + 1) // each bool takes exactly one byte
+}
+
+// Encode a slice of bools ([]bool) in packed format.
+func (o *Buffer) enc_slice_packed_bool(p *Properties, base structPointer) error {
+	s := *structPointer_BoolSlice(base, p.field)
+	l := len(s)
+	if l == 0 {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeVarint(uint64(l)) // each bool takes exactly one byte
+	for _, x := range s {
+		v := uint64(0)
+		if x {
+			v = 1
+		}
+		p.valEnc(o, v)
+	}
+	return nil
+}
+
+func size_slice_packed_bool(p *Properties, base structPointer) (n int) {
+	s := *structPointer_BoolSlice(base, p.field)
+	l := len(s)
+	if l == 0 {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += sizeVarint(uint64(l))
+	n += l // each bool takes exactly one byte
+	return
+}
+
+// Encode a slice of bytes ([]byte).
+func (o *Buffer) enc_slice_byte(p *Properties, base structPointer) error {
+	s := *structPointer_Bytes(base, p.field)
+	if s == nil {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeRawBytes(s)
+	return nil
+}
+
+func (o *Buffer) enc_proto3_slice_byte(p *Properties, base structPointer) error {
+	s := *structPointer_Bytes(base, p.field)
+	if len(s) == 0 {
+		return ErrNil
+	}
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeRawBytes(s)
+	return nil
+}
+
+func size_slice_byte(p *Properties, base structPointer) (n int) {
+	s := *structPointer_Bytes(base, p.field)
+	if s == nil && !p.oneof {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += sizeRawBytes(s)
+	return
+}
+
+func size_proto3_slice_byte(p *Properties, base structPointer) (n int) {
+	s := *structPointer_Bytes(base, p.field)
+	if len(s) == 0 && !p.oneof {
+		return 0
+	}
+	n += len(p.tagcode)
+	n += sizeRawBytes(s)
+	return
+}
+
+// Encode a slice of int32s ([]int32).
+func (o *Buffer) enc_slice_int32(p *Properties, base structPointer) error {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return ErrNil
+	}
+	for i := 0; i < l; i++ {
+		o.buf = append(o.buf, p.tagcode...)
+		x := int32(s.Index(i)) // permit sign extension to use full 64-bit range
+		p.valEnc(o, uint64(x))
+	}
+	return nil
+}
+
+func size_slice_int32(p *Properties, base structPointer) (n int) {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return 0
+	}
+	for i := 0; i < l; i++ {
+		n += len(p.tagcode)
+		x := int32(s.Index(i)) // permit sign extension to use full 64-bit range
+		n += p.valSize(uint64(x))
+	}
+	return
+}
+
+// Encode a slice of int32s ([]int32) in packed format.
+func (o *Buffer) enc_slice_packed_int32(p *Properties, base structPointer) error {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return ErrNil
+	}
+	// TODO: Reuse a Buffer.
+	buf := NewBuffer(nil)
+	for i := 0; i < l; i++ {
+		x := int32(s.Index(i)) // permit sign extension to use full 64-bit range
+		p.valEnc(buf, uint64(x))
+	}
+
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeVarint(uint64(len(buf.buf)))
+	o.buf = append(o.buf, buf.buf...)
+	return nil
+}
+
+func size_slice_packed_int32(p *Properties, base structPointer) (n int) {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return 0
+	}
+	var bufSize int
+	for i := 0; i < l; i++ {
+		x := int32(s.Index(i)) // permit sign extension to use full 64-bit range
+		bufSize += p.valSize(uint64(x))
+	}
+
+	n += len(p.tagcode)
+	n += sizeVarint(uint64(bufSize))
+	n += bufSize
+	return
+}
+
+// Encode a slice of uint32s ([]uint32).
+// Exactly the same as int32, except for no sign extension.
+func (o *Buffer) enc_slice_uint32(p *Properties, base structPointer) error {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return ErrNil
+	}
+	for i := 0; i < l; i++ {
+		o.buf = append(o.buf, p.tagcode...)
+		x := s.Index(i)
+		p.valEnc(o, uint64(x))
+	}
+	return nil
+}
+
+func size_slice_uint32(p *Properties, base structPointer) (n int) {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return 0
+	}
+	for i := 0; i < l; i++ {
+		n += len(p.tagcode)
+		x := s.Index(i)
+		n += p.valSize(uint64(x))
+	}
+	return
+}
+
+// Encode a slice of uint32s ([]uint32) in packed format.
+// Exactly the same as int32, except for no sign extension.
+func (o *Buffer) enc_slice_packed_uint32(p *Properties, base structPointer) error {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return ErrNil
+	}
+	// TODO: Reuse a Buffer.
+	buf := NewBuffer(nil)
+	for i := 0; i < l; i++ {
+		p.valEnc(buf, uint64(s.Index(i)))
+	}
+
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeVarint(uint64(len(buf.buf)))
+	o.buf = append(o.buf, buf.buf...)
+	return nil
+}
+
+func size_slice_packed_uint32(p *Properties, base structPointer) (n int) {
+	s := structPointer_Word32Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return 0
+	}
+	var bufSize int
+	for i := 0; i < l; i++ {
+		bufSize += p.valSize(uint64(s.Index(i)))
+	}
+
+	n += len(p.tagcode)
+	n += sizeVarint(uint64(bufSize))
+	n += bufSize
+	return
+}
+
+// Encode a slice of int64s ([]int64).
+func (o *Buffer) enc_slice_int64(p *Properties, base structPointer) error {
+	s := structPointer_Word64Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return ErrNil
+	}
+	for i := 0; i < l; i++ {
+		o.buf = append(o.buf, p.tagcode...)
+		p.valEnc(o, s.Index(i))
+	}
+	return nil
+}
+
+func size_slice_int64(p *Properties, base structPointer) (n int) {
+	s := structPointer_Word64Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return 0
+	}
+	for i := 0; i < l; i++ {
+		n += len(p.tagcode)
+		n += p.valSize(s.Index(i))
+	}
+	return
+}
+
+// Encode a slice of int64s ([]int64) in packed format.
+func (o *Buffer) enc_slice_packed_int64(p *Properties, base structPointer) error {
+	s := structPointer_Word64Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return ErrNil
+	}
+	// TODO: Reuse a Buffer.
+	buf := NewBuffer(nil)
+	for i := 0; i < l; i++ {
+		p.valEnc(buf, s.Index(i))
+	}
+
+	o.buf = append(o.buf, p.tagcode...)
+	o.EncodeVarint(uint64(len(buf.buf)))
+	o.buf = append(o.buf, buf.buf...)
+	return nil
+}
+
+func size_slice_packed_int64(p *Properties, base structPointer) (n int) {
+	s := structPointer_Word64Slice(base, p.field)
+	l := s.Len()
+	if l == 0 {
+		return 0
+	}
+	var bufSize int
+	for i := 0; i < l; i++ {
+		bufSize += p.valSize(s.Index(i))
+	}
+
+	n += len(p.tagcode)
+	n += sizeVarint(uint64(bufSize))
+	n += bufSize
+	return
+}
+
+// Encode a slice of slice of bytes ([][]byte).
+func (o *Buffer) enc_slice_slice_byte(p *Properties, base structPointer) error {
+	ss := *structPointer_BytesSlice(base, p.field)
+	l := len(ss)
+	if l == 0 {
+		return ErrNil
+	}
+	for i := 0; i < l; i++ {
+		o.buf = append(o.buf, p.tagcode...)
+		o.EncodeRawBytes(ss[i])
+	}
+	return nil
+}
+
+func size_slice_slice_byte(p *Properties, base structPointer) (n int) {
+	ss := *structPointer_BytesSlice(base, p.field)
+	l := len(ss)
+	if l == 0 {
+		return 0
+	}
+	n += l * len(p.tagcode)
+	for i := 0; i < l; i++ {
+		n += sizeRawBytes(ss[i])
+	}
+	return
+}
+
+// Encode a slice of strings ([]string).
+func (o *Buffer) enc_slice_string(p *Properties, base structPointer) error {
+	ss := *structPointer_StringSlice(base, p.field)
+	l := len(ss)
+	for i := 0; i < l; i++ {
+		o.buf = append(o.buf, p.tagcode...)
+		o.EncodeStringBytes(ss[i])
+	}
+	return nil
+}
+
+func size_slice_string(p *Properties, base structPointer) (n int) {
+	ss := *structPointer_StringSlice(base, p.field)
+	l := len(ss)
+	n += l * len(p.tagcode)
+	for i := 0; i < l; i++ {
+		n += sizeStringBytes(ss[i])
+	}
+	return
+}
+
+// Encode a slice of message structs ([]*struct).
+func (o *Buffer) enc_slice_struct_message(p *Properties, base structPointer) error {
+	var state errorState
+	s := structPointer_StructPointerSlice(base, p.field)
+	l := s.Len()
+
+	for i := 0; i < l; i++ {
+		structp := s.Index(i)
+		if structPointer_IsNil(structp) {
+			return errRepeatedHasNil
+		}
+
+		// Can the object marshal itself?
+		if p.isMarshaler {
+			m := structPointer_Interface(structp, p.stype).(Marshaler)
+			data, err := m.Marshal()
+			if err != nil && !state.shouldContinue(err, nil) {
+				return err
+			}
+			o.buf = append(o.buf, p.tagcode...)
+			o.EncodeRawBytes(data)
+			continue
+		}
+
+		o.buf = append(o.buf, p.tagcode...)
+		err := o.enc_len_struct(p.sprop, structp, &state)
+		if err != nil && !state.shouldContinue(err, nil) {
+			if err == ErrNil {
+				return errRepeatedHasNil
+			}
+			return err
+		}
+	}
+	return state.err
+}
+
+func size_slice_struct_message(p *Properties, base structPointer) (n int) {
+	s := structPointer_StructPointerSlice(base, p.field)
+	l := s.Len()
+	n += l * len(p.tagcode)
+	for i := 0; i < l; i++ {
+		structp := s.Index(i)
+		if structPointer_IsNil(structp) {
+			return // return the size up to this point
+		}
+
+		// Can the object marshal itself?
+		if p.isMarshaler {
+			m := structPointer_Interface(structp, p.stype).(Marshaler)
+			data, _ := m.Marshal()
+			n += sizeRawBytes(data)
+			continue
+		}
+
+		n0 := size_struct(p.sprop, structp)
+		n1 := sizeVarint(uint64(n0)) // size of encoded length
+		n += n0 + n1
+	}
+	return
+}
+
+// Encode a slice of group structs ([]*struct).
+func (o *Buffer) enc_slice_struct_group(p *Properties, base structPointer) error {
+	var state errorState
+	s := structPointer_StructPointerSlice(base, p.field)
+	l := s.Len()
+
+	for i := 0; i < l; i++ {
+		b := s.Index(i)
+		if structPointer_IsNil(b) {
+			return errRepeatedHasNil
+		}
+
+		o.EncodeVarint(uint64((p.Tag << 3) | WireStartGroup))
+
+		err := o.enc_struct(p.sprop, b)
+
+		if err != nil && !state.shouldContinue(err, nil) {
+			if err == ErrNil {
+				return errRepeatedHasNil
+			}
+			return err
+		}
+
+		o.EncodeVarint(uint64((p.Tag << 3) | WireEndGroup))
+	}
+	return state.err
+}
+
+func size_slice_struct_group(p *Properties, base structPointer) (n int) {
+	s := structPointer_StructPointerSlice(base, p.field)
+	l := s.Len()
+
+	n += l * sizeVarint(uint64((p.Tag<<3)|WireStartGroup))
+	n += l * sizeVarint(uint64((p.Tag<<3)|WireEndGroup))
+	for i := 0; i < l; i++ {
+		b := s.Index(i)
+		if structPointer_IsNil(b) {
+			return // return size up to this point
+		}
+
+		n += size_struct(p.sprop, b)
+	}
+	return
+}
+
+// Encode an extension map.
+func (o *Buffer) enc_map(p *Properties, base structPointer) error {
+	exts := structPointer_ExtMap(base, p.field)
+	if err := encodeExtensionsMap(*exts); err != nil {
+		return err
+	}
+
+	return o.enc_map_body(*exts)
+}
+
+func (o *Buffer) enc_exts(p *Properties, base structPointer) error {
+	exts := structPointer_Extensions(base, p.field)
+
+	v, mu := exts.extensionsRead()
+	if v == nil {
+		return nil
+	}
+
+	mu.Lock()
+	defer mu.Unlock()
+	if err := encodeExtensionsMap(v); err != nil {
+		return err
+	}
+
+	return o.enc_map_body(v)
+}
+
+func (o *Buffer) enc_map_body(v map[int32]Extension) error {
+	// Fast-path for common cases: zero or one extensions.
+	if len(v) <= 1 {
+		for _, e := range v {
+			o.buf = append(o.buf, e.enc...)
+		}
+		return nil
+	}
+
+	// Sort keys to provide a deterministic encoding.
+	keys := make([]int, 0, len(v))
+	for k := range v {
+		keys = append(keys, int(k))
+	}
+	sort.Ints(keys)
+
+	for _, k := range keys {
+		o.buf = append(o.buf, v[int32(k)].enc...)
+	}
+	return nil
+}
+
+func size_map(p *Properties, base structPointer) int {
+	v := structPointer_ExtMap(base, p.field)
+	return extensionsMapSize(*v)
+}
+
+func size_exts(p *Properties, base structPointer) int {
+	v := structPointer_Extensions(base, p.field)
+	return extensionsSize(v)
+}
+
+// Encode a map field.
+func (o *Buffer) enc_new_map(p *Properties, base structPointer) error {
+	var state errorState // XXX: or do we need to plumb this through?
+
+	/*
+		A map defined as
+			map<key_type, value_type> map_field = N;
+		is encoded in the same way as
+			message MapFieldEntry {
+				key_type key = 1;
+				value_type value = 2;
+			}
+			repeated MapFieldEntry map_field = N;
+	*/
+
+	v := structPointer_NewAt(base, p.field, p.mtype).Elem() // map[K]V
+	if v.Len() == 0 {
+		return nil
+	}
+
+	keycopy, valcopy, keybase, valbase := mapEncodeScratch(p.mtype)
+
+	enc := func() error {
+		if err := p.mkeyprop.enc(o, p.mkeyprop, keybase); err != nil {
+			return err
+		}
+		if err := p.mvalprop.enc(o, p.mvalprop, valbase); err != nil && err != ErrNil {
+			return err
+		}
+		return nil
+	}
+
+	// Don't sort map keys. It is not required by the spec, and C++ doesn't do it.
+	for _, key := range v.MapKeys() {
+		val := v.MapIndex(key)
+
+		keycopy.Set(key)
+		valcopy.Set(val)
+
+		o.buf = append(o.buf, p.tagcode...)
+		if err := o.enc_len_thing(enc, &state); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func size_new_map(p *Properties, base structPointer) int {
+	v := structPointer_NewAt(base, p.field, p.mtype).Elem() // map[K]V
+
+	keycopy, valcopy, keybase, valbase := mapEncodeScratch(p.mtype)
+
+	n := 0
+	for _, key := range v.MapKeys() {
+		val := v.MapIndex(key)
+		keycopy.Set(key)
+		valcopy.Set(val)
+
+		// Tag codes for key and val are the responsibility of the sub-sizer.
+		keysize := p.mkeyprop.size(p.mkeyprop, keybase)
+		valsize := p.mvalprop.size(p.mvalprop, valbase)
+		entry := keysize + valsize
+		// Add on tag code and length of map entry itself.
+		n += len(p.tagcode) + sizeVarint(uint64(entry)) + entry
+	}
+	return n
+}
+
+// mapEncodeScratch returns a new reflect.Value matching the map's value type,
+// and a structPointer suitable for passing to an encoder or sizer.
+func mapEncodeScratch(mapType reflect.Type) (keycopy, valcopy reflect.Value, keybase, valbase structPointer) {
+	// Prepare addressable doubly-indirect placeholders for the key and value types.
+	// This is needed because the element-type encoders expect **T, but the map iteration produces T.
+
+	keycopy = reflect.New(mapType.Key()).Elem()                 // addressable K
+	keyptr := reflect.New(reflect.PtrTo(keycopy.Type())).Elem() // addressable *K
+	keyptr.Set(keycopy.Addr())                                  //
+	keybase = toStructPointer(keyptr.Addr())                    // **K
+
+	// Value types are more varied and require special handling.
+	switch mapType.Elem().Kind() {
+	case reflect.Slice:
+		// []byte
+		var dummy []byte
+		valcopy = reflect.ValueOf(&dummy).Elem() // addressable []byte
+		valbase = toStructPointer(valcopy.Addr())
+	case reflect.Ptr:
+		// message; the generated field type is map[K]*Msg (so V is *Msg),
+		// so we only need one level of indirection.
+		valcopy = reflect.New(mapType.Elem()).Elem() // addressable V
+		valbase = toStructPointer(valcopy.Addr())
+	default:
+		// everything else
+		valcopy = reflect.New(mapType.Elem()).Elem()                // addressable V
+		valptr := reflect.New(reflect.PtrTo(valcopy.Type())).Elem() // addressable *V
+		valptr.Set(valcopy.Addr())                                  //
+		valbase = toStructPointer(valptr.Addr())                    // **V
+	}
+	return
+}
+
+// Encode a struct.
+func (o *Buffer) enc_struct(prop *StructProperties, base structPointer) error {
+	var state errorState
+	// Encode fields in tag order so that decoders may use optimizations
+	// that depend on the ordering.
+	// https://developers.google.com/protocol-buffers/docs/encoding#order
+	for _, i := range prop.order {
+		p := prop.Prop[i]
+		if p.enc != nil {
+			err := p.enc(o, p, base)
+			if err != nil {
+				if err == ErrNil {
+					if p.Required && state.err == nil {
+						state.err = &RequiredNotSetError{p.Name}
+					}
+				} else if err == errRepeatedHasNil {
+					// Give more context to nil values in repeated fields.
+					return errors.New("repeated field " + p.OrigName + " has nil element")
+				} else if !state.shouldContinue(err, p) {
+					return err
+				}
+			}
+			if len(o.buf) > maxMarshalSize {
+				return ErrTooLarge
+			}
+		}
+	}
+
+	// Do oneof fields.
+	if prop.oneofMarshaler != nil {
+		m := structPointer_Interface(base, prop.stype).(Message)
+		if err := prop.oneofMarshaler(m, o); err == ErrNil {
+			return errOneofHasNil
+		} else if err != nil {
+			return err
+		}
+	}
+
+	// Add unrecognized fields at the end.
+	if prop.unrecField.IsValid() {
+		v := *structPointer_Bytes(base, prop.unrecField)
+		if len(o.buf)+len(v) > maxMarshalSize {
+			return ErrTooLarge
+		}
+		if len(v) > 0 {
+			o.buf = append(o.buf, v...)
+		}
+	}
+
+	return state.err
+}
+
+func size_struct(prop *StructProperties, base structPointer) (n int) {
+	for _, i := range prop.order {
+		p := prop.Prop[i]
+		if p.size != nil {
+			n += p.size(p, base)
+		}
+	}
+
+	// Add unrecognized fields at the end.
+	if prop.unrecField.IsValid() {
+		v := *structPointer_Bytes(base, prop.unrecField)
+		n += len(v)
+	}
+
+	// Factor in any oneof fields.
+	if prop.oneofSizer != nil {
+		m := structPointer_Interface(base, prop.stype).(Message)
+		n += prop.oneofSizer(m)
+	}
+
+	return
+}
+
+var zeroes [20]byte // longer than any conceivable sizeVarint
+
+// Encode a struct, preceded by its encoded length (as a varint).
+func (o *Buffer) enc_len_struct(prop *StructProperties, base structPointer, state *errorState) error {
+	return o.enc_len_thing(func() error { return o.enc_struct(prop, base) }, state)
+}
+
+// Encode something, preceded by its encoded length (as a varint).
+func (o *Buffer) enc_len_thing(enc func() error, state *errorState) error {
+	iLen := len(o.buf)
+	o.buf = append(o.buf, 0, 0, 0, 0) // reserve four bytes for length
+	iMsg := len(o.buf)
+	err := enc()
+	if err != nil && !state.shouldContinue(err, nil) {
+		return err
+	}
+	lMsg := len(o.buf) - iMsg
+	lLen := sizeVarint(uint64(lMsg))
+	switch x := lLen - (iMsg - iLen); {
+	case x > 0: // actual length is x bytes larger than the space we reserved
+		// Move msg x bytes right.
+		o.buf = append(o.buf, zeroes[:x]...)
+		copy(o.buf[iMsg+x:], o.buf[iMsg:iMsg+lMsg])
+	case x < 0: // actual length is x bytes smaller than the space we reserved
+		// Move msg x bytes left.
+		copy(o.buf[iMsg+x:], o.buf[iMsg:iMsg+lMsg])
+		o.buf = o.buf[:len(o.buf)+x] // x is negative
+	}
+	// Encode the length in the reserved space.
+	o.buf = o.buf[:iLen]
+	o.EncodeVarint(uint64(lMsg))
+	o.buf = o.buf[:len(o.buf)+lMsg]
+	return state.err
+}
+
+// errorState maintains the first error that occurs and updates that error
+// with additional context.
+type errorState struct {
+	err error
+}
+
+// shouldContinue reports whether encoding should continue upon encountering the
+// given error. If the error is RequiredNotSetError, shouldContinue returns true
+// and, if this is the first appearance of that error, remembers it for future
+// reporting.
+//
+// If prop is not nil, it may update any error with additional context about the
+// field with the error.
+func (s *errorState) shouldContinue(err error, prop *Properties) bool {
+	// Ignore unset required fields.
+	reqNotSet, ok := err.(*RequiredNotSetError)
+	if !ok {
+		return false
+	}
+	if s.err == nil {
+		if prop != nil {
+			err = &RequiredNotSetError{prop.Name + "." + reqNotSet.field}
+		}
+		s.err = err
+	}
+	return true
+}

vendor/github.com/golang/protobuf/proto/equal.go

@@ -0,0 +1,300 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2011 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Protocol buffer comparison.
+
+package proto
+
+import (
+	"bytes"
+	"log"
+	"reflect"
+	"strings"
+)
+
+/*
+Equal returns true iff protocol buffers a and b are equal.
+The arguments must both be pointers to protocol buffer structs.
+
+Equality is defined in this way:
+  - Two messages are equal iff they are the same type,
+    corresponding fields are equal, unknown field sets
+    are equal, and extensions sets are equal.
+  - Two set scalar fields are equal iff their values are equal.
+    If the fields are of a floating-point type, remember that
+    NaN != x for all x, including NaN. If the message is defined
+    in a proto3 .proto file, fields are not "set"; specifically,
+    zero length proto3 "bytes" fields are equal (nil == {}).
+  - Two repeated fields are equal iff their lengths are the same,
+    and their corresponding elements are equal. Note a "bytes" field,
+    although represented by []byte, is not a repeated field and the
+    rule for the scalar fields described above applies.
+  - Two unset fields are equal.
+  - Two unknown field sets are equal if their current
+    encoded state is equal.
+  - Two extension sets are equal iff they have corresponding
+    elements that are pairwise equal.
+  - Two map fields are equal iff their lengths are the same,
+    and they contain the same set of elements. Zero-length map
+    fields are equal.
+  - Every other combination of things are not equal.
+
+The return value is undefined if a and b are not protocol buffers.
+*/
+func Equal(a, b Message) bool {
+	if a == nil || b == nil {
+		return a == b
+	}
+	v1, v2 := reflect.ValueOf(a), reflect.ValueOf(b)
+	if v1.Type() != v2.Type() {
+		return false
+	}
+	if v1.Kind() == reflect.Ptr {
+		if v1.IsNil() {
+			return v2.IsNil()
+		}
+		if v2.IsNil() {
+			return false
+		}
+		v1, v2 = v1.Elem(), v2.Elem()
+	}
+	if v1.Kind() != reflect.Struct {
+		return false
+	}
+	return equalStruct(v1, v2)
+}
+
+// v1 and v2 are known to have the same type.
+func equalStruct(v1, v2 reflect.Value) bool {
+	sprop := GetProperties(v1.Type())
+	for i := 0; i < v1.NumField(); i++ {
+		f := v1.Type().Field(i)
+		if strings.HasPrefix(f.Name, "XXX_") {
+			continue
+		}
+		f1, f2 := v1.Field(i), v2.Field(i)
+		if f.Type.Kind() == reflect.Ptr {
+			if n1, n2 := f1.IsNil(), f2.IsNil(); n1 && n2 {
+				// both unset
+				continue
+			} else if n1 != n2 {
+				// set/unset mismatch
+				return false
+			}
+			b1, ok := f1.Interface().(raw)
+			if ok {
+				b2 := f2.Interface().(raw)
+				// RawMessage
+				if !bytes.Equal(b1.Bytes(), b2.Bytes()) {
+					return false
+				}
+				continue
+			}
+			f1, f2 = f1.Elem(), f2.Elem()
+		}
+		if !equalAny(f1, f2, sprop.Prop[i]) {
+			return false
+		}
+	}
+
+	if em1 := v1.FieldByName("XXX_InternalExtensions"); em1.IsValid() {
+		em2 := v2.FieldByName("XXX_InternalExtensions")
+		if !equalExtensions(v1.Type(), em1.Interface().(XXX_InternalExtensions), em2.Interface().(XXX_InternalExtensions)) {
+			return false
+		}
+	}
+
+	if em1 := v1.FieldByName("XXX_extensions"); em1.IsValid() {
+		em2 := v2.FieldByName("XXX_extensions")
+		if !equalExtMap(v1.Type(), em1.Interface().(map[int32]Extension), em2.Interface().(map[int32]Extension)) {
+			return false
+		}
+	}
+
+	uf := v1.FieldByName("XXX_unrecognized")
+	if !uf.IsValid() {
+		return true
+	}
+
+	u1 := uf.Bytes()
+	u2 := v2.FieldByName("XXX_unrecognized").Bytes()
+	if !bytes.Equal(u1, u2) {
+		return false
+	}
+
+	return true
+}
+
+// v1 and v2 are known to have the same type.
+// prop may be nil.
+func equalAny(v1, v2 reflect.Value, prop *Properties) bool {
+	if v1.Type() == protoMessageType {
+		m1, _ := v1.Interface().(Message)
+		m2, _ := v2.Interface().(Message)
+		return Equal(m1, m2)
+	}
+	switch v1.Kind() {
+	case reflect.Bool:
+		return v1.Bool() == v2.Bool()
+	case reflect.Float32, reflect.Float64:
+		return v1.Float() == v2.Float()
+	case reflect.Int32, reflect.Int64:
+		return v1.Int() == v2.Int()
+	case reflect.Interface:
+		// Probably a oneof field; compare the inner values.
+		n1, n2 := v1.IsNil(), v2.IsNil()
+		if n1 || n2 {
+			return n1 == n2
+		}
+		e1, e2 := v1.Elem(), v2.Elem()
+		if e1.Type() != e2.Type() {
+			return false
+		}
+		return equalAny(e1, e2, nil)
+	case reflect.Map:
+		if v1.Len() != v2.Len() {
+			return false
+		}
+		for _, key := range v1.MapKeys() {
+			val2 := v2.MapIndex(key)
+			if !val2.IsValid() {
+				// This key was not found in the second map.
+				return false
+			}
+			if !equalAny(v1.MapIndex(key), val2, nil) {
+				return false
+			}
+		}
+		return true
+	case reflect.Ptr:
+		// Maps may have nil values in them, so check for nil.
+		if v1.IsNil() && v2.IsNil() {
+			return true
+		}
+		if v1.IsNil() != v2.IsNil() {
+			return false
+		}
+		return equalAny(v1.Elem(), v2.Elem(), prop)
+	case reflect.Slice:
+		if v1.Type().Elem().Kind() == reflect.Uint8 {
+			// short circuit: []byte
+
+			// Edge case: if this is in a proto3 message, a zero length
+			// bytes field is considered the zero value.
+			if prop != nil && prop.proto3 && v1.Len() == 0 && v2.Len() == 0 {
+				return true
+			}
+			if v1.IsNil() != v2.IsNil() {
+				return false
+			}
+			return bytes.Equal(v1.Interface().([]byte), v2.Interface().([]byte))
+		}
+
+		if v1.Len() != v2.Len() {
+			return false
+		}
+		for i := 0; i < v1.Len(); i++ {
+			if !equalAny(v1.Index(i), v2.Index(i), prop) {
+				return false
+			}
+		}
+		return true
+	case reflect.String:
+		return v1.Interface().(string) == v2.Interface().(string)
+	case reflect.Struct:
+		return equalStruct(v1, v2)
+	case reflect.Uint32, reflect.Uint64:
+		return v1.Uint() == v2.Uint()
+	}
+
+	// unknown type, so not a protocol buffer
+	log.Printf("proto: don't know how to compare %v", v1)
+	return false
+}
+
+// base is the struct type that the extensions are based on.
+// x1 and x2 are InternalExtensions.
+func equalExtensions(base reflect.Type, x1, x2 XXX_InternalExtensions) bool {
+	em1, _ := x1.extensionsRead()
+	em2, _ := x2.extensionsRead()
+	return equalExtMap(base, em1, em2)
+}
+
+func equalExtMap(base reflect.Type, em1, em2 map[int32]Extension) bool {
+	if len(em1) != len(em2) {
+		return false
+	}
+
+	for extNum, e1 := range em1 {
+		e2, ok := em2[extNum]
+		if !ok {
+			return false
+		}
+
+		m1, m2 := e1.value, e2.value
+
+		if m1 != nil && m2 != nil {
+			// Both are unencoded.
+			if !equalAny(reflect.ValueOf(m1), reflect.ValueOf(m2), nil) {
+				return false
+			}
+			continue
+		}
+
+		// At least one is encoded. To do a semantically correct comparison
+		// we need to unmarshal them first.
+		var desc *ExtensionDesc
+		if m := extensionMaps[base]; m != nil {
+			desc = m[extNum]
+		}
+		if desc == nil {
+			log.Printf("proto: don't know how to compare extension %d of %v", extNum, base)
+			continue
+		}
+		var err error
+		if m1 == nil {
+			m1, err = decodeExtension(e1.enc, desc)
+		}
+		if m2 == nil && err == nil {
+			m2, err = decodeExtension(e2.enc, desc)
+		}
+		if err != nil {
+			// The encoded form is invalid.
+			log.Printf("proto: badly encoded extension %d of %v: %v", extNum, base, err)
+			return false
+		}
+		if !equalAny(reflect.ValueOf(m1), reflect.ValueOf(m2), nil) {
+			return false
+		}
+	}
+
+	return true
+}

vendor/github.com/golang/protobuf/proto/extensions.go

@@ -0,0 +1,587 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Types and routines for supporting protocol buffer extensions.
+ */
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+	"strconv"
+	"sync"
+)
+
+// ErrMissingExtension is the error returned by GetExtension if the named extension is not in the message.
+var ErrMissingExtension = errors.New("proto: missing extension")
+
+// ExtensionRange represents a range of message extensions for a protocol buffer.
+// Used in code generated by the protocol compiler.
+type ExtensionRange struct {
+	Start, End int32 // both inclusive
+}
+
+// extendableProto is an interface implemented by any protocol buffer generated by the current
+// proto compiler that may be extended.
+type extendableProto interface {
+	Message
+	ExtensionRangeArray() []ExtensionRange
+	extensionsWrite() map[int32]Extension
+	extensionsRead() (map[int32]Extension, sync.Locker)
+}
+
+// extendableProtoV1 is an interface implemented by a protocol buffer generated by the previous
+// version of the proto compiler that may be extended.
+type extendableProtoV1 interface {
+	Message
+	ExtensionRangeArray() []ExtensionRange
+	ExtensionMap() map[int32]Extension
+}
+
+// extensionAdapter is a wrapper around extendableProtoV1 that implements extendableProto.
+type extensionAdapter struct {
+	extendableProtoV1
+}
+
+func (e extensionAdapter) extensionsWrite() map[int32]Extension {
+	return e.ExtensionMap()
+}
+
+func (e extensionAdapter) extensionsRead() (map[int32]Extension, sync.Locker) {
+	return e.ExtensionMap(), notLocker{}
+}
+
+// notLocker is a sync.Locker whose Lock and Unlock methods are nops.
+type notLocker struct{}
+
+func (n notLocker) Lock()   {}
+func (n notLocker) Unlock() {}
+
+// extendable returns the extendableProto interface for the given generated proto message.
+// If the proto message has the old extension format, it returns a wrapper that implements
+// the extendableProto interface.
+func extendable(p interface{}) (extendableProto, bool) {
+	if ep, ok := p.(extendableProto); ok {
+		return ep, ok
+	}
+	if ep, ok := p.(extendableProtoV1); ok {
+		return extensionAdapter{ep}, ok
+	}
+	return nil, false
+}
+
+// XXX_InternalExtensions is an internal representation of proto extensions.
+//
+// Each generated message struct type embeds an anonymous XXX_InternalExtensions field,
+// thus gaining the unexported 'extensions' method, which can be called only from the proto package.
+//
+// The methods of XXX_InternalExtensions are not concurrency safe in general,
+// but calls to logically read-only methods such as has and get may be executed concurrently.
+type XXX_InternalExtensions struct {
+	// The struct must be indirect so that if a user inadvertently copies a
+	// generated message and its embedded XXX_InternalExtensions, they
+	// avoid the mayhem of a copied mutex.
+	//
+	// The mutex serializes all logically read-only operations to p.extensionMap.
+	// It is up to the client to ensure that write operations to p.extensionMap are
+	// mutually exclusive with other accesses.
+	p *struct {
+		mu           sync.Mutex
+		extensionMap map[int32]Extension
+	}
+}
+
+// extensionsWrite returns the extension map, creating it on first use.
+func (e *XXX_InternalExtensions) extensionsWrite() map[int32]Extension {
+	if e.p == nil {
+		e.p = new(struct {
+			mu           sync.Mutex
+			extensionMap map[int32]Extension
+		})
+		e.p.extensionMap = make(map[int32]Extension)
+	}
+	return e.p.extensionMap
+}
+
+// extensionsRead returns the extensions map for read-only use.  It may be nil.
+// The caller must hold the returned mutex's lock when accessing Elements within the map.
+func (e *XXX_InternalExtensions) extensionsRead() (map[int32]Extension, sync.Locker) {
+	if e.p == nil {
+		return nil, nil
+	}
+	return e.p.extensionMap, &e.p.mu
+}
+
+var extendableProtoType = reflect.TypeOf((*extendableProto)(nil)).Elem()
+var extendableProtoV1Type = reflect.TypeOf((*extendableProtoV1)(nil)).Elem()
+
+// ExtensionDesc represents an extension specification.
+// Used in generated code from the protocol compiler.
+type ExtensionDesc struct {
+	ExtendedType  Message     // nil pointer to the type that is being extended
+	ExtensionType interface{} // nil pointer to the extension type
+	Field         int32       // field number
+	Name          string      // fully-qualified name of extension, for text formatting
+	Tag           string      // protobuf tag style
+	Filename      string      // name of the file in which the extension is defined
+}
+
+func (ed *ExtensionDesc) repeated() bool {
+	t := reflect.TypeOf(ed.ExtensionType)
+	return t.Kind() == reflect.Slice && t.Elem().Kind() != reflect.Uint8
+}
+
+// Extension represents an extension in a message.
+type Extension struct {
+	// When an extension is stored in a message using SetExtension
+	// only desc and value are set. When the message is marshaled
+	// enc will be set to the encoded form of the message.
+	//
+	// When a message is unmarshaled and contains extensions, each
+	// extension will have only enc set. When such an extension is
+	// accessed using GetExtension (or GetExtensions) desc and value
+	// will be set.
+	desc  *ExtensionDesc
+	value interface{}
+	enc   []byte
+}
+
+// SetRawExtension is for testing only.
+func SetRawExtension(base Message, id int32, b []byte) {
+	epb, ok := extendable(base)
+	if !ok {
+		return
+	}
+	extmap := epb.extensionsWrite()
+	extmap[id] = Extension{enc: b}
+}
+
+// isExtensionField returns true iff the given field number is in an extension range.
+func isExtensionField(pb extendableProto, field int32) bool {
+	for _, er := range pb.ExtensionRangeArray() {
+		if er.Start <= field && field <= er.End {
+			return true
+		}
+	}
+	return false
+}
+
+// checkExtensionTypes checks that the given extension is valid for pb.
+func checkExtensionTypes(pb extendableProto, extension *ExtensionDesc) error {
+	var pbi interface{} = pb
+	// Check the extended type.
+	if ea, ok := pbi.(extensionAdapter); ok {
+		pbi = ea.extendableProtoV1
+	}
+	if a, b := reflect.TypeOf(pbi), reflect.TypeOf(extension.ExtendedType); a != b {
+		return errors.New("proto: bad extended type; " + b.String() + " does not extend " + a.String())
+	}
+	// Check the range.
+	if !isExtensionField(pb, extension.Field) {
+		return errors.New("proto: bad extension number; not in declared ranges")
+	}
+	return nil
+}
+
+// extPropKey is sufficient to uniquely identify an extension.
+type extPropKey struct {
+	base  reflect.Type
+	field int32
+}
+
+var extProp = struct {
+	sync.RWMutex
+	m map[extPropKey]*Properties
+}{
+	m: make(map[extPropKey]*Properties),
+}
+
+func extensionProperties(ed *ExtensionDesc) *Properties {
+	key := extPropKey{base: reflect.TypeOf(ed.ExtendedType), field: ed.Field}
+
+	extProp.RLock()
+	if prop, ok := extProp.m[key]; ok {
+		extProp.RUnlock()
+		return prop
+	}
+	extProp.RUnlock()
+
+	extProp.Lock()
+	defer extProp.Unlock()
+	// Check again.
+	if prop, ok := extProp.m[key]; ok {
+		return prop
+	}
+
+	prop := new(Properties)
+	prop.Init(reflect.TypeOf(ed.ExtensionType), "unknown_name", ed.Tag, nil)
+	extProp.m[key] = prop
+	return prop
+}
+
+// encode encodes any unmarshaled (unencoded) extensions in e.
+func encodeExtensions(e *XXX_InternalExtensions) error {
+	m, mu := e.extensionsRead()
+	if m == nil {
+		return nil // fast path
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	return encodeExtensionsMap(m)
+}
+
+// encode encodes any unmarshaled (unencoded) extensions in e.
+func encodeExtensionsMap(m map[int32]Extension) error {
+	for k, e := range m {
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+
+		et := reflect.TypeOf(e.desc.ExtensionType)
+		props := extensionProperties(e.desc)
+
+		p := NewBuffer(nil)
+		// If e.value has type T, the encoder expects a *struct{ X T }.
+		// Pass a *T with a zero field and hope it all works out.
+		x := reflect.New(et)
+		x.Elem().Set(reflect.ValueOf(e.value))
+		if err := props.enc(p, props, toStructPointer(x)); err != nil {
+			return err
+		}
+		e.enc = p.buf
+		m[k] = e
+	}
+	return nil
+}
+
+func extensionsSize(e *XXX_InternalExtensions) (n int) {
+	m, mu := e.extensionsRead()
+	if m == nil {
+		return 0
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	return extensionsMapSize(m)
+}
+
+func extensionsMapSize(m map[int32]Extension) (n int) {
+	for _, e := range m {
+		if e.value == nil || e.desc == nil {
+			// Extension is only in its encoded form.
+			n += len(e.enc)
+			continue
+		}
+
+		// We don't skip extensions that have an encoded form set,
+		// because the extension value may have been mutated after
+		// the last time this function was called.
+
+		et := reflect.TypeOf(e.desc.ExtensionType)
+		props := extensionProperties(e.desc)
+
+		// If e.value has type T, the encoder expects a *struct{ X T }.
+		// Pass a *T with a zero field and hope it all works out.
+		x := reflect.New(et)
+		x.Elem().Set(reflect.ValueOf(e.value))
+		n += props.size(props, toStructPointer(x))
+	}
+	return
+}
+
+// HasExtension returns whether the given extension is present in pb.
+func HasExtension(pb Message, extension *ExtensionDesc) bool {
+	// TODO: Check types, field numbers, etc.?
+	epb, ok := extendable(pb)
+	if !ok {
+		return false
+	}
+	extmap, mu := epb.extensionsRead()
+	if extmap == nil {
+		return false
+	}
+	mu.Lock()
+	_, ok = extmap[extension.Field]
+	mu.Unlock()
+	return ok
+}
+
+// ClearExtension removes the given extension from pb.
+func ClearExtension(pb Message, extension *ExtensionDesc) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return
+	}
+	// TODO: Check types, field numbers, etc.?
+	extmap := epb.extensionsWrite()
+	delete(extmap, extension.Field)
+}
+
+// GetExtension parses and returns the given extension of pb.
+// If the extension is not present and has no default value it returns ErrMissingExtension.
+func GetExtension(pb Message, extension *ExtensionDesc) (interface{}, error) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return nil, errors.New("proto: not an extendable proto")
+	}
+
+	if err := checkExtensionTypes(epb, extension); err != nil {
+		return nil, err
+	}
+
+	emap, mu := epb.extensionsRead()
+	if emap == nil {
+		return defaultExtensionValue(extension)
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	e, ok := emap[extension.Field]
+	if !ok {
+		// defaultExtensionValue returns the default value or
+		// ErrMissingExtension if there is no default.
+		return defaultExtensionValue(extension)
+	}
+
+	if e.value != nil {
+		// Already decoded. Check the descriptor, though.
+		if e.desc != extension {
+			// This shouldn't happen. If it does, it means that
+			// GetExtension was called twice with two different
+			// descriptors with the same field number.
+			return nil, errors.New("proto: descriptor conflict")
+		}
+		return e.value, nil
+	}
+
+	v, err := decodeExtension(e.enc, extension)
+	if err != nil {
+		return nil, err
+	}
+
+	// Remember the decoded version and drop the encoded version.
+	// That way it is safe to mutate what we return.
+	e.value = v
+	e.desc = extension
+	e.enc = nil
+	emap[extension.Field] = e
+	return e.value, nil
+}
+
+// defaultExtensionValue returns the default value for extension.
+// If no default for an extension is defined ErrMissingExtension is returned.
+func defaultExtensionValue(extension *ExtensionDesc) (interface{}, error) {
+	t := reflect.TypeOf(extension.ExtensionType)
+	props := extensionProperties(extension)
+
+	sf, _, err := fieldDefault(t, props)
+	if err != nil {
+		return nil, err
+	}
+
+	if sf == nil || sf.value == nil {
+		// There is no default value.
+		return nil, ErrMissingExtension
+	}
+
+	if t.Kind() != reflect.Ptr {
+		// We do not need to return a Ptr, we can directly return sf.value.
+		return sf.value, nil
+	}
+
+	// We need to return an interface{} that is a pointer to sf.value.
+	value := reflect.New(t).Elem()
+	value.Set(reflect.New(value.Type().Elem()))
+	if sf.kind == reflect.Int32 {
+		// We may have an int32 or an enum, but the underlying data is int32.
+		// Since we can't set an int32 into a non int32 reflect.value directly
+		// set it as a int32.
+		value.Elem().SetInt(int64(sf.value.(int32)))
+	} else {
+		value.Elem().Set(reflect.ValueOf(sf.value))
+	}
+	return value.Interface(), nil
+}
+
+// decodeExtension decodes an extension encoded in b.
+func decodeExtension(b []byte, extension *ExtensionDesc) (interface{}, error) {
+	o := NewBuffer(b)
+
+	t := reflect.TypeOf(extension.ExtensionType)
+
+	props := extensionProperties(extension)
+
+	// t is a pointer to a struct, pointer to basic type or a slice.
+	// Allocate a "field" to store the pointer/slice itself; the
+	// pointer/slice will be stored here. We pass
+	// the address of this field to props.dec.
+	// This passes a zero field and a *t and lets props.dec
+	// interpret it as a *struct{ x t }.
+	value := reflect.New(t).Elem()
+
+	for {
+		// Discard wire type and field number varint. It isn't needed.
+		if _, err := o.DecodeVarint(); err != nil {
+			return nil, err
+		}
+
+		if err := props.dec(o, props, toStructPointer(value.Addr())); err != nil {
+			return nil, err
+		}
+
+		if o.index >= len(o.buf) {
+			break
+		}
+	}
+	return value.Interface(), nil
+}
+
+// GetExtensions returns a slice of the extensions present in pb that are also listed in es.
+// The returned slice has the same length as es; missing extensions will appear as nil elements.
+func GetExtensions(pb Message, es []*ExtensionDesc) (extensions []interface{}, err error) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return nil, errors.New("proto: not an extendable proto")
+	}
+	extensions = make([]interface{}, len(es))
+	for i, e := range es {
+		extensions[i], err = GetExtension(epb, e)
+		if err == ErrMissingExtension {
+			err = nil
+		}
+		if err != nil {
+			return
+		}
+	}
+	return
+}
+
+// ExtensionDescs returns a new slice containing pb's extension descriptors, in undefined order.
+// For non-registered extensions, ExtensionDescs returns an incomplete descriptor containing
+// just the Field field, which defines the extension's field number.
+func ExtensionDescs(pb Message) ([]*ExtensionDesc, error) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return nil, fmt.Errorf("proto: %T is not an extendable proto.Message", pb)
+	}
+	registeredExtensions := RegisteredExtensions(pb)
+
+	emap, mu := epb.extensionsRead()
+	if emap == nil {
+		return nil, nil
+	}
+	mu.Lock()
+	defer mu.Unlock()
+	extensions := make([]*ExtensionDesc, 0, len(emap))
+	for extid, e := range emap {
+		desc := e.desc
+		if desc == nil {
+			desc = registeredExtensions[extid]
+			if desc == nil {
+				desc = &ExtensionDesc{Field: extid}
+			}
+		}
+
+		extensions = append(extensions, desc)
+	}
+	return extensions, nil
+}
+
+// SetExtension sets the specified extension of pb to the specified value.
+func SetExtension(pb Message, extension *ExtensionDesc, value interface{}) error {
+	epb, ok := extendable(pb)
+	if !ok {
+		return errors.New("proto: not an extendable proto")
+	}
+	if err := checkExtensionTypes(epb, extension); err != nil {
+		return err
+	}
+	typ := reflect.TypeOf(extension.ExtensionType)
+	if typ != reflect.TypeOf(value) {
+		return errors.New("proto: bad extension value type")
+	}
+	// nil extension values need to be caught early, because the
+	// encoder can't distinguish an ErrNil due to a nil extension
+	// from an ErrNil due to a missing field. Extensions are
+	// always optional, so the encoder would just swallow the error
+	// and drop all the extensions from the encoded message.
+	if reflect.ValueOf(value).IsNil() {
+		return fmt.Errorf("proto: SetExtension called with nil value of type %T", value)
+	}
+
+	extmap := epb.extensionsWrite()
+	extmap[extension.Field] = Extension{desc: extension, value: value}
+	return nil
+}
+
+// ClearAllExtensions clears all extensions from pb.
+func ClearAllExtensions(pb Message) {
+	epb, ok := extendable(pb)
+	if !ok {
+		return
+	}
+	m := epb.extensionsWrite()
+	for k := range m {
+		delete(m, k)
+	}
+}
+
+// A global registry of extensions.
+// The generated code will register the generated descriptors by calling RegisterExtension.
+
+var extensionMaps = make(map[reflect.Type]map[int32]*ExtensionDesc)
+
+// RegisterExtension is called from the generated code.
+func RegisterExtension(desc *ExtensionDesc) {
+	st := reflect.TypeOf(desc.ExtendedType).Elem()
+	m := extensionMaps[st]
+	if m == nil {
+		m = make(map[int32]*ExtensionDesc)
+		extensionMaps[st] = m
+	}
+	if _, ok := m[desc.Field]; ok {
+		panic("proto: duplicate extension registered: " + st.String() + " " + strconv.Itoa(int(desc.Field)))
+	}
+	m[desc.Field] = desc
+}
+
+// RegisteredExtensions returns a map of the registered extensions of a
+// protocol buffer struct, indexed by the extension number.
+// The argument pb should be a nil pointer to the struct type.
+func RegisteredExtensions(pb Message) map[int32]*ExtensionDesc {
+	return extensionMaps[reflect.TypeOf(pb).Elem()]
+}

vendor/github.com/golang/protobuf/proto/lib.go

@@ -0,0 +1,897 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+/*
+Package proto converts data structures to and from the wire format of
+protocol buffers.  It works in concert with the Go source code generated
+for .proto files by the protocol compiler.
+
+A summary of the properties of the protocol buffer interface
+for a protocol buffer variable v:
+
+  - Names are turned from camel_case to CamelCase for export.
+  - There are no methods on v to set fields; just treat
+	them as structure fields.
+  - There are getters that return a field's value if set,
+	and return the field's default value if unset.
+	The getters work even if the receiver is a nil message.
+  - The zero value for a struct is its correct initialization state.
+	All desired fields must be set before marshaling.
+  - A Reset() method will restore a protobuf struct to its zero state.
+  - Non-repeated fields are pointers to the values; nil means unset.
+	That is, optional or required field int32 f becomes F *int32.
+  - Repeated fields are slices.
+  - Helper functions are available to aid the setting of fields.
+	msg.Foo = proto.String("hello") // set field
+  - Constants are defined to hold the default values of all fields that
+	have them.  They have the form Default_StructName_FieldName.
+	Because the getter methods handle defaulted values,
+	direct use of these constants should be rare.
+  - Enums are given type names and maps from names to values.
+	Enum values are prefixed by the enclosing message's name, or by the
+	enum's type name if it is a top-level enum. Enum types have a String
+	method, and a Enum method to assist in message construction.
+  - Nested messages, groups and enums have type names prefixed with the name of
+	the surrounding message type.
+  - Extensions are given descriptor names that start with E_,
+	followed by an underscore-delimited list of the nested messages
+	that contain it (if any) followed by the CamelCased name of the
+	extension field itself.  HasExtension, ClearExtension, GetExtension
+	and SetExtension are functions for manipulating extensions.
+  - Oneof field sets are given a single field in their message,
+	with distinguished wrapper types for each possible field value.
+  - Marshal and Unmarshal are functions to encode and decode the wire format.
+
+When the .proto file specifies `syntax="proto3"`, there are some differences:
+
+  - Non-repeated fields of non-message type are values instead of pointers.
+  - Enum types do not get an Enum method.
+
+The simplest way to describe this is to see an example.
+Given file test.proto, containing
+
+	package example;
+
+	enum FOO { X = 17; }
+
+	message Test {
+	  required string label = 1;
+	  optional int32 type = 2 [default=77];
+	  repeated int64 reps = 3;
+	  optional group OptionalGroup = 4 {
+	    required string RequiredField = 5;
+	  }
+	  oneof union {
+	    int32 number = 6;
+	    string name = 7;
+	  }
+	}
+
+The resulting file, test.pb.go, is:
+
+	package example
+
+	import proto "github.com/golang/protobuf/proto"
+	import math "math"
+
+	type FOO int32
+	const (
+		FOO_X FOO = 17
+	)
+	var FOO_name = map[int32]string{
+		17: "X",
+	}
+	var FOO_value = map[string]int32{
+		"X": 17,
+	}
+
+	func (x FOO) Enum() *FOO {
+		p := new(FOO)
+		*p = x
+		return p
+	}
+	func (x FOO) String() string {
+		return proto.EnumName(FOO_name, int32(x))
+	}
+	func (x *FOO) UnmarshalJSON(data []byte) error {
+		value, err := proto.UnmarshalJSONEnum(FOO_value, data)
+		if err != nil {
+			return err
+		}
+		*x = FOO(value)
+		return nil
+	}
+
+	type Test struct {
+		Label         *string             `protobuf:"bytes,1,req,name=label" json:"label,omitempty"`
+		Type          *int32              `protobuf:"varint,2,opt,name=type,def=77" json:"type,omitempty"`
+		Reps          []int64             `protobuf:"varint,3,rep,name=reps" json:"reps,omitempty"`
+		Optionalgroup *Test_OptionalGroup `protobuf:"group,4,opt,name=OptionalGroup" json:"optionalgroup,omitempty"`
+		// Types that are valid to be assigned to Union:
+		//	*Test_Number
+		//	*Test_Name
+		Union            isTest_Union `protobuf_oneof:"union"`
+		XXX_unrecognized []byte       `json:"-"`
+	}
+	func (m *Test) Reset()         { *m = Test{} }
+	func (m *Test) String() string { return proto.CompactTextString(m) }
+	func (*Test) ProtoMessage() {}
+
+	type isTest_Union interface {
+		isTest_Union()
+	}
+
+	type Test_Number struct {
+		Number int32 `protobuf:"varint,6,opt,name=number"`
+	}
+	type Test_Name struct {
+		Name string `protobuf:"bytes,7,opt,name=name"`
+	}
+
+	func (*Test_Number) isTest_Union() {}
+	func (*Test_Name) isTest_Union()   {}
+
+	func (m *Test) GetUnion() isTest_Union {
+		if m != nil {
+			return m.Union
+		}
+		return nil
+	}
+	const Default_Test_Type int32 = 77
+
+	func (m *Test) GetLabel() string {
+		if m != nil && m.Label != nil {
+			return *m.Label
+		}
+		return ""
+	}
+
+	func (m *Test) GetType() int32 {
+		if m != nil && m.Type != nil {
+			return *m.Type
+		}
+		return Default_Test_Type
+	}
+
+	func (m *Test) GetOptionalgroup() *Test_OptionalGroup {
+		if m != nil {
+			return m.Optionalgroup
+		}
+		return nil
+	}
+
+	type Test_OptionalGroup struct {
+		RequiredField *string `protobuf:"bytes,5,req" json:"RequiredField,omitempty"`
+	}
+	func (m *Test_OptionalGroup) Reset()         { *m = Test_OptionalGroup{} }
+	func (m *Test_OptionalGroup) String() string { return proto.CompactTextString(m) }
+
+	func (m *Test_OptionalGroup) GetRequiredField() string {
+		if m != nil && m.RequiredField != nil {
+			return *m.RequiredField
+		}
+		return ""
+	}
+
+	func (m *Test) GetNumber() int32 {
+		if x, ok := m.GetUnion().(*Test_Number); ok {
+			return x.Number
+		}
+		return 0
+	}
+
+	func (m *Test) GetName() string {
+		if x, ok := m.GetUnion().(*Test_Name); ok {
+			return x.Name
+		}
+		return ""
+	}
+
+	func init() {
+		proto.RegisterEnum("example.FOO", FOO_name, FOO_value)
+	}
+
+To create and play with a Test object:
+
+	package main
+
+	import (
+		"log"
+
+		"github.com/golang/protobuf/proto"
+		pb "./example.pb"
+	)
+
+	func main() {
+		test := &pb.Test{
+			Label: proto.String("hello"),
+			Type:  proto.Int32(17),
+			Reps:  []int64{1, 2, 3},
+			Optionalgroup: &pb.Test_OptionalGroup{
+				RequiredField: proto.String("good bye"),
+			},
+			Union: &pb.Test_Name{"fred"},
+		}
+		data, err := proto.Marshal(test)
+		if err != nil {
+			log.Fatal("marshaling error: ", err)
+		}
+		newTest := &pb.Test{}
+		err = proto.Unmarshal(data, newTest)
+		if err != nil {
+			log.Fatal("unmarshaling error: ", err)
+		}
+		// Now test and newTest contain the same data.
+		if test.GetLabel() != newTest.GetLabel() {
+			log.Fatalf("data mismatch %q != %q", test.GetLabel(), newTest.GetLabel())
+		}
+		// Use a type switch to determine which oneof was set.
+		switch u := test.Union.(type) {
+		case *pb.Test_Number: // u.Number contains the number.
+		case *pb.Test_Name: // u.Name contains the string.
+		}
+		// etc.
+	}
+*/
+package proto
+
+import (
+	"encoding/json"
+	"fmt"
+	"log"
+	"reflect"
+	"sort"
+	"strconv"
+	"sync"
+)
+
+// Message is implemented by generated protocol buffer messages.
+type Message interface {
+	Reset()
+	String() string
+	ProtoMessage()
+}
+
+// Stats records allocation details about the protocol buffer encoders
+// and decoders.  Useful for tuning the library itself.
+type Stats struct {
+	Emalloc uint64 // mallocs in encode
+	Dmalloc uint64 // mallocs in decode
+	Encode  uint64 // number of encodes
+	Decode  uint64 // number of decodes
+	Chit    uint64 // number of cache hits
+	Cmiss   uint64 // number of cache misses
+	Size    uint64 // number of sizes
+}
+
+// Set to true to enable stats collection.
+const collectStats = false
+
+var stats Stats
+
+// GetStats returns a copy of the global Stats structure.
+func GetStats() Stats { return stats }
+
+// A Buffer is a buffer manager for marshaling and unmarshaling
+// protocol buffers.  It may be reused between invocations to
+// reduce memory usage.  It is not necessary to use a Buffer;
+// the global functions Marshal and Unmarshal create a
+// temporary Buffer and are fine for most applications.
+type Buffer struct {
+	buf   []byte // encode/decode byte stream
+	index int    // read point
+
+	// pools of basic types to amortize allocation.
+	bools   []bool
+	uint32s []uint32
+	uint64s []uint64
+
+	// extra pools, only used with pointer_reflect.go
+	int32s   []int32
+	int64s   []int64
+	float32s []float32
+	float64s []float64
+}
+
+// NewBuffer allocates a new Buffer and initializes its internal data to
+// the contents of the argument slice.
+func NewBuffer(e []byte) *Buffer {
+	return &Buffer{buf: e}
+}
+
+// Reset resets the Buffer, ready for marshaling a new protocol buffer.
+func (p *Buffer) Reset() {
+	p.buf = p.buf[0:0] // for reading/writing
+	p.index = 0        // for reading
+}
+
+// SetBuf replaces the internal buffer with the slice,
+// ready for unmarshaling the contents of the slice.
+func (p *Buffer) SetBuf(s []byte) {
+	p.buf = s
+	p.index = 0
+}
+
+// Bytes returns the contents of the Buffer.
+func (p *Buffer) Bytes() []byte { return p.buf }
+
+/*
+ * Helper routines for simplifying the creation of optional fields of basic type.
+ */
+
+// Bool is a helper routine that allocates a new bool value
+// to store v and returns a pointer to it.
+func Bool(v bool) *bool {
+	return &v
+}
+
+// Int32 is a helper routine that allocates a new int32 value
+// to store v and returns a pointer to it.
+func Int32(v int32) *int32 {
+	return &v
+}
+
+// Int is a helper routine that allocates a new int32 value
+// to store v and returns a pointer to it, but unlike Int32
+// its argument value is an int.
+func Int(v int) *int32 {
+	p := new(int32)
+	*p = int32(v)
+	return p
+}
+
+// Int64 is a helper routine that allocates a new int64 value
+// to store v and returns a pointer to it.
+func Int64(v int64) *int64 {
+	return &v
+}
+
+// Float32 is a helper routine that allocates a new float32 value
+// to store v and returns a pointer to it.
+func Float32(v float32) *float32 {
+	return &v
+}
+
+// Float64 is a helper routine that allocates a new float64 value
+// to store v and returns a pointer to it.
+func Float64(v float64) *float64 {
+	return &v
+}
+
+// Uint32 is a helper routine that allocates a new uint32 value
+// to store v and returns a pointer to it.
+func Uint32(v uint32) *uint32 {
+	return &v
+}
+
+// Uint64 is a helper routine that allocates a new uint64 value
+// to store v and returns a pointer to it.
+func Uint64(v uint64) *uint64 {
+	return &v
+}
+
+// String is a helper routine that allocates a new string value
+// to store v and returns a pointer to it.
+func String(v string) *string {
+	return &v
+}
+
+// EnumName is a helper function to simplify printing protocol buffer enums
+// by name.  Given an enum map and a value, it returns a useful string.
+func EnumName(m map[int32]string, v int32) string {
+	s, ok := m[v]
+	if ok {
+		return s
+	}
+	return strconv.Itoa(int(v))
+}
+
+// UnmarshalJSONEnum is a helper function to simplify recovering enum int values
+// from their JSON-encoded representation. Given a map from the enum's symbolic
+// names to its int values, and a byte buffer containing the JSON-encoded
+// value, it returns an int32 that can be cast to the enum type by the caller.
+//
+// The function can deal with both JSON representations, numeric and symbolic.
+func UnmarshalJSONEnum(m map[string]int32, data []byte, enumName string) (int32, error) {
+	if data[0] == '"' {
+		// New style: enums are strings.
+		var repr string
+		if err := json.Unmarshal(data, &repr); err != nil {
+			return -1, err
+		}
+		val, ok := m[repr]
+		if !ok {
+			return 0, fmt.Errorf("unrecognized enum %s value %q", enumName, repr)
+		}
+		return val, nil
+	}
+	// Old style: enums are ints.
+	var val int32
+	if err := json.Unmarshal(data, &val); err != nil {
+		return 0, fmt.Errorf("cannot unmarshal %#q into enum %s", data, enumName)
+	}
+	return val, nil
+}
+
+// DebugPrint dumps the encoded data in b in a debugging format with a header
+// including the string s. Used in testing but made available for general debugging.
+func (p *Buffer) DebugPrint(s string, b []byte) {
+	var u uint64
+
+	obuf := p.buf
+	index := p.index
+	p.buf = b
+	p.index = 0
+	depth := 0
+
+	fmt.Printf("\n--- %s ---\n", s)
+
+out:
+	for {
+		for i := 0; i < depth; i++ {
+			fmt.Print("  ")
+		}
+
+		index := p.index
+		if index == len(p.buf) {
+			break
+		}
+
+		op, err := p.DecodeVarint()
+		if err != nil {
+			fmt.Printf("%3d: fetching op err %v\n", index, err)
+			break out
+		}
+		tag := op >> 3
+		wire := op & 7
+
+		switch wire {
+		default:
+			fmt.Printf("%3d: t=%3d unknown wire=%d\n",
+				index, tag, wire)
+			break out
+
+		case WireBytes:
+			var r []byte
+
+			r, err = p.DecodeRawBytes(false)
+			if err != nil {
+				break out
+			}
+			fmt.Printf("%3d: t=%3d bytes [%d]", index, tag, len(r))
+			if len(r) <= 6 {
+				for i := 0; i < len(r); i++ {
+					fmt.Printf(" %.2x", r[i])
+				}
+			} else {
+				for i := 0; i < 3; i++ {
+					fmt.Printf(" %.2x", r[i])
+				}
+				fmt.Printf(" ..")
+				for i := len(r) - 3; i < len(r); i++ {
+					fmt.Printf(" %.2x", r[i])
+				}
+			}
+			fmt.Printf("\n")
+
+		case WireFixed32:
+			u, err = p.DecodeFixed32()
+			if err != nil {
+				fmt.Printf("%3d: t=%3d fix32 err %v\n", index, tag, err)
+				break out
+			}
+			fmt.Printf("%3d: t=%3d fix32 %d\n", index, tag, u)
+
+		case WireFixed64:
+			u, err = p.DecodeFixed64()
+			if err != nil {
+				fmt.Printf("%3d: t=%3d fix64 err %v\n", index, tag, err)
+				break out
+			}
+			fmt.Printf("%3d: t=%3d fix64 %d\n", index, tag, u)
+
+		case WireVarint:
+			u, err = p.DecodeVarint()
+			if err != nil {
+				fmt.Printf("%3d: t=%3d varint err %v\n", index, tag, err)
+				break out
+			}
+			fmt.Printf("%3d: t=%3d varint %d\n", index, tag, u)
+
+		case WireStartGroup:
+			fmt.Printf("%3d: t=%3d start\n", index, tag)
+			depth++
+
+		case WireEndGroup:
+			depth--
+			fmt.Printf("%3d: t=%3d end\n", index, tag)
+		}
+	}
+
+	if depth != 0 {
+		fmt.Printf("%3d: start-end not balanced %d\n", p.index, depth)
+	}
+	fmt.Printf("\n")
+
+	p.buf = obuf
+	p.index = index
+}
+
+// SetDefaults sets unset protocol buffer fields to their default values.
+// It only modifies fields that are both unset and have defined defaults.
+// It recursively sets default values in any non-nil sub-messages.
+func SetDefaults(pb Message) {
+	setDefaults(reflect.ValueOf(pb), true, false)
+}
+
+// v is a pointer to a struct.
+func setDefaults(v reflect.Value, recur, zeros bool) {
+	v = v.Elem()
+
+	defaultMu.RLock()
+	dm, ok := defaults[v.Type()]
+	defaultMu.RUnlock()
+	if !ok {
+		dm = buildDefaultMessage(v.Type())
+		defaultMu.Lock()
+		defaults[v.Type()] = dm
+		defaultMu.Unlock()
+	}
+
+	for _, sf := range dm.scalars {
+		f := v.Field(sf.index)
+		if !f.IsNil() {
+			// field already set
+			continue
+		}
+		dv := sf.value
+		if dv == nil && !zeros {
+			// no explicit default, and don't want to set zeros
+			continue
+		}
+		fptr := f.Addr().Interface() // **T
+		// TODO: Consider batching the allocations we do here.
+		switch sf.kind {
+		case reflect.Bool:
+			b := new(bool)
+			if dv != nil {
+				*b = dv.(bool)
+			}
+			*(fptr.(**bool)) = b
+		case reflect.Float32:
+			f := new(float32)
+			if dv != nil {
+				*f = dv.(float32)
+			}
+			*(fptr.(**float32)) = f
+		case reflect.Float64:
+			f := new(float64)
+			if dv != nil {
+				*f = dv.(float64)
+			}
+			*(fptr.(**float64)) = f
+		case reflect.Int32:
+			// might be an enum
+			if ft := f.Type(); ft != int32PtrType {
+				// enum
+				f.Set(reflect.New(ft.Elem()))
+				if dv != nil {
+					f.Elem().SetInt(int64(dv.(int32)))
+				}
+			} else {
+				// int32 field
+				i := new(int32)
+				if dv != nil {
+					*i = dv.(int32)
+				}
+				*(fptr.(**int32)) = i
+			}
+		case reflect.Int64:
+			i := new(int64)
+			if dv != nil {
+				*i = dv.(int64)
+			}
+			*(fptr.(**int64)) = i
+		case reflect.String:
+			s := new(string)
+			if dv != nil {
+				*s = dv.(string)
+			}
+			*(fptr.(**string)) = s
+		case reflect.Uint8:
+			// exceptional case: []byte
+			var b []byte
+			if dv != nil {
+				db := dv.([]byte)
+				b = make([]byte, len(db))
+				copy(b, db)
+			} else {
+				b = []byte{}
+			}
+			*(fptr.(*[]byte)) = b
+		case reflect.Uint32:
+			u := new(uint32)
+			if dv != nil {
+				*u = dv.(uint32)
+			}
+			*(fptr.(**uint32)) = u
+		case reflect.Uint64:
+			u := new(uint64)
+			if dv != nil {
+				*u = dv.(uint64)
+			}
+			*(fptr.(**uint64)) = u
+		default:
+			log.Printf("proto: can't set default for field %v (sf.kind=%v)", f, sf.kind)
+		}
+	}
+
+	for _, ni := range dm.nested {
+		f := v.Field(ni)
+		// f is *T or []*T or map[T]*T
+		switch f.Kind() {
+		case reflect.Ptr:
+			if f.IsNil() {
+				continue
+			}
+			setDefaults(f, recur, zeros)
+
+		case reflect.Slice:
+			for i := 0; i < f.Len(); i++ {
+				e := f.Index(i)
+				if e.IsNil() {
+					continue
+				}
+				setDefaults(e, recur, zeros)
+			}
+
+		case reflect.Map:
+			for _, k := range f.MapKeys() {
+				e := f.MapIndex(k)
+				if e.IsNil() {
+					continue
+				}
+				setDefaults(e, recur, zeros)
+			}
+		}
+	}
+}
+
+var (
+	// defaults maps a protocol buffer struct type to a slice of the fields,
+	// with its scalar fields set to their proto-declared non-zero default values.
+	defaultMu sync.RWMutex
+	defaults  = make(map[reflect.Type]defaultMessage)
+
+	int32PtrType = reflect.TypeOf((*int32)(nil))
+)
+
+// defaultMessage represents information about the default values of a message.
+type defaultMessage struct {
+	scalars []scalarField
+	nested  []int // struct field index of nested messages
+}
+
+type scalarField struct {
+	index int          // struct field index
+	kind  reflect.Kind // element type (the T in *T or []T)
+	value interface{}  // the proto-declared default value, or nil
+}
+
+// t is a struct type.
+func buildDefaultMessage(t reflect.Type) (dm defaultMessage) {
+	sprop := GetProperties(t)
+	for _, prop := range sprop.Prop {
+		fi, ok := sprop.decoderTags.get(prop.Tag)
+		if !ok {
+			// XXX_unrecognized
+			continue
+		}
+		ft := t.Field(fi).Type
+
+		sf, nested, err := fieldDefault(ft, prop)
+		switch {
+		case err != nil:
+			log.Print(err)
+		case nested:
+			dm.nested = append(dm.nested, fi)
+		case sf != nil:
+			sf.index = fi
+			dm.scalars = append(dm.scalars, *sf)
+		}
+	}
+
+	return dm
+}
+
+// fieldDefault returns the scalarField for field type ft.
+// sf will be nil if the field can not have a default.
+// nestedMessage will be true if this is a nested message.
+// Note that sf.index is not set on return.
+func fieldDefault(ft reflect.Type, prop *Properties) (sf *scalarField, nestedMessage bool, err error) {
+	var canHaveDefault bool
+	switch ft.Kind() {
+	case reflect.Ptr:
+		if ft.Elem().Kind() == reflect.Struct {
+			nestedMessage = true
+		} else {
+			canHaveDefault = true // proto2 scalar field
+		}
+
+	case reflect.Slice:
+		switch ft.Elem().Kind() {
+		case reflect.Ptr:
+			nestedMessage = true // repeated message
+		case reflect.Uint8:
+			canHaveDefault = true // bytes field
+		}
+
+	case reflect.Map:
+		if ft.Elem().Kind() == reflect.Ptr {
+			nestedMessage = true // map with message values
+		}
+	}
+
+	if !canHaveDefault {
+		if nestedMessage {
+			return nil, true, nil
+		}
+		return nil, false, nil
+	}
+
+	// We now know that ft is a pointer or slice.
+	sf = &scalarField{kind: ft.Elem().Kind()}
+
+	// scalar fields without defaults
+	if !prop.HasDefault {
+		return sf, false, nil
+	}
+
+	// a scalar field: either *T or []byte
+	switch ft.Elem().Kind() {
+	case reflect.Bool:
+		x, err := strconv.ParseBool(prop.Default)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default bool %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	case reflect.Float32:
+		x, err := strconv.ParseFloat(prop.Default, 32)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default float32 %q: %v", prop.Default, err)
+		}
+		sf.value = float32(x)
+	case reflect.Float64:
+		x, err := strconv.ParseFloat(prop.Default, 64)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default float64 %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	case reflect.Int32:
+		x, err := strconv.ParseInt(prop.Default, 10, 32)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default int32 %q: %v", prop.Default, err)
+		}
+		sf.value = int32(x)
+	case reflect.Int64:
+		x, err := strconv.ParseInt(prop.Default, 10, 64)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default int64 %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	case reflect.String:
+		sf.value = prop.Default
+	case reflect.Uint8:
+		// []byte (not *uint8)
+		sf.value = []byte(prop.Default)
+	case reflect.Uint32:
+		x, err := strconv.ParseUint(prop.Default, 10, 32)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default uint32 %q: %v", prop.Default, err)
+		}
+		sf.value = uint32(x)
+	case reflect.Uint64:
+		x, err := strconv.ParseUint(prop.Default, 10, 64)
+		if err != nil {
+			return nil, false, fmt.Errorf("proto: bad default uint64 %q: %v", prop.Default, err)
+		}
+		sf.value = x
+	default:
+		return nil, false, fmt.Errorf("proto: unhandled def kind %v", ft.Elem().Kind())
+	}
+
+	return sf, false, nil
+}
+
+// Map fields may have key types of non-float scalars, strings and enums.
+// The easiest way to sort them in some deterministic order is to use fmt.
+// If this turns out to be inefficient we can always consider other options,
+// such as doing a Schwartzian transform.
+
+func mapKeys(vs []reflect.Value) sort.Interface {
+	s := mapKeySorter{
+		vs: vs,
+		// default Less function: textual comparison
+		less: func(a, b reflect.Value) bool {
+			return fmt.Sprint(a.Interface()) < fmt.Sprint(b.Interface())
+		},
+	}
+
+	// Type specialization per https://developers.google.com/protocol-buffers/docs/proto#maps;
+	// numeric keys are sorted numerically.
+	if len(vs) == 0 {
+		return s
+	}
+	switch vs[0].Kind() {
+	case reflect.Int32, reflect.Int64:
+		s.less = func(a, b reflect.Value) bool { return a.Int() < b.Int() }
+	case reflect.Uint32, reflect.Uint64:
+		s.less = func(a, b reflect.Value) bool { return a.Uint() < b.Uint() }
+	}
+
+	return s
+}
+
+type mapKeySorter struct {
+	vs   []reflect.Value
+	less func(a, b reflect.Value) bool
+}
+
+func (s mapKeySorter) Len() int      { return len(s.vs) }
+func (s mapKeySorter) Swap(i, j int) { s.vs[i], s.vs[j] = s.vs[j], s.vs[i] }
+func (s mapKeySorter) Less(i, j int) bool {
+	return s.less(s.vs[i], s.vs[j])
+}
+
+// isProto3Zero reports whether v is a zero proto3 value.
+func isProto3Zero(v reflect.Value) bool {
+	switch v.Kind() {
+	case reflect.Bool:
+		return !v.Bool()
+	case reflect.Int32, reflect.Int64:
+		return v.Int() == 0
+	case reflect.Uint32, reflect.Uint64:
+		return v.Uint() == 0
+	case reflect.Float32, reflect.Float64:
+		return v.Float() == 0
+	case reflect.String:
+		return v.String() == ""
+	}
+	return false
+}
+
+// ProtoPackageIsVersion2 is referenced from generated protocol buffer files
+// to assert that that code is compatible with this version of the proto package.
+const ProtoPackageIsVersion2 = true
+
+// ProtoPackageIsVersion1 is referenced from generated protocol buffer files
+// to assert that that code is compatible with this version of the proto package.
+const ProtoPackageIsVersion1 = true

vendor/github.com/golang/protobuf/proto/message_set.go

@@ -0,0 +1,311 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Support for message sets.
+ */
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"reflect"
+	"sort"
+)
+
+// errNoMessageTypeID occurs when a protocol buffer does not have a message type ID.
+// A message type ID is required for storing a protocol buffer in a message set.
+var errNoMessageTypeID = errors.New("proto does not have a message type ID")
+
+// The first two types (_MessageSet_Item and messageSet)
+// model what the protocol compiler produces for the following protocol message:
+//   message MessageSet {
+//     repeated group Item = 1 {
+//       required int32 type_id = 2;
+//       required string message = 3;
+//     };
+//   }
+// That is the MessageSet wire format. We can't use a proto to generate these
+// because that would introduce a circular dependency between it and this package.
+
+type _MessageSet_Item struct {
+	TypeId  *int32 `protobuf:"varint,2,req,name=type_id"`
+	Message []byte `protobuf:"bytes,3,req,name=message"`
+}
+
+type messageSet struct {
+	Item             []*_MessageSet_Item `protobuf:"group,1,rep"`
+	XXX_unrecognized []byte
+	// TODO: caching?
+}
+
+// Make sure messageSet is a Message.
+var _ Message = (*messageSet)(nil)
+
+// messageTypeIder is an interface satisfied by a protocol buffer type
+// that may be stored in a MessageSet.
+type messageTypeIder interface {
+	MessageTypeId() int32
+}
+
+func (ms *messageSet) find(pb Message) *_MessageSet_Item {
+	mti, ok := pb.(messageTypeIder)
+	if !ok {
+		return nil
+	}
+	id := mti.MessageTypeId()
+	for _, item := range ms.Item {
+		if *item.TypeId == id {
+			return item
+		}
+	}
+	return nil
+}
+
+func (ms *messageSet) Has(pb Message) bool {
+	if ms.find(pb) != nil {
+		return true
+	}
+	return false
+}
+
+func (ms *messageSet) Unmarshal(pb Message) error {
+	if item := ms.find(pb); item != nil {
+		return Unmarshal(item.Message, pb)
+	}
+	if _, ok := pb.(messageTypeIder); !ok {
+		return errNoMessageTypeID
+	}
+	return nil // TODO: return error instead?
+}
+
+func (ms *messageSet) Marshal(pb Message) error {
+	msg, err := Marshal(pb)
+	if err != nil {
+		return err
+	}
+	if item := ms.find(pb); item != nil {
+		// reuse existing item
+		item.Message = msg
+		return nil
+	}
+
+	mti, ok := pb.(messageTypeIder)
+	if !ok {
+		return errNoMessageTypeID
+	}
+
+	mtid := mti.MessageTypeId()
+	ms.Item = append(ms.Item, &_MessageSet_Item{
+		TypeId:  &mtid,
+		Message: msg,
+	})
+	return nil
+}
+
+func (ms *messageSet) Reset()         { *ms = messageSet{} }
+func (ms *messageSet) String() string { return CompactTextString(ms) }
+func (*messageSet) ProtoMessage()     {}
+
+// Support for the message_set_wire_format message option.
+
+func skipVarint(buf []byte) []byte {
+	i := 0
+	for ; buf[i]&0x80 != 0; i++ {
+	}
+	return buf[i+1:]
+}
+
+// MarshalMessageSet encodes the extension map represented by m in the message set wire format.
+// It is called by generated Marshal methods on protocol buffer messages with the message_set_wire_format option.
+func MarshalMessageSet(exts interface{}) ([]byte, error) {
+	var m map[int32]Extension
+	switch exts := exts.(type) {
+	case *XXX_InternalExtensions:
+		if err := encodeExtensions(exts); err != nil {
+			return nil, err
+		}
+		m, _ = exts.extensionsRead()
+	case map[int32]Extension:
+		if err := encodeExtensionsMap(exts); err != nil {
+			return nil, err
+		}
+		m = exts
+	default:
+		return nil, errors.New("proto: not an extension map")
+	}
+
+	// Sort extension IDs to provide a deterministic encoding.
+	// See also enc_map in encode.go.
+	ids := make([]int, 0, len(m))
+	for id := range m {
+		ids = append(ids, int(id))
+	}
+	sort.Ints(ids)
+
+	ms := &messageSet{Item: make([]*_MessageSet_Item, 0, len(m))}
+	for _, id := range ids {
+		e := m[int32(id)]
+		// Remove the wire type and field number varint, as well as the length varint.
+		msg := skipVarint(skipVarint(e.enc))
+
+		ms.Item = append(ms.Item, &_MessageSet_Item{
+			TypeId:  Int32(int32(id)),
+			Message: msg,
+		})
+	}
+	return Marshal(ms)
+}
+
+// UnmarshalMessageSet decodes the extension map encoded in buf in the message set wire format.
+// It is called by generated Unmarshal methods on protocol buffer messages with the message_set_wire_format option.
+func UnmarshalMessageSet(buf []byte, exts interface{}) error {
+	var m map[int32]Extension
+	switch exts := exts.(type) {
+	case *XXX_InternalExtensions:
+		m = exts.extensionsWrite()
+	case map[int32]Extension:
+		m = exts
+	default:
+		return errors.New("proto: not an extension map")
+	}
+
+	ms := new(messageSet)
+	if err := Unmarshal(buf, ms); err != nil {
+		return err
+	}
+	for _, item := range ms.Item {
+		id := *item.TypeId
+		msg := item.Message
+
+		// Restore wire type and field number varint, plus length varint.
+		// Be careful to preserve duplicate items.
+		b := EncodeVarint(uint64(id)<<3 | WireBytes)
+		if ext, ok := m[id]; ok {
+			// Existing data; rip off the tag and length varint
+			// so we join the new data correctly.
+			// We can assume that ext.enc is set because we are unmarshaling.
+			o := ext.enc[len(b):]   // skip wire type and field number
+			_, n := DecodeVarint(o) // calculate length of length varint
+			o = o[n:]               // skip length varint
+			msg = append(o, msg...) // join old data and new data
+		}
+		b = append(b, EncodeVarint(uint64(len(msg)))...)
+		b = append(b, msg...)
+
+		m[id] = Extension{enc: b}
+	}
+	return nil
+}
+
+// MarshalMessageSetJSON encodes the extension map represented by m in JSON format.
+// It is called by generated MarshalJSON methods on protocol buffer messages with the message_set_wire_format option.
+func MarshalMessageSetJSON(exts interface{}) ([]byte, error) {
+	var m map[int32]Extension
+	switch exts := exts.(type) {
+	case *XXX_InternalExtensions:
+		m, _ = exts.extensionsRead()
+	case map[int32]Extension:
+		m = exts
+	default:
+		return nil, errors.New("proto: not an extension map")
+	}
+	var b bytes.Buffer
+	b.WriteByte('{')
+
+	// Process the map in key order for deterministic output.
+	ids := make([]int32, 0, len(m))
+	for id := range m {
+		ids = append(ids, id)
+	}
+	sort.Sort(int32Slice(ids)) // int32Slice defined in text.go
+
+	for i, id := range ids {
+		ext := m[id]
+		if i > 0 {
+			b.WriteByte(',')
+		}
+
+		msd, ok := messageSetMap[id]
+		if !ok {
+			// Unknown type; we can't render it, so skip it.
+			continue
+		}
+		fmt.Fprintf(&b, `"[%s]":`, msd.name)
+
+		x := ext.value
+		if x == nil {
+			x = reflect.New(msd.t.Elem()).Interface()
+			if err := Unmarshal(ext.enc, x.(Message)); err != nil {
+				return nil, err
+			}
+		}
+		d, err := json.Marshal(x)
+		if err != nil {
+			return nil, err
+		}
+		b.Write(d)
+	}
+	b.WriteByte('}')
+	return b.Bytes(), nil
+}
+
+// UnmarshalMessageSetJSON decodes the extension map encoded in buf in JSON format.
+// It is called by generated UnmarshalJSON methods on protocol buffer messages with the message_set_wire_format option.
+func UnmarshalMessageSetJSON(buf []byte, exts interface{}) error {
+	// Common-case fast path.
+	if len(buf) == 0 || bytes.Equal(buf, []byte("{}")) {
+		return nil
+	}
+
+	// This is fairly tricky, and it's not clear that it is needed.
+	return errors.New("TODO: UnmarshalMessageSetJSON not yet implemented")
+}
+
+// A global registry of types that can be used in a MessageSet.
+
+var messageSetMap = make(map[int32]messageSetDesc)
+
+type messageSetDesc struct {
+	t    reflect.Type // pointer to struct
+	name string
+}
+
+// RegisterMessageSetType is called from the generated code.
+func RegisterMessageSetType(m Message, fieldNum int32, name string) {
+	messageSetMap[fieldNum] = messageSetDesc{
+		t:    reflect.TypeOf(m),
+		name: name,
+	}
+}

vendor/github.com/golang/protobuf/proto/pointer_reflect.go

@@ -0,0 +1,484 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2012 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// +build appengine js
+
+// This file contains an implementation of proto field accesses using package reflect.
+// It is slower than the code in pointer_unsafe.go but it avoids package unsafe and can
+// be used on App Engine.
+
+package proto
+
+import (
+	"math"
+	"reflect"
+)
+
+// A structPointer is a pointer to a struct.
+type structPointer struct {
+	v reflect.Value
+}
+
+// toStructPointer returns a structPointer equivalent to the given reflect value.
+// The reflect value must itself be a pointer to a struct.
+func toStructPointer(v reflect.Value) structPointer {
+	return structPointer{v}
+}
+
+// IsNil reports whether p is nil.
+func structPointer_IsNil(p structPointer) bool {
+	return p.v.IsNil()
+}
+
+// Interface returns the struct pointer as an interface value.
+func structPointer_Interface(p structPointer, _ reflect.Type) interface{} {
+	return p.v.Interface()
+}
+
+// A field identifies a field in a struct, accessible from a structPointer.
+// In this implementation, a field is identified by the sequence of field indices
+// passed to reflect's FieldByIndex.
+type field []int
+
+// toField returns a field equivalent to the given reflect field.
+func toField(f *reflect.StructField) field {
+	return f.Index
+}
+
+// invalidField is an invalid field identifier.
+var invalidField = field(nil)
+
+// IsValid reports whether the field identifier is valid.
+func (f field) IsValid() bool { return f != nil }
+
+// field returns the given field in the struct as a reflect value.
+func structPointer_field(p structPointer, f field) reflect.Value {
+	// Special case: an extension map entry with a value of type T
+	// passes a *T to the struct-handling code with a zero field,
+	// expecting that it will be treated as equivalent to *struct{ X T },
+	// which has the same memory layout. We have to handle that case
+	// specially, because reflect will panic if we call FieldByIndex on a
+	// non-struct.
+	if f == nil {
+		return p.v.Elem()
+	}
+
+	return p.v.Elem().FieldByIndex(f)
+}
+
+// ifield returns the given field in the struct as an interface value.
+func structPointer_ifield(p structPointer, f field) interface{} {
+	return structPointer_field(p, f).Addr().Interface()
+}
+
+// Bytes returns the address of a []byte field in the struct.
+func structPointer_Bytes(p structPointer, f field) *[]byte {
+	return structPointer_ifield(p, f).(*[]byte)
+}
+
+// BytesSlice returns the address of a [][]byte field in the struct.
+func structPointer_BytesSlice(p structPointer, f field) *[][]byte {
+	return structPointer_ifield(p, f).(*[][]byte)
+}
+
+// Bool returns the address of a *bool field in the struct.
+func structPointer_Bool(p structPointer, f field) **bool {
+	return structPointer_ifield(p, f).(**bool)
+}
+
+// BoolVal returns the address of a bool field in the struct.
+func structPointer_BoolVal(p structPointer, f field) *bool {
+	return structPointer_ifield(p, f).(*bool)
+}
+
+// BoolSlice returns the address of a []bool field in the struct.
+func structPointer_BoolSlice(p structPointer, f field) *[]bool {
+	return structPointer_ifield(p, f).(*[]bool)
+}
+
+// String returns the address of a *string field in the struct.
+func structPointer_String(p structPointer, f field) **string {
+	return structPointer_ifield(p, f).(**string)
+}
+
+// StringVal returns the address of a string field in the struct.
+func structPointer_StringVal(p structPointer, f field) *string {
+	return structPointer_ifield(p, f).(*string)
+}
+
+// StringSlice returns the address of a []string field in the struct.
+func structPointer_StringSlice(p structPointer, f field) *[]string {
+	return structPointer_ifield(p, f).(*[]string)
+}
+
+// Extensions returns the address of an extension map field in the struct.
+func structPointer_Extensions(p structPointer, f field) *XXX_InternalExtensions {
+	return structPointer_ifield(p, f).(*XXX_InternalExtensions)
+}
+
+// ExtMap returns the address of an extension map field in the struct.
+func structPointer_ExtMap(p structPointer, f field) *map[int32]Extension {
+	return structPointer_ifield(p, f).(*map[int32]Extension)
+}
+
+// NewAt returns the reflect.Value for a pointer to a field in the struct.
+func structPointer_NewAt(p structPointer, f field, typ reflect.Type) reflect.Value {
+	return structPointer_field(p, f).Addr()
+}
+
+// SetStructPointer writes a *struct field in the struct.
+func structPointer_SetStructPointer(p structPointer, f field, q structPointer) {
+	structPointer_field(p, f).Set(q.v)
+}
+
+// GetStructPointer reads a *struct field in the struct.
+func structPointer_GetStructPointer(p structPointer, f field) structPointer {
+	return structPointer{structPointer_field(p, f)}
+}
+
+// StructPointerSlice the address of a []*struct field in the struct.
+func structPointer_StructPointerSlice(p structPointer, f field) structPointerSlice {
+	return structPointerSlice{structPointer_field(p, f)}
+}
+
+// A structPointerSlice represents the address of a slice of pointers to structs
+// (themselves messages or groups). That is, v.Type() is *[]*struct{...}.
+type structPointerSlice struct {
+	v reflect.Value
+}
+
+func (p structPointerSlice) Len() int                  { return p.v.Len() }
+func (p structPointerSlice) Index(i int) structPointer { return structPointer{p.v.Index(i)} }
+func (p structPointerSlice) Append(q structPointer) {
+	p.v.Set(reflect.Append(p.v, q.v))
+}
+
+var (
+	int32Type   = reflect.TypeOf(int32(0))
+	uint32Type  = reflect.TypeOf(uint32(0))
+	float32Type = reflect.TypeOf(float32(0))
+	int64Type   = reflect.TypeOf(int64(0))
+	uint64Type  = reflect.TypeOf(uint64(0))
+	float64Type = reflect.TypeOf(float64(0))
+)
+
+// A word32 represents a field of type *int32, *uint32, *float32, or *enum.
+// That is, v.Type() is *int32, *uint32, *float32, or *enum and v is assignable.
+type word32 struct {
+	v reflect.Value
+}
+
+// IsNil reports whether p is nil.
+func word32_IsNil(p word32) bool {
+	return p.v.IsNil()
+}
+
+// Set sets p to point at a newly allocated word with bits set to x.
+func word32_Set(p word32, o *Buffer, x uint32) {
+	t := p.v.Type().Elem()
+	switch t {
+	case int32Type:
+		if len(o.int32s) == 0 {
+			o.int32s = make([]int32, uint32PoolSize)
+		}
+		o.int32s[0] = int32(x)
+		p.v.Set(reflect.ValueOf(&o.int32s[0]))
+		o.int32s = o.int32s[1:]
+		return
+	case uint32Type:
+		if len(o.uint32s) == 0 {
+			o.uint32s = make([]uint32, uint32PoolSize)
+		}
+		o.uint32s[0] = x
+		p.v.Set(reflect.ValueOf(&o.uint32s[0]))
+		o.uint32s = o.uint32s[1:]
+		return
+	case float32Type:
+		if len(o.float32s) == 0 {
+			o.float32s = make([]float32, uint32PoolSize)
+		}
+		o.float32s[0] = math.Float32frombits(x)
+		p.v.Set(reflect.ValueOf(&o.float32s[0]))
+		o.float32s = o.float32s[1:]
+		return
+	}
+
+	// must be enum
+	p.v.Set(reflect.New(t))
+	p.v.Elem().SetInt(int64(int32(x)))
+}
+
+// Get gets the bits pointed at by p, as a uint32.
+func word32_Get(p word32) uint32 {
+	elem := p.v.Elem()
+	switch elem.Kind() {
+	case reflect.Int32:
+		return uint32(elem.Int())
+	case reflect.Uint32:
+		return uint32(elem.Uint())
+	case reflect.Float32:
+		return math.Float32bits(float32(elem.Float()))
+	}
+	panic("unreachable")
+}
+
+// Word32 returns a reference to a *int32, *uint32, *float32, or *enum field in the struct.
+func structPointer_Word32(p structPointer, f field) word32 {
+	return word32{structPointer_field(p, f)}
+}
+
+// A word32Val represents a field of type int32, uint32, float32, or enum.
+// That is, v.Type() is int32, uint32, float32, or enum and v is assignable.
+type word32Val struct {
+	v reflect.Value
+}
+
+// Set sets *p to x.
+func word32Val_Set(p word32Val, x uint32) {
+	switch p.v.Type() {
+	case int32Type:
+		p.v.SetInt(int64(x))
+		return
+	case uint32Type:
+		p.v.SetUint(uint64(x))
+		return
+	case float32Type:
+		p.v.SetFloat(float64(math.Float32frombits(x)))
+		return
+	}
+
+	// must be enum
+	p.v.SetInt(int64(int32(x)))
+}
+
+// Get gets the bits pointed at by p, as a uint32.
+func word32Val_Get(p word32Val) uint32 {
+	elem := p.v
+	switch elem.Kind() {
+	case reflect.Int32:
+		return uint32(elem.Int())
+	case reflect.Uint32:
+		return uint32(elem.Uint())
+	case reflect.Float32:
+		return math.Float32bits(float32(elem.Float()))
+	}
+	panic("unreachable")
+}
+
+// Word32Val returns a reference to a int32, uint32, float32, or enum field in the struct.
+func structPointer_Word32Val(p structPointer, f field) word32Val {
+	return word32Val{structPointer_field(p, f)}
+}
+
+// A word32Slice is a slice of 32-bit values.
+// That is, v.Type() is []int32, []uint32, []float32, or []enum.
+type word32Slice struct {
+	v reflect.Value
+}
+
+func (p word32Slice) Append(x uint32) {
+	n, m := p.v.Len(), p.v.Cap()
+	if n < m {
+		p.v.SetLen(n + 1)
+	} else {
+		t := p.v.Type().Elem()
+		p.v.Set(reflect.Append(p.v, reflect.Zero(t)))
+	}
+	elem := p.v.Index(n)
+	switch elem.Kind() {
+	case reflect.Int32:
+		elem.SetInt(int64(int32(x)))
+	case reflect.Uint32:
+		elem.SetUint(uint64(x))
+	case reflect.Float32:
+		elem.SetFloat(float64(math.Float32frombits(x)))
+	}
+}
+
+func (p word32Slice) Len() int {
+	return p.v.Len()
+}
+
+func (p word32Slice) Index(i int) uint32 {
+	elem := p.v.Index(i)
+	switch elem.Kind() {
+	case reflect.Int32:
+		return uint32(elem.Int())
+	case reflect.Uint32:
+		return uint32(elem.Uint())
+	case reflect.Float32:
+		return math.Float32bits(float32(elem.Float()))
+	}
+	panic("unreachable")
+}
+
+// Word32Slice returns a reference to a []int32, []uint32, []float32, or []enum field in the struct.
+func structPointer_Word32Slice(p structPointer, f field) word32Slice {
+	return word32Slice{structPointer_field(p, f)}
+}
+
+// word64 is like word32 but for 64-bit values.
+type word64 struct {
+	v reflect.Value
+}
+
+func word64_Set(p word64, o *Buffer, x uint64) {
+	t := p.v.Type().Elem()
+	switch t {
+	case int64Type:
+		if len(o.int64s) == 0 {
+			o.int64s = make([]int64, uint64PoolSize)
+		}
+		o.int64s[0] = int64(x)
+		p.v.Set(reflect.ValueOf(&o.int64s[0]))
+		o.int64s = o.int64s[1:]
+		return
+	case uint64Type:
+		if len(o.uint64s) == 0 {
+			o.uint64s = make([]uint64, uint64PoolSize)
+		}
+		o.uint64s[0] = x
+		p.v.Set(reflect.ValueOf(&o.uint64s[0]))
+		o.uint64s = o.uint64s[1:]
+		return
+	case float64Type:
+		if len(o.float64s) == 0 {
+			o.float64s = make([]float64, uint64PoolSize)
+		}
+		o.float64s[0] = math.Float64frombits(x)
+		p.v.Set(reflect.ValueOf(&o.float64s[0]))
+		o.float64s = o.float64s[1:]
+		return
+	}
+	panic("unreachable")
+}
+
+func word64_IsNil(p word64) bool {
+	return p.v.IsNil()
+}
+
+func word64_Get(p word64) uint64 {
+	elem := p.v.Elem()
+	switch elem.Kind() {
+	case reflect.Int64:
+		return uint64(elem.Int())
+	case reflect.Uint64:
+		return elem.Uint()
+	case reflect.Float64:
+		return math.Float64bits(elem.Float())
+	}
+	panic("unreachable")
+}
+
+func structPointer_Word64(p structPointer, f field) word64 {
+	return word64{structPointer_field(p, f)}
+}
+
+// word64Val is like word32Val but for 64-bit values.
+type word64Val struct {
+	v reflect.Value
+}
+
+func word64Val_Set(p word64Val, o *Buffer, x uint64) {
+	switch p.v.Type() {
+	case int64Type:
+		p.v.SetInt(int64(x))
+		return
+	case uint64Type:
+		p.v.SetUint(x)
+		return
+	case float64Type:
+		p.v.SetFloat(math.Float64frombits(x))
+		return
+	}
+	panic("unreachable")
+}
+
+func word64Val_Get(p word64Val) uint64 {
+	elem := p.v
+	switch elem.Kind() {
+	case reflect.Int64:
+		return uint64(elem.Int())
+	case reflect.Uint64:
+		return elem.Uint()
+	case reflect.Float64:
+		return math.Float64bits(elem.Float())
+	}
+	panic("unreachable")
+}
+
+func structPointer_Word64Val(p structPointer, f field) word64Val {
+	return word64Val{structPointer_field(p, f)}
+}
+
+type word64Slice struct {
+	v reflect.Value
+}
+
+func (p word64Slice) Append(x uint64) {
+	n, m := p.v.Len(), p.v.Cap()
+	if n < m {
+		p.v.SetLen(n + 1)
+	} else {
+		t := p.v.Type().Elem()
+		p.v.Set(reflect.Append(p.v, reflect.Zero(t)))
+	}
+	elem := p.v.Index(n)
+	switch elem.Kind() {
+	case reflect.Int64:
+		elem.SetInt(int64(int64(x)))
+	case reflect.Uint64:
+		elem.SetUint(uint64(x))
+	case reflect.Float64:
+		elem.SetFloat(float64(math.Float64frombits(x)))
+	}
+}
+
+func (p word64Slice) Len() int {
+	return p.v.Len()
+}
+
+func (p word64Slice) Index(i int) uint64 {
+	elem := p.v.Index(i)
+	switch elem.Kind() {
+	case reflect.Int64:
+		return uint64(elem.Int())
+	case reflect.Uint64:
+		return uint64(elem.Uint())
+	case reflect.Float64:
+		return math.Float64bits(float64(elem.Float()))
+	}
+	panic("unreachable")
+}
+
+func structPointer_Word64Slice(p structPointer, f field) word64Slice {
+	return word64Slice{structPointer_field(p, f)}
+}

vendor/github.com/golang/protobuf/proto/pointer_unsafe.go

@@ -0,0 +1,270 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2012 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// +build !appengine,!js
+
+// This file contains the implementation of the proto field accesses using package unsafe.
+
+package proto
+
+import (
+	"reflect"
+	"unsafe"
+)
+
+// NOTE: These type_Foo functions would more idiomatically be methods,
+// but Go does not allow methods on pointer types, and we must preserve
+// some pointer type for the garbage collector. We use these
+// funcs with clunky names as our poor approximation to methods.
+//
+// An alternative would be
+//	type structPointer struct { p unsafe.Pointer }
+// but that does not registerize as well.
+
+// A structPointer is a pointer to a struct.
+type structPointer unsafe.Pointer
+
+// toStructPointer returns a structPointer equivalent to the given reflect value.
+func toStructPointer(v reflect.Value) structPointer {
+	return structPointer(unsafe.Pointer(v.Pointer()))
+}
+
+// IsNil reports whether p is nil.
+func structPointer_IsNil(p structPointer) bool {
+	return p == nil
+}
+
+// Interface returns the struct pointer, assumed to have element type t,
+// as an interface value.
+func structPointer_Interface(p structPointer, t reflect.Type) interface{} {
+	return reflect.NewAt(t, unsafe.Pointer(p)).Interface()
+}
+
+// A field identifies a field in a struct, accessible from a structPointer.
+// In this implementation, a field is identified by its byte offset from the start of the struct.
+type field uintptr
+
+// toField returns a field equivalent to the given reflect field.
+func toField(f *reflect.StructField) field {
+	return field(f.Offset)
+}
+
+// invalidField is an invalid field identifier.
+const invalidField = ^field(0)
+
+// IsValid reports whether the field identifier is valid.
+func (f field) IsValid() bool {
+	return f != ^field(0)
+}
+
+// Bytes returns the address of a []byte field in the struct.
+func structPointer_Bytes(p structPointer, f field) *[]byte {
+	return (*[]byte)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// BytesSlice returns the address of a [][]byte field in the struct.
+func structPointer_BytesSlice(p structPointer, f field) *[][]byte {
+	return (*[][]byte)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// Bool returns the address of a *bool field in the struct.
+func structPointer_Bool(p structPointer, f field) **bool {
+	return (**bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// BoolVal returns the address of a bool field in the struct.
+func structPointer_BoolVal(p structPointer, f field) *bool {
+	return (*bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// BoolSlice returns the address of a []bool field in the struct.
+func structPointer_BoolSlice(p structPointer, f field) *[]bool {
+	return (*[]bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// String returns the address of a *string field in the struct.
+func structPointer_String(p structPointer, f field) **string {
+	return (**string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// StringVal returns the address of a string field in the struct.
+func structPointer_StringVal(p structPointer, f field) *string {
+	return (*string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// StringSlice returns the address of a []string field in the struct.
+func structPointer_StringSlice(p structPointer, f field) *[]string {
+	return (*[]string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// ExtMap returns the address of an extension map field in the struct.
+func structPointer_Extensions(p structPointer, f field) *XXX_InternalExtensions {
+	return (*XXX_InternalExtensions)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+func structPointer_ExtMap(p structPointer, f field) *map[int32]Extension {
+	return (*map[int32]Extension)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// NewAt returns the reflect.Value for a pointer to a field in the struct.
+func structPointer_NewAt(p structPointer, f field, typ reflect.Type) reflect.Value {
+	return reflect.NewAt(typ, unsafe.Pointer(uintptr(p)+uintptr(f)))
+}
+
+// SetStructPointer writes a *struct field in the struct.
+func structPointer_SetStructPointer(p structPointer, f field, q structPointer) {
+	*(*structPointer)(unsafe.Pointer(uintptr(p) + uintptr(f))) = q
+}
+
+// GetStructPointer reads a *struct field in the struct.
+func structPointer_GetStructPointer(p structPointer, f field) structPointer {
+	return *(*structPointer)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// StructPointerSlice the address of a []*struct field in the struct.
+func structPointer_StructPointerSlice(p structPointer, f field) *structPointerSlice {
+	return (*structPointerSlice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// A structPointerSlice represents a slice of pointers to structs (themselves submessages or groups).
+type structPointerSlice []structPointer
+
+func (v *structPointerSlice) Len() int                  { return len(*v) }
+func (v *structPointerSlice) Index(i int) structPointer { return (*v)[i] }
+func (v *structPointerSlice) Append(p structPointer)    { *v = append(*v, p) }
+
+// A word32 is the address of a "pointer to 32-bit value" field.
+type word32 **uint32
+
+// IsNil reports whether *v is nil.
+func word32_IsNil(p word32) bool {
+	return *p == nil
+}
+
+// Set sets *v to point at a newly allocated word set to x.
+func word32_Set(p word32, o *Buffer, x uint32) {
+	if len(o.uint32s) == 0 {
+		o.uint32s = make([]uint32, uint32PoolSize)
+	}
+	o.uint32s[0] = x
+	*p = &o.uint32s[0]
+	o.uint32s = o.uint32s[1:]
+}
+
+// Get gets the value pointed at by *v.
+func word32_Get(p word32) uint32 {
+	return **p
+}
+
+// Word32 returns the address of a *int32, *uint32, *float32, or *enum field in the struct.
+func structPointer_Word32(p structPointer, f field) word32 {
+	return word32((**uint32)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+}
+
+// A word32Val is the address of a 32-bit value field.
+type word32Val *uint32
+
+// Set sets *p to x.
+func word32Val_Set(p word32Val, x uint32) {
+	*p = x
+}
+
+// Get gets the value pointed at by p.
+func word32Val_Get(p word32Val) uint32 {
+	return *p
+}
+
+// Word32Val returns the address of a *int32, *uint32, *float32, or *enum field in the struct.
+func structPointer_Word32Val(p structPointer, f field) word32Val {
+	return word32Val((*uint32)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+}
+
+// A word32Slice is a slice of 32-bit values.
+type word32Slice []uint32
+
+func (v *word32Slice) Append(x uint32)    { *v = append(*v, x) }
+func (v *word32Slice) Len() int           { return len(*v) }
+func (v *word32Slice) Index(i int) uint32 { return (*v)[i] }
+
+// Word32Slice returns the address of a []int32, []uint32, []float32, or []enum field in the struct.
+func structPointer_Word32Slice(p structPointer, f field) *word32Slice {
+	return (*word32Slice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}
+
+// word64 is like word32 but for 64-bit values.
+type word64 **uint64
+
+func word64_Set(p word64, o *Buffer, x uint64) {
+	if len(o.uint64s) == 0 {
+		o.uint64s = make([]uint64, uint64PoolSize)
+	}
+	o.uint64s[0] = x
+	*p = &o.uint64s[0]
+	o.uint64s = o.uint64s[1:]
+}
+
+func word64_IsNil(p word64) bool {
+	return *p == nil
+}
+
+func word64_Get(p word64) uint64 {
+	return **p
+}
+
+func structPointer_Word64(p structPointer, f field) word64 {
+	return word64((**uint64)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+}
+
+// word64Val is like word32Val but for 64-bit values.
+type word64Val *uint64
+
+func word64Val_Set(p word64Val, o *Buffer, x uint64) {
+	*p = x
+}
+
+func word64Val_Get(p word64Val) uint64 {
+	return *p
+}
+
+func structPointer_Word64Val(p structPointer, f field) word64Val {
+	return word64Val((*uint64)(unsafe.Pointer(uintptr(p) + uintptr(f))))
+}
+
+// word64Slice is like word32Slice but for 64-bit values.
+type word64Slice []uint64
+
+func (v *word64Slice) Append(x uint64)    { *v = append(*v, x) }
+func (v *word64Slice) Len() int           { return len(*v) }
+func (v *word64Slice) Index(i int) uint64 { return (*v)[i] }
+
+func structPointer_Word64Slice(p structPointer, f field) *word64Slice {
+	return (*word64Slice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
+}

vendor/github.com/golang/protobuf/proto/properties.go

@@ -0,0 +1,872 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+/*
+ * Routines for encoding data into the wire format for protocol buffers.
+ */
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"reflect"
+	"sort"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+const debug bool = false
+
+// Constants that identify the encoding of a value on the wire.
+const (
+	WireVarint     = 0
+	WireFixed64    = 1
+	WireBytes      = 2
+	WireStartGroup = 3
+	WireEndGroup   = 4
+	WireFixed32    = 5
+)
+
+const startSize = 10 // initial slice/string sizes
+
+// Encoders are defined in encode.go
+// An encoder outputs the full representation of a field, including its
+// tag and encoder type.
+type encoder func(p *Buffer, prop *Properties, base structPointer) error
+
+// A valueEncoder encodes a single integer in a particular encoding.
+type valueEncoder func(o *Buffer, x uint64) error
+
+// Sizers are defined in encode.go
+// A sizer returns the encoded size of a field, including its tag and encoder
+// type.
+type sizer func(prop *Properties, base structPointer) int
+
+// A valueSizer returns the encoded size of a single integer in a particular
+// encoding.
+type valueSizer func(x uint64) int
+
+// Decoders are defined in decode.go
+// A decoder creates a value from its wire representation.
+// Unrecognized subelements are saved in unrec.
+type decoder func(p *Buffer, prop *Properties, base structPointer) error
+
+// A valueDecoder decodes a single integer in a particular encoding.
+type valueDecoder func(o *Buffer) (x uint64, err error)
+
+// A oneofMarshaler does the marshaling for all oneof fields in a message.
+type oneofMarshaler func(Message, *Buffer) error
+
+// A oneofUnmarshaler does the unmarshaling for a oneof field in a message.
+type oneofUnmarshaler func(Message, int, int, *Buffer) (bool, error)
+
+// A oneofSizer does the sizing for all oneof fields in a message.
+type oneofSizer func(Message) int
+
+// tagMap is an optimization over map[int]int for typical protocol buffer
+// use-cases. Encoded protocol buffers are often in tag order with small tag
+// numbers.
+type tagMap struct {
+	fastTags []int
+	slowTags map[int]int
+}
+
+// tagMapFastLimit is the upper bound on the tag number that will be stored in
+// the tagMap slice rather than its map.
+const tagMapFastLimit = 1024
+
+func (p *tagMap) get(t int) (int, bool) {
+	if t > 0 && t < tagMapFastLimit {
+		if t >= len(p.fastTags) {
+			return 0, false
+		}
+		fi := p.fastTags[t]
+		return fi, fi >= 0
+	}
+	fi, ok := p.slowTags[t]
+	return fi, ok
+}
+
+func (p *tagMap) put(t int, fi int) {
+	if t > 0 && t < tagMapFastLimit {
+		for len(p.fastTags) < t+1 {
+			p.fastTags = append(p.fastTags, -1)
+		}
+		p.fastTags[t] = fi
+		return
+	}
+	if p.slowTags == nil {
+		p.slowTags = make(map[int]int)
+	}
+	p.slowTags[t] = fi
+}
+
+// StructProperties represents properties for all the fields of a struct.
+// decoderTags and decoderOrigNames should only be used by the decoder.
+type StructProperties struct {
+	Prop             []*Properties  // properties for each field
+	reqCount         int            // required count
+	decoderTags      tagMap         // map from proto tag to struct field number
+	decoderOrigNames map[string]int // map from original name to struct field number
+	order            []int          // list of struct field numbers in tag order
+	unrecField       field          // field id of the XXX_unrecognized []byte field
+	extendable       bool           // is this an extendable proto
+
+	oneofMarshaler   oneofMarshaler
+	oneofUnmarshaler oneofUnmarshaler
+	oneofSizer       oneofSizer
+	stype            reflect.Type
+
+	// OneofTypes contains information about the oneof fields in this message.
+	// It is keyed by the original name of a field.
+	OneofTypes map[string]*OneofProperties
+}
+
+// OneofProperties represents information about a specific field in a oneof.
+type OneofProperties struct {
+	Type  reflect.Type // pointer to generated struct type for this oneof field
+	Field int          // struct field number of the containing oneof in the message
+	Prop  *Properties
+}
+
+// Implement the sorting interface so we can sort the fields in tag order, as recommended by the spec.
+// See encode.go, (*Buffer).enc_struct.
+
+func (sp *StructProperties) Len() int { return len(sp.order) }
+func (sp *StructProperties) Less(i, j int) bool {
+	return sp.Prop[sp.order[i]].Tag < sp.Prop[sp.order[j]].Tag
+}
+func (sp *StructProperties) Swap(i, j int) { sp.order[i], sp.order[j] = sp.order[j], sp.order[i] }
+
+// Properties represents the protocol-specific behavior of a single struct field.
+type Properties struct {
+	Name     string // name of the field, for error messages
+	OrigName string // original name before protocol compiler (always set)
+	JSONName string // name to use for JSON; determined by protoc
+	Wire     string
+	WireType int
+	Tag      int
+	Required bool
+	Optional bool
+	Repeated bool
+	Packed   bool   // relevant for repeated primitives only
+	Enum     string // set for enum types only
+	proto3   bool   // whether this is known to be a proto3 field; set for []byte only
+	oneof    bool   // whether this is a oneof field
+
+	Default    string // default value
+	HasDefault bool   // whether an explicit default was provided
+	def_uint64 uint64
+
+	enc           encoder
+	valEnc        valueEncoder // set for bool and numeric types only
+	field         field
+	tagcode       []byte // encoding of EncodeVarint((Tag<<3)|WireType)
+	tagbuf        [8]byte
+	stype         reflect.Type      // set for struct types only
+	sprop         *StructProperties // set for struct types only
+	isMarshaler   bool
+	isUnmarshaler bool
+
+	mtype    reflect.Type // set for map types only
+	mkeyprop *Properties  // set for map types only
+	mvalprop *Properties  // set for map types only
+
+	size    sizer
+	valSize valueSizer // set for bool and numeric types only
+
+	dec    decoder
+	valDec valueDecoder // set for bool and numeric types only
+
+	// If this is a packable field, this will be the decoder for the packed version of the field.
+	packedDec decoder
+}
+
+// String formats the properties in the protobuf struct field tag style.
+func (p *Properties) String() string {
+	s := p.Wire
+	s = ","
+	s += strconv.Itoa(p.Tag)
+	if p.Required {
+		s += ",req"
+	}
+	if p.Optional {
+		s += ",opt"
+	}
+	if p.Repeated {
+		s += ",rep"
+	}
+	if p.Packed {
+		s += ",packed"
+	}
+	s += ",name=" + p.OrigName
+	if p.JSONName != p.OrigName {
+		s += ",json=" + p.JSONName
+	}
+	if p.proto3 {
+		s += ",proto3"
+	}
+	if p.oneof {
+		s += ",oneof"
+	}
+	if len(p.Enum) > 0 {
+		s += ",enum=" + p.Enum
+	}
+	if p.HasDefault {
+		s += ",def=" + p.Default
+	}
+	return s
+}
+
+// Parse populates p by parsing a string in the protobuf struct field tag style.
+func (p *Properties) Parse(s string) {
+	// "bytes,49,opt,name=foo,def=hello!"
+	fields := strings.Split(s, ",") // breaks def=, but handled below.
+	if len(fields) < 2 {
+		fmt.Fprintf(os.Stderr, "proto: tag has too few fields: %q\n", s)
+		return
+	}
+
+	p.Wire = fields[0]
+	switch p.Wire {
+	case "varint":
+		p.WireType = WireVarint
+		p.valEnc = (*Buffer).EncodeVarint
+		p.valDec = (*Buffer).DecodeVarint
+		p.valSize = sizeVarint
+	case "fixed32":
+		p.WireType = WireFixed32
+		p.valEnc = (*Buffer).EncodeFixed32
+		p.valDec = (*Buffer).DecodeFixed32
+		p.valSize = sizeFixed32
+	case "fixed64":
+		p.WireType = WireFixed64
+		p.valEnc = (*Buffer).EncodeFixed64
+		p.valDec = (*Buffer).DecodeFixed64
+		p.valSize = sizeFixed64
+	case "zigzag32":
+		p.WireType = WireVarint
+		p.valEnc = (*Buffer).EncodeZigzag32
+		p.valDec = (*Buffer).DecodeZigzag32
+		p.valSize = sizeZigzag32
+	case "zigzag64":
+		p.WireType = WireVarint
+		p.valEnc = (*Buffer).EncodeZigzag64
+		p.valDec = (*Buffer).DecodeZigzag64
+		p.valSize = sizeZigzag64
+	case "bytes", "group":
+		p.WireType = WireBytes
+		// no numeric converter for non-numeric types
+	default:
+		fmt.Fprintf(os.Stderr, "proto: tag has unknown wire type: %q\n", s)
+		return
+	}
+
+	var err error
+	p.Tag, err = strconv.Atoi(fields[1])
+	if err != nil {
+		return
+	}
+
+	for i := 2; i < len(fields); i++ {
+		f := fields[i]
+		switch {
+		case f == "req":
+			p.Required = true
+		case f == "opt":
+			p.Optional = true
+		case f == "rep":
+			p.Repeated = true
+		case f == "packed":
+			p.Packed = true
+		case strings.HasPrefix(f, "name="):
+			p.OrigName = f[5:]
+		case strings.HasPrefix(f, "json="):
+			p.JSONName = f[5:]
+		case strings.HasPrefix(f, "enum="):
+			p.Enum = f[5:]
+		case f == "proto3":
+			p.proto3 = true
+		case f == "oneof":
+			p.oneof = true
+		case strings.HasPrefix(f, "def="):
+			p.HasDefault = true
+			p.Default = f[4:] // rest of string
+			if i+1 < len(fields) {
+				// Commas aren't escaped, and def is always last.
+				p.Default += "," + strings.Join(fields[i+1:], ",")
+				break
+			}
+		}
+	}
+}
+
+func logNoSliceEnc(t1, t2 reflect.Type) {
+	fmt.Fprintf(os.Stderr, "proto: no slice oenc for %T = []%T\n", t1, t2)
+}
+
+var protoMessageType = reflect.TypeOf((*Message)(nil)).Elem()
+
+// Initialize the fields for encoding and decoding.
+func (p *Properties) setEncAndDec(typ reflect.Type, f *reflect.StructField, lockGetProp bool) {
+	p.enc = nil
+	p.dec = nil
+	p.size = nil
+
+	switch t1 := typ; t1.Kind() {
+	default:
+		fmt.Fprintf(os.Stderr, "proto: no coders for %v\n", t1)
+
+	// proto3 scalar types
+
+	case reflect.Bool:
+		p.enc = (*Buffer).enc_proto3_bool
+		p.dec = (*Buffer).dec_proto3_bool
+		p.size = size_proto3_bool
+	case reflect.Int32:
+		p.enc = (*Buffer).enc_proto3_int32
+		p.dec = (*Buffer).dec_proto3_int32
+		p.size = size_proto3_int32
+	case reflect.Uint32:
+		p.enc = (*Buffer).enc_proto3_uint32
+		p.dec = (*Buffer).dec_proto3_int32 // can reuse
+		p.size = size_proto3_uint32
+	case reflect.Int64, reflect.Uint64:
+		p.enc = (*Buffer).enc_proto3_int64
+		p.dec = (*Buffer).dec_proto3_int64
+		p.size = size_proto3_int64
+	case reflect.Float32:
+		p.enc = (*Buffer).enc_proto3_uint32 // can just treat them as bits
+		p.dec = (*Buffer).dec_proto3_int32
+		p.size = size_proto3_uint32
+	case reflect.Float64:
+		p.enc = (*Buffer).enc_proto3_int64 // can just treat them as bits
+		p.dec = (*Buffer).dec_proto3_int64
+		p.size = size_proto3_int64
+	case reflect.String:
+		p.enc = (*Buffer).enc_proto3_string
+		p.dec = (*Buffer).dec_proto3_string
+		p.size = size_proto3_string
+
+	case reflect.Ptr:
+		switch t2 := t1.Elem(); t2.Kind() {
+		default:
+			fmt.Fprintf(os.Stderr, "proto: no encoder function for %v -> %v\n", t1, t2)
+			break
+		case reflect.Bool:
+			p.enc = (*Buffer).enc_bool
+			p.dec = (*Buffer).dec_bool
+			p.size = size_bool
+		case reflect.Int32:
+			p.enc = (*Buffer).enc_int32
+			p.dec = (*Buffer).dec_int32
+			p.size = size_int32
+		case reflect.Uint32:
+			p.enc = (*Buffer).enc_uint32
+			p.dec = (*Buffer).dec_int32 // can reuse
+			p.size = size_uint32
+		case reflect.Int64, reflect.Uint64:
+			p.enc = (*Buffer).enc_int64
+			p.dec = (*Buffer).dec_int64
+			p.size = size_int64
+		case reflect.Float32:
+			p.enc = (*Buffer).enc_uint32 // can just treat them as bits
+			p.dec = (*Buffer).dec_int32
+			p.size = size_uint32
+		case reflect.Float64:
+			p.enc = (*Buffer).enc_int64 // can just treat them as bits
+			p.dec = (*Buffer).dec_int64
+			p.size = size_int64
+		case reflect.String:
+			p.enc = (*Buffer).enc_string
+			p.dec = (*Buffer).dec_string
+			p.size = size_string
+		case reflect.Struct:
+			p.stype = t1.Elem()
+			p.isMarshaler = isMarshaler(t1)
+			p.isUnmarshaler = isUnmarshaler(t1)
+			if p.Wire == "bytes" {
+				p.enc = (*Buffer).enc_struct_message
+				p.dec = (*Buffer).dec_struct_message
+				p.size = size_struct_message
+			} else {
+				p.enc = (*Buffer).enc_struct_group
+				p.dec = (*Buffer).dec_struct_group
+				p.size = size_struct_group
+			}
+		}
+
+	case reflect.Slice:
+		switch t2 := t1.Elem(); t2.Kind() {
+		default:
+			logNoSliceEnc(t1, t2)
+			break
+		case reflect.Bool:
+			if p.Packed {
+				p.enc = (*Buffer).enc_slice_packed_bool
+				p.size = size_slice_packed_bool
+			} else {
+				p.enc = (*Buffer).enc_slice_bool
+				p.size = size_slice_bool
+			}
+			p.dec = (*Buffer).dec_slice_bool
+			p.packedDec = (*Buffer).dec_slice_packed_bool
+		case reflect.Int32:
+			if p.Packed {
+				p.enc = (*Buffer).enc_slice_packed_int32
+				p.size = size_slice_packed_int32
+			} else {
+				p.enc = (*Buffer).enc_slice_int32
+				p.size = size_slice_int32
+			}
+			p.dec = (*Buffer).dec_slice_int32
+			p.packedDec = (*Buffer).dec_slice_packed_int32
+		case reflect.Uint32:
+			if p.Packed {
+				p.enc = (*Buffer).enc_slice_packed_uint32
+				p.size = size_slice_packed_uint32
+			} else {
+				p.enc = (*Buffer).enc_slice_uint32
+				p.size = size_slice_uint32
+			}
+			p.dec = (*Buffer).dec_slice_int32
+			p.packedDec = (*Buffer).dec_slice_packed_int32
+		case reflect.Int64, reflect.Uint64:
+			if p.Packed {
+				p.enc = (*Buffer).enc_slice_packed_int64
+				p.size = size_slice_packed_int64
+			} else {
+				p.enc = (*Buffer).enc_slice_int64
+				p.size = size_slice_int64
+			}
+			p.dec = (*Buffer).dec_slice_int64
+			p.packedDec = (*Buffer).dec_slice_packed_int64
+		case reflect.Uint8:
+			p.dec = (*Buffer).dec_slice_byte
+			if p.proto3 {
+				p.enc = (*Buffer).enc_proto3_slice_byte
+				p.size = size_proto3_slice_byte
+			} else {
+				p.enc = (*Buffer).enc_slice_byte
+				p.size = size_slice_byte
+			}
+		case reflect.Float32, reflect.Float64:
+			switch t2.Bits() {
+			case 32:
+				// can just treat them as bits
+				if p.Packed {
+					p.enc = (*Buffer).enc_slice_packed_uint32
+					p.size = size_slice_packed_uint32
+				} else {
+					p.enc = (*Buffer).enc_slice_uint32
+					p.size = size_slice_uint32
+				}
+				p.dec = (*Buffer).dec_slice_int32
+				p.packedDec = (*Buffer).dec_slice_packed_int32
+			case 64:
+				// can just treat them as bits
+				if p.Packed {
+					p.enc = (*Buffer).enc_slice_packed_int64
+					p.size = size_slice_packed_int64
+				} else {
+					p.enc = (*Buffer).enc_slice_int64
+					p.size = size_slice_int64
+				}
+				p.dec = (*Buffer).dec_slice_int64
+				p.packedDec = (*Buffer).dec_slice_packed_int64
+			default:
+				logNoSliceEnc(t1, t2)
+				break
+			}
+		case reflect.String:
+			p.enc = (*Buffer).enc_slice_string
+			p.dec = (*Buffer).dec_slice_string
+			p.size = size_slice_string
+		case reflect.Ptr:
+			switch t3 := t2.Elem(); t3.Kind() {
+			default:
+				fmt.Fprintf(os.Stderr, "proto: no ptr oenc for %T -> %T -> %T\n", t1, t2, t3)
+				break
+			case reflect.Struct:
+				p.stype = t2.Elem()
+				p.isMarshaler = isMarshaler(t2)
+				p.isUnmarshaler = isUnmarshaler(t2)
+				if p.Wire == "bytes" {
+					p.enc = (*Buffer).enc_slice_struct_message
+					p.dec = (*Buffer).dec_slice_struct_message
+					p.size = size_slice_struct_message
+				} else {
+					p.enc = (*Buffer).enc_slice_struct_group
+					p.dec = (*Buffer).dec_slice_struct_group
+					p.size = size_slice_struct_group
+				}
+			}
+		case reflect.Slice:
+			switch t2.Elem().Kind() {
+			default:
+				fmt.Fprintf(os.Stderr, "proto: no slice elem oenc for %T -> %T -> %T\n", t1, t2, t2.Elem())
+				break
+			case reflect.Uint8:
+				p.enc = (*Buffer).enc_slice_slice_byte
+				p.dec = (*Buffer).dec_slice_slice_byte
+				p.size = size_slice_slice_byte
+			}
+		}
+
+	case reflect.Map:
+		p.enc = (*Buffer).enc_new_map
+		p.dec = (*Buffer).dec_new_map
+		p.size = size_new_map
+
+		p.mtype = t1
+		p.mkeyprop = &Properties{}
+		p.mkeyprop.init(reflect.PtrTo(p.mtype.Key()), "Key", f.Tag.Get("protobuf_key"), nil, lockGetProp)
+		p.mvalprop = &Properties{}
+		vtype := p.mtype.Elem()
+		if vtype.Kind() != reflect.Ptr && vtype.Kind() != reflect.Slice {
+			// The value type is not a message (*T) or bytes ([]byte),
+			// so we need encoders for the pointer to this type.
+			vtype = reflect.PtrTo(vtype)
+		}
+		p.mvalprop.init(vtype, "Value", f.Tag.Get("protobuf_val"), nil, lockGetProp)
+	}
+
+	// precalculate tag code
+	wire := p.WireType
+	if p.Packed {
+		wire = WireBytes
+	}
+	x := uint32(p.Tag)<<3 | uint32(wire)
+	i := 0
+	for i = 0; x > 127; i++ {
+		p.tagbuf[i] = 0x80 | uint8(x&0x7F)
+		x >>= 7
+	}
+	p.tagbuf[i] = uint8(x)
+	p.tagcode = p.tagbuf[0 : i+1]
+
+	if p.stype != nil {
+		if lockGetProp {
+			p.sprop = GetProperties(p.stype)
+		} else {
+			p.sprop = getPropertiesLocked(p.stype)
+		}
+	}
+}
+
+var (
+	marshalerType   = reflect.TypeOf((*Marshaler)(nil)).Elem()
+	unmarshalerType = reflect.TypeOf((*Unmarshaler)(nil)).Elem()
+)
+
+// isMarshaler reports whether type t implements Marshaler.
+func isMarshaler(t reflect.Type) bool {
+	// We're checking for (likely) pointer-receiver methods
+	// so if t is not a pointer, something is very wrong.
+	// The calls above only invoke isMarshaler on pointer types.
+	if t.Kind() != reflect.Ptr {
+		panic("proto: misuse of isMarshaler")
+	}
+	return t.Implements(marshalerType)
+}
+
+// isUnmarshaler reports whether type t implements Unmarshaler.
+func isUnmarshaler(t reflect.Type) bool {
+	// We're checking for (likely) pointer-receiver methods
+	// so if t is not a pointer, something is very wrong.
+	// The calls above only invoke isUnmarshaler on pointer types.
+	if t.Kind() != reflect.Ptr {
+		panic("proto: misuse of isUnmarshaler")
+	}
+	return t.Implements(unmarshalerType)
+}
+
+// Init populates the properties from a protocol buffer struct tag.
+func (p *Properties) Init(typ reflect.Type, name, tag string, f *reflect.StructField) {
+	p.init(typ, name, tag, f, true)
+}
+
+func (p *Properties) init(typ reflect.Type, name, tag string, f *reflect.StructField, lockGetProp bool) {
+	// "bytes,49,opt,def=hello!"
+	p.Name = name
+	p.OrigName = name
+	if f != nil {
+		p.field = toField(f)
+	}
+	if tag == "" {
+		return
+	}
+	p.Parse(tag)
+	p.setEncAndDec(typ, f, lockGetProp)
+}
+
+var (
+	propertiesMu  sync.RWMutex
+	propertiesMap = make(map[reflect.Type]*StructProperties)
+)
+
+// GetProperties returns the list of properties for the type represented by t.
+// t must represent a generated struct type of a protocol message.
+func GetProperties(t reflect.Type) *StructProperties {
+	if t.Kind() != reflect.Struct {
+		panic("proto: type must have kind struct")
+	}
+
+	// Most calls to GetProperties in a long-running program will be
+	// retrieving details for types we have seen before.
+	propertiesMu.RLock()
+	sprop, ok := propertiesMap[t]
+	propertiesMu.RUnlock()
+	if ok {
+		if collectStats {
+			stats.Chit++
+		}
+		return sprop
+	}
+
+	propertiesMu.Lock()
+	sprop = getPropertiesLocked(t)
+	propertiesMu.Unlock()
+	return sprop
+}
+
+// getPropertiesLocked requires that propertiesMu is held.
+func getPropertiesLocked(t reflect.Type) *StructProperties {
+	if prop, ok := propertiesMap[t]; ok {
+		if collectStats {
+			stats.Chit++
+		}
+		return prop
+	}
+	if collectStats {
+		stats.Cmiss++
+	}
+
+	prop := new(StructProperties)
+	// in case of recursive protos, fill this in now.
+	propertiesMap[t] = prop
+
+	// build properties
+	prop.extendable = reflect.PtrTo(t).Implements(extendableProtoType) ||
+		reflect.PtrTo(t).Implements(extendableProtoV1Type)
+	prop.unrecField = invalidField
+	prop.Prop = make([]*Properties, t.NumField())
+	prop.order = make([]int, t.NumField())
+
+	for i := 0; i < t.NumField(); i++ {
+		f := t.Field(i)
+		p := new(Properties)
+		name := f.Name
+		p.init(f.Type, name, f.Tag.Get("protobuf"), &f, false)
+
+		if f.Name == "XXX_InternalExtensions" { // special case
+			p.enc = (*Buffer).enc_exts
+			p.dec = nil // not needed
+			p.size = size_exts
+		} else if f.Name == "XXX_extensions" { // special case
+			p.enc = (*Buffer).enc_map
+			p.dec = nil // not needed
+			p.size = size_map
+		} else if f.Name == "XXX_unrecognized" { // special case
+			prop.unrecField = toField(&f)
+		}
+		oneof := f.Tag.Get("protobuf_oneof") // special case
+		if oneof != "" {
+			// Oneof fields don't use the traditional protobuf tag.
+			p.OrigName = oneof
+		}
+		prop.Prop[i] = p
+		prop.order[i] = i
+		if debug {
+			print(i, " ", f.Name, " ", t.String(), " ")
+			if p.Tag > 0 {
+				print(p.String())
+			}
+			print("\n")
+		}
+		if p.enc == nil && !strings.HasPrefix(f.Name, "XXX_") && oneof == "" {
+			fmt.Fprintln(os.Stderr, "proto: no encoder for", f.Name, f.Type.String(), "[GetProperties]")
+		}
+	}
+
+	// Re-order prop.order.
+	sort.Sort(prop)
+
+	type oneofMessage interface {
+		XXX_OneofFuncs() (func(Message, *Buffer) error, func(Message, int, int, *Buffer) (bool, error), func(Message) int, []interface{})
+	}
+	if om, ok := reflect.Zero(reflect.PtrTo(t)).Interface().(oneofMessage); ok {
+		var oots []interface{}
+		prop.oneofMarshaler, prop.oneofUnmarshaler, prop.oneofSizer, oots = om.XXX_OneofFuncs()
+		prop.stype = t
+
+		// Interpret oneof metadata.
+		prop.OneofTypes = make(map[string]*OneofProperties)
+		for _, oot := range oots {
+			oop := &OneofProperties{
+				Type: reflect.ValueOf(oot).Type(), // *T
+				Prop: new(Properties),
+			}
+			sft := oop.Type.Elem().Field(0)
+			oop.Prop.Name = sft.Name
+			oop.Prop.Parse(sft.Tag.Get("protobuf"))
+			// There will be exactly one interface field that
+			// this new value is assignable to.
+			for i := 0; i < t.NumField(); i++ {
+				f := t.Field(i)
+				if f.Type.Kind() != reflect.Interface {
+					continue
+				}
+				if !oop.Type.AssignableTo(f.Type) {
+					continue
+				}
+				oop.Field = i
+				break
+			}
+			prop.OneofTypes[oop.Prop.OrigName] = oop
+		}
+	}
+
+	// build required counts
+	// build tags
+	reqCount := 0
+	prop.decoderOrigNames = make(map[string]int)
+	for i, p := range prop.Prop {
+		if strings.HasPrefix(p.Name, "XXX_") {
+			// Internal fields should not appear in tags/origNames maps.
+			// They are handled specially when encoding and decoding.
+			continue
+		}
+		if p.Required {
+			reqCount++
+		}
+		prop.decoderTags.put(p.Tag, i)
+		prop.decoderOrigNames[p.OrigName] = i
+	}
+	prop.reqCount = reqCount
+
+	return prop
+}
+
+// Return the Properties object for the x[0]'th field of the structure.
+func propByIndex(t reflect.Type, x []int) *Properties {
+	if len(x) != 1 {
+		fmt.Fprintf(os.Stderr, "proto: field index dimension %d (not 1) for type %s\n", len(x), t)
+		return nil
+	}
+	prop := GetProperties(t)
+	return prop.Prop[x[0]]
+}
+
+// Get the address and type of a pointer to a struct from an interface.
+func getbase(pb Message) (t reflect.Type, b structPointer, err error) {
+	if pb == nil {
+		err = ErrNil
+		return
+	}
+	// get the reflect type of the pointer to the struct.
+	t = reflect.TypeOf(pb)
+	// get the address of the struct.
+	value := reflect.ValueOf(pb)
+	b = toStructPointer(value)
+	return
+}
+
+// A global registry of enum types.
+// The generated code will register the generated maps by calling RegisterEnum.
+
+var enumValueMaps = make(map[string]map[string]int32)
+
+// RegisterEnum is called from the generated code to install the enum descriptor
+// maps into the global table to aid parsing text format protocol buffers.
+func RegisterEnum(typeName string, unusedNameMap map[int32]string, valueMap map[string]int32) {
+	if _, ok := enumValueMaps[typeName]; ok {
+		panic("proto: duplicate enum registered: " + typeName)
+	}
+	enumValueMaps[typeName] = valueMap
+}
+
+// EnumValueMap returns the mapping from names to integers of the
+// enum type enumType, or a nil if not found.
+func EnumValueMap(enumType string) map[string]int32 {
+	return enumValueMaps[enumType]
+}
+
+// A registry of all linked message types.
+// The string is a fully-qualified proto name ("pkg.Message").
+var (
+	protoTypes    = make(map[string]reflect.Type)
+	revProtoTypes = make(map[reflect.Type]string)
+)
+
+// RegisterType is called from generated code and maps from the fully qualified
+// proto name to the type (pointer to struct) of the protocol buffer.
+func RegisterType(x Message, name string) {
+	if _, ok := protoTypes[name]; ok {
+		// TODO: Some day, make this a panic.
+		log.Printf("proto: duplicate proto type registered: %s", name)
+		return
+	}
+	t := reflect.TypeOf(x)
+	protoTypes[name] = t
+	revProtoTypes[t] = name
+}
+
+// MessageName returns the fully-qualified proto name for the given message type.
+func MessageName(x Message) string {
+	type xname interface {
+		XXX_MessageName() string
+	}
+	if m, ok := x.(xname); ok {
+		return m.XXX_MessageName()
+	}
+	return revProtoTypes[reflect.TypeOf(x)]
+}
+
+// MessageType returns the message type (pointer to struct) for a named message.
+func MessageType(name string) reflect.Type { return protoTypes[name] }
+
+// A registry of all linked proto files.
+var (
+	protoFiles = make(map[string][]byte) // file name => fileDescriptor
+)
+
+// RegisterFile is called from generated code and maps from the
+// full file name of a .proto file to its compressed FileDescriptorProto.
+func RegisterFile(filename string, fileDescriptor []byte) {
+	protoFiles[filename] = fileDescriptor
+}
+
+// FileDescriptor returns the compressed FileDescriptorProto for a .proto file.
+func FileDescriptor(filename string) []byte { return protoFiles[filename] }

vendor/github.com/golang/protobuf/proto/text.go

@@ -0,0 +1,854 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+// Functions for writing the text protocol buffer format.
+
+import (
+	"bufio"
+	"bytes"
+	"encoding"
+	"errors"
+	"fmt"
+	"io"
+	"log"
+	"math"
+	"reflect"
+	"sort"
+	"strings"
+)
+
+var (
+	newline         = []byte("\n")
+	spaces          = []byte("                                        ")
+	gtNewline       = []byte(">\n")
+	endBraceNewline = []byte("}\n")
+	backslashN      = []byte{'\\', 'n'}
+	backslashR      = []byte{'\\', 'r'}
+	backslashT      = []byte{'\\', 't'}
+	backslashDQ     = []byte{'\\', '"'}
+	backslashBS     = []byte{'\\', '\\'}
+	posInf          = []byte("inf")
+	negInf          = []byte("-inf")
+	nan             = []byte("nan")
+)
+
+type writer interface {
+	io.Writer
+	WriteByte(byte) error
+}
+
+// textWriter is an io.Writer that tracks its indentation level.
+type textWriter struct {
+	ind      int
+	complete bool // if the current position is a complete line
+	compact  bool // whether to write out as a one-liner
+	w        writer
+}
+
+func (w *textWriter) WriteString(s string) (n int, err error) {
+	if !strings.Contains(s, "\n") {
+		if !w.compact && w.complete {
+			w.writeIndent()
+		}
+		w.complete = false
+		return io.WriteString(w.w, s)
+	}
+	// WriteString is typically called without newlines, so this
+	// codepath and its copy are rare.  We copy to avoid
+	// duplicating all of Write's logic here.
+	return w.Write([]byte(s))
+}
+
+func (w *textWriter) Write(p []byte) (n int, err error) {
+	newlines := bytes.Count(p, newline)
+	if newlines == 0 {
+		if !w.compact && w.complete {
+			w.writeIndent()
+		}
+		n, err = w.w.Write(p)
+		w.complete = false
+		return n, err
+	}
+
+	frags := bytes.SplitN(p, newline, newlines+1)
+	if w.compact {
+		for i, frag := range frags {
+			if i > 0 {
+				if err := w.w.WriteByte(' '); err != nil {
+					return n, err
+				}
+				n++
+			}
+			nn, err := w.w.Write(frag)
+			n += nn
+			if err != nil {
+				return n, err
+			}
+		}
+		return n, nil
+	}
+
+	for i, frag := range frags {
+		if w.complete {
+			w.writeIndent()
+		}
+		nn, err := w.w.Write(frag)
+		n += nn
+		if err != nil {
+			return n, err
+		}
+		if i+1 < len(frags) {
+			if err := w.w.WriteByte('\n'); err != nil {
+				return n, err
+			}
+			n++
+		}
+	}
+	w.complete = len(frags[len(frags)-1]) == 0
+	return n, nil
+}
+
+func (w *textWriter) WriteByte(c byte) error {
+	if w.compact && c == '\n' {
+		c = ' '
+	}
+	if !w.compact && w.complete {
+		w.writeIndent()
+	}
+	err := w.w.WriteByte(c)
+	w.complete = c == '\n'
+	return err
+}
+
+func (w *textWriter) indent() { w.ind++ }
+
+func (w *textWriter) unindent() {
+	if w.ind == 0 {
+		log.Print("proto: textWriter unindented too far")
+		return
+	}
+	w.ind--
+}
+
+func writeName(w *textWriter, props *Properties) error {
+	if _, err := w.WriteString(props.OrigName); err != nil {
+		return err
+	}
+	if props.Wire != "group" {
+		return w.WriteByte(':')
+	}
+	return nil
+}
+
+// raw is the interface satisfied by RawMessage.
+type raw interface {
+	Bytes() []byte
+}
+
+func requiresQuotes(u string) bool {
+	// When type URL contains any characters except [0-9A-Za-z./\-]*, it must be quoted.
+	for _, ch := range u {
+		switch {
+		case ch == '.' || ch == '/' || ch == '_':
+			continue
+		case '0' <= ch && ch <= '9':
+			continue
+		case 'A' <= ch && ch <= 'Z':
+			continue
+		case 'a' <= ch && ch <= 'z':
+			continue
+		default:
+			return true
+		}
+	}
+	return false
+}
+
+// isAny reports whether sv is a google.protobuf.Any message
+func isAny(sv reflect.Value) bool {
+	type wkt interface {
+		XXX_WellKnownType() string
+	}
+	t, ok := sv.Addr().Interface().(wkt)
+	return ok && t.XXX_WellKnownType() == "Any"
+}
+
+// writeProto3Any writes an expanded google.protobuf.Any message.
+//
+// It returns (false, nil) if sv value can't be unmarshaled (e.g. because
+// required messages are not linked in).
+//
+// It returns (true, error) when sv was written in expanded format or an error
+// was encountered.
+func (tm *TextMarshaler) writeProto3Any(w *textWriter, sv reflect.Value) (bool, error) {
+	turl := sv.FieldByName("TypeUrl")
+	val := sv.FieldByName("Value")
+	if !turl.IsValid() || !val.IsValid() {
+		return true, errors.New("proto: invalid google.protobuf.Any message")
+	}
+
+	b, ok := val.Interface().([]byte)
+	if !ok {
+		return true, errors.New("proto: invalid google.protobuf.Any message")
+	}
+
+	parts := strings.Split(turl.String(), "/")
+	mt := MessageType(parts[len(parts)-1])
+	if mt == nil {
+		return false, nil
+	}
+	m := reflect.New(mt.Elem())
+	if err := Unmarshal(b, m.Interface().(Message)); err != nil {
+		return false, nil
+	}
+	w.Write([]byte("["))
+	u := turl.String()
+	if requiresQuotes(u) {
+		writeString(w, u)
+	} else {
+		w.Write([]byte(u))
+	}
+	if w.compact {
+		w.Write([]byte("]:<"))
+	} else {
+		w.Write([]byte("]: <\n"))
+		w.ind++
+	}
+	if err := tm.writeStruct(w, m.Elem()); err != nil {
+		return true, err
+	}
+	if w.compact {
+		w.Write([]byte("> "))
+	} else {
+		w.ind--
+		w.Write([]byte(">\n"))
+	}
+	return true, nil
+}
+
+func (tm *TextMarshaler) writeStruct(w *textWriter, sv reflect.Value) error {
+	if tm.ExpandAny && isAny(sv) {
+		if canExpand, err := tm.writeProto3Any(w, sv); canExpand {
+			return err
+		}
+	}
+	st := sv.Type()
+	sprops := GetProperties(st)
+	for i := 0; i < sv.NumField(); i++ {
+		fv := sv.Field(i)
+		props := sprops.Prop[i]
+		name := st.Field(i).Name
+
+		if strings.HasPrefix(name, "XXX_") {
+			// There are two XXX_ fields:
+			//   XXX_unrecognized []byte
+			//   XXX_extensions   map[int32]proto.Extension
+			// The first is handled here;
+			// the second is handled at the bottom of this function.
+			if name == "XXX_unrecognized" && !fv.IsNil() {
+				if err := writeUnknownStruct(w, fv.Interface().([]byte)); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+		if fv.Kind() == reflect.Ptr && fv.IsNil() {
+			// Field not filled in. This could be an optional field or
+			// a required field that wasn't filled in. Either way, there
+			// isn't anything we can show for it.
+			continue
+		}
+		if fv.Kind() == reflect.Slice && fv.IsNil() {
+			// Repeated field that is empty, or a bytes field that is unused.
+			continue
+		}
+
+		if props.Repeated && fv.Kind() == reflect.Slice {
+			// Repeated field.
+			for j := 0; j < fv.Len(); j++ {
+				if err := writeName(w, props); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte(' '); err != nil {
+						return err
+					}
+				}
+				v := fv.Index(j)
+				if v.Kind() == reflect.Ptr && v.IsNil() {
+					// A nil message in a repeated field is not valid,
+					// but we can handle that more gracefully than panicking.
+					if _, err := w.Write([]byte("<nil>\n")); err != nil {
+						return err
+					}
+					continue
+				}
+				if err := tm.writeAny(w, v, props); err != nil {
+					return err
+				}
+				if err := w.WriteByte('\n'); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+		if fv.Kind() == reflect.Map {
+			// Map fields are rendered as a repeated struct with key/value fields.
+			keys := fv.MapKeys()
+			sort.Sort(mapKeys(keys))
+			for _, key := range keys {
+				val := fv.MapIndex(key)
+				if err := writeName(w, props); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte(' '); err != nil {
+						return err
+					}
+				}
+				// open struct
+				if err := w.WriteByte('<'); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte('\n'); err != nil {
+						return err
+					}
+				}
+				w.indent()
+				// key
+				if _, err := w.WriteString("key:"); err != nil {
+					return err
+				}
+				if !w.compact {
+					if err := w.WriteByte(' '); err != nil {
+						return err
+					}
+				}
+				if err := tm.writeAny(w, key, props.mkeyprop); err != nil {
+					return err
+				}
+				if err := w.WriteByte('\n'); err != nil {
+					return err
+				}
+				// nil values aren't legal, but we can avoid panicking because of them.
+				if val.Kind() != reflect.Ptr || !val.IsNil() {
+					// value
+					if _, err := w.WriteString("value:"); err != nil {
+						return err
+					}
+					if !w.compact {
+						if err := w.WriteByte(' '); err != nil {
+							return err
+						}
+					}
+					if err := tm.writeAny(w, val, props.mvalprop); err != nil {
+						return err
+					}
+					if err := w.WriteByte('\n'); err != nil {
+						return err
+					}
+				}
+				// close struct
+				w.unindent()
+				if err := w.WriteByte('>'); err != nil {
+					return err
+				}
+				if err := w.WriteByte('\n'); err != nil {
+					return err
+				}
+			}
+			continue
+		}
+		if props.proto3 && fv.Kind() == reflect.Slice && fv.Len() == 0 {
+			// empty bytes field
+			continue
+		}
+		if fv.Kind() != reflect.Ptr && fv.Kind() != reflect.Slice {
+			// proto3 non-repeated scalar field; skip if zero value
+			if isProto3Zero(fv) {
+				continue
+			}
+		}
+
+		if fv.Kind() == reflect.Interface {
+			// Check if it is a oneof.
+			if st.Field(i).Tag.Get("protobuf_oneof") != "" {
+				// fv is nil, or holds a pointer to generated struct.
+				// That generated struct has exactly one field,
+				// which has a protobuf struct tag.
+				if fv.IsNil() {
+					continue
+				}
+				inner := fv.Elem().Elem() // interface -> *T -> T
+				tag := inner.Type().Field(0).Tag.Get("protobuf")
+				props = new(Properties) // Overwrite the outer props var, but not its pointee.
+				props.Parse(tag)
+				// Write the value in the oneof, not the oneof itself.
+				fv = inner.Field(0)
+
+				// Special case to cope with malformed messages gracefully:
+				// If the value in the oneof is a nil pointer, don't panic
+				// in writeAny.
+				if fv.Kind() == reflect.Ptr && fv.IsNil() {
+					// Use errors.New so writeAny won't render quotes.
+					msg := errors.New("/* nil */")
+					fv = reflect.ValueOf(&msg).Elem()
+				}
+			}
+		}
+
+		if err := writeName(w, props); err != nil {
+			return err
+		}
+		if !w.compact {
+			if err := w.WriteByte(' '); err != nil {
+				return err
+			}
+		}
+		if b, ok := fv.Interface().(raw); ok {
+			if err := writeRaw(w, b.Bytes()); err != nil {
+				return err
+			}
+			continue
+		}
+
+		// Enums have a String method, so writeAny will work fine.
+		if err := tm.writeAny(w, fv, props); err != nil {
+			return err
+		}
+
+		if err := w.WriteByte('\n'); err != nil {
+			return err
+		}
+	}
+
+	// Extensions (the XXX_extensions field).
+	pv := sv.Addr()
+	if _, ok := extendable(pv.Interface()); ok {
+		if err := tm.writeExtensions(w, pv); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+// writeRaw writes an uninterpreted raw message.
+func writeRaw(w *textWriter, b []byte) error {
+	if err := w.WriteByte('<'); err != nil {
+		return err
+	}
+	if !w.compact {
+		if err := w.WriteByte('\n'); err != nil {
+			return err
+		}
+	}
+	w.indent()
+	if err := writeUnknownStruct(w, b); err != nil {
+		return err
+	}
+	w.unindent()
+	if err := w.WriteByte('>'); err != nil {
+		return err
+	}
+	return nil
+}
+
+// writeAny writes an arbitrary field.
+func (tm *TextMarshaler) writeAny(w *textWriter, v reflect.Value, props *Properties) error {
+	v = reflect.Indirect(v)
+
+	// Floats have special cases.
+	if v.Kind() == reflect.Float32 || v.Kind() == reflect.Float64 {
+		x := v.Float()
+		var b []byte
+		switch {
+		case math.IsInf(x, 1):
+			b = posInf
+		case math.IsInf(x, -1):
+			b = negInf
+		case math.IsNaN(x):
+			b = nan
+		}
+		if b != nil {
+			_, err := w.Write(b)
+			return err
+		}
+		// Other values are handled below.
+	}
+
+	// We don't attempt to serialise every possible value type; only those
+	// that can occur in protocol buffers.
+	switch v.Kind() {
+	case reflect.Slice:
+		// Should only be a []byte; repeated fields are handled in writeStruct.
+		if err := writeString(w, string(v.Bytes())); err != nil {
+			return err
+		}
+	case reflect.String:
+		if err := writeString(w, v.String()); err != nil {
+			return err
+		}
+	case reflect.Struct:
+		// Required/optional group/message.
+		var bra, ket byte = '<', '>'
+		if props != nil && props.Wire == "group" {
+			bra, ket = '{', '}'
+		}
+		if err := w.WriteByte(bra); err != nil {
+			return err
+		}
+		if !w.compact {
+			if err := w.WriteByte('\n'); err != nil {
+				return err
+			}
+		}
+		w.indent()
+		if etm, ok := v.Interface().(encoding.TextMarshaler); ok {
+			text, err := etm.MarshalText()
+			if err != nil {
+				return err
+			}
+			if _, err = w.Write(text); err != nil {
+				return err
+			}
+		} else if err := tm.writeStruct(w, v); err != nil {
+			return err
+		}
+		w.unindent()
+		if err := w.WriteByte(ket); err != nil {
+			return err
+		}
+	default:
+		_, err := fmt.Fprint(w, v.Interface())
+		return err
+	}
+	return nil
+}
+
+// equivalent to C's isprint.
+func isprint(c byte) bool {
+	return c >= 0x20 && c < 0x7f
+}
+
+// writeString writes a string in the protocol buffer text format.
+// It is similar to strconv.Quote except we don't use Go escape sequences,
+// we treat the string as a byte sequence, and we use octal escapes.
+// These differences are to maintain interoperability with the other
+// languages' implementations of the text format.
+func writeString(w *textWriter, s string) error {
+	// use WriteByte here to get any needed indent
+	if err := w.WriteByte('"'); err != nil {
+		return err
+	}
+	// Loop over the bytes, not the runes.
+	for i := 0; i < len(s); i++ {
+		var err error
+		// Divergence from C++: we don't escape apostrophes.
+		// There's no need to escape them, and the C++ parser
+		// copes with a naked apostrophe.
+		switch c := s[i]; c {
+		case '\n':
+			_, err = w.w.Write(backslashN)
+		case '\r':
+			_, err = w.w.Write(backslashR)
+		case '\t':
+			_, err = w.w.Write(backslashT)
+		case '"':
+			_, err = w.w.Write(backslashDQ)
+		case '\\':
+			_, err = w.w.Write(backslashBS)
+		default:
+			if isprint(c) {
+				err = w.w.WriteByte(c)
+			} else {
+				_, err = fmt.Fprintf(w.w, "\\%03o", c)
+			}
+		}
+		if err != nil {
+			return err
+		}
+	}
+	return w.WriteByte('"')
+}
+
+func writeUnknownStruct(w *textWriter, data []byte) (err error) {
+	if !w.compact {
+		if _, err := fmt.Fprintf(w, "/* %d unknown bytes */\n", len(data)); err != nil {
+			return err
+		}
+	}
+	b := NewBuffer(data)
+	for b.index < len(b.buf) {
+		x, err := b.DecodeVarint()
+		if err != nil {
+			_, err := fmt.Fprintf(w, "/* %v */\n", err)
+			return err
+		}
+		wire, tag := x&7, x>>3
+		if wire == WireEndGroup {
+			w.unindent()
+			if _, err := w.Write(endBraceNewline); err != nil {
+				return err
+			}
+			continue
+		}
+		if _, err := fmt.Fprint(w, tag); err != nil {
+			return err
+		}
+		if wire != WireStartGroup {
+			if err := w.WriteByte(':'); err != nil {
+				return err
+			}
+		}
+		if !w.compact || wire == WireStartGroup {
+			if err := w.WriteByte(' '); err != nil {
+				return err
+			}
+		}
+		switch wire {
+		case WireBytes:
+			buf, e := b.DecodeRawBytes(false)
+			if e == nil {
+				_, err = fmt.Fprintf(w, "%q", buf)
+			} else {
+				_, err = fmt.Fprintf(w, "/* %v */", e)
+			}
+		case WireFixed32:
+			x, err = b.DecodeFixed32()
+			err = writeUnknownInt(w, x, err)
+		case WireFixed64:
+			x, err = b.DecodeFixed64()
+			err = writeUnknownInt(w, x, err)
+		case WireStartGroup:
+			err = w.WriteByte('{')
+			w.indent()
+		case WireVarint:
+			x, err = b.DecodeVarint()
+			err = writeUnknownInt(w, x, err)
+		default:
+			_, err = fmt.Fprintf(w, "/* unknown wire type %d */", wire)
+		}
+		if err != nil {
+			return err
+		}
+		if err = w.WriteByte('\n'); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func writeUnknownInt(w *textWriter, x uint64, err error) error {
+	if err == nil {
+		_, err = fmt.Fprint(w, x)
+	} else {
+		_, err = fmt.Fprintf(w, "/* %v */", err)
+	}
+	return err
+}
+
+type int32Slice []int32
+
+func (s int32Slice) Len() int           { return len(s) }
+func (s int32Slice) Less(i, j int) bool { return s[i] < s[j] }
+func (s int32Slice) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+
+// writeExtensions writes all the extensions in pv.
+// pv is assumed to be a pointer to a protocol message struct that is extendable.
+func (tm *TextMarshaler) writeExtensions(w *textWriter, pv reflect.Value) error {
+	emap := extensionMaps[pv.Type().Elem()]
+	ep, _ := extendable(pv.Interface())
+
+	// Order the extensions by ID.
+	// This isn't strictly necessary, but it will give us
+	// canonical output, which will also make testing easier.
+	m, mu := ep.extensionsRead()
+	if m == nil {
+		return nil
+	}
+	mu.Lock()
+	ids := make([]int32, 0, len(m))
+	for id := range m {
+		ids = append(ids, id)
+	}
+	sort.Sort(int32Slice(ids))
+	mu.Unlock()
+
+	for _, extNum := range ids {
+		ext := m[extNum]
+		var desc *ExtensionDesc
+		if emap != nil {
+			desc = emap[extNum]
+		}
+		if desc == nil {
+			// Unknown extension.
+			if err := writeUnknownStruct(w, ext.enc); err != nil {
+				return err
+			}
+			continue
+		}
+
+		pb, err := GetExtension(ep, desc)
+		if err != nil {
+			return fmt.Errorf("failed getting extension: %v", err)
+		}
+
+		// Repeated extensions will appear as a slice.
+		if !desc.repeated() {
+			if err := tm.writeExtension(w, desc.Name, pb); err != nil {
+				return err
+			}
+		} else {
+			v := reflect.ValueOf(pb)
+			for i := 0; i < v.Len(); i++ {
+				if err := tm.writeExtension(w, desc.Name, v.Index(i).Interface()); err != nil {
+					return err
+				}
+			}
+		}
+	}
+	return nil
+}
+
+func (tm *TextMarshaler) writeExtension(w *textWriter, name string, pb interface{}) error {
+	if _, err := fmt.Fprintf(w, "[%s]:", name); err != nil {
+		return err
+	}
+	if !w.compact {
+		if err := w.WriteByte(' '); err != nil {
+			return err
+		}
+	}
+	if err := tm.writeAny(w, reflect.ValueOf(pb), nil); err != nil {
+		return err
+	}
+	if err := w.WriteByte('\n'); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (w *textWriter) writeIndent() {
+	if !w.complete {
+		return
+	}
+	remain := w.ind * 2
+	for remain > 0 {
+		n := remain
+		if n > len(spaces) {
+			n = len(spaces)
+		}
+		w.w.Write(spaces[:n])
+		remain -= n
+	}
+	w.complete = false
+}
+
+// TextMarshaler is a configurable text format marshaler.
+type TextMarshaler struct {
+	Compact   bool // use compact text format (one line).
+	ExpandAny bool // expand google.protobuf.Any messages of known types
+}
+
+// Marshal writes a given protocol buffer in text format.
+// The only errors returned are from w.
+func (tm *TextMarshaler) Marshal(w io.Writer, pb Message) error {
+	val := reflect.ValueOf(pb)
+	if pb == nil || val.IsNil() {
+		w.Write([]byte("<nil>"))
+		return nil
+	}
+	var bw *bufio.Writer
+	ww, ok := w.(writer)
+	if !ok {
+		bw = bufio.NewWriter(w)
+		ww = bw
+	}
+	aw := &textWriter{
+		w:        ww,
+		complete: true,
+		compact:  tm.Compact,
+	}
+
+	if etm, ok := pb.(encoding.TextMarshaler); ok {
+		text, err := etm.MarshalText()
+		if err != nil {
+			return err
+		}
+		if _, err = aw.Write(text); err != nil {
+			return err
+		}
+		if bw != nil {
+			return bw.Flush()
+		}
+		return nil
+	}
+	// Dereference the received pointer so we don't have outer < and >.
+	v := reflect.Indirect(val)
+	if err := tm.writeStruct(aw, v); err != nil {
+		return err
+	}
+	if bw != nil {
+		return bw.Flush()
+	}
+	return nil
+}
+
+// Text is the same as Marshal, but returns the string directly.
+func (tm *TextMarshaler) Text(pb Message) string {
+	var buf bytes.Buffer
+	tm.Marshal(&buf, pb)
+	return buf.String()
+}
+
+var (
+	defaultTextMarshaler = TextMarshaler{}
+	compactTextMarshaler = TextMarshaler{Compact: true}
+)
+
+// TODO: consider removing some of the Marshal functions below.
+
+// MarshalText writes a given protocol buffer in text format.
+// The only errors returned are from w.
+func MarshalText(w io.Writer, pb Message) error { return defaultTextMarshaler.Marshal(w, pb) }
+
+// MarshalTextString is the same as MarshalText, but returns the string directly.
+func MarshalTextString(pb Message) string { return defaultTextMarshaler.Text(pb) }
+
+// CompactText writes a given protocol buffer in compact text format (one line).
+func CompactText(w io.Writer, pb Message) error { return compactTextMarshaler.Marshal(w, pb) }
+
+// CompactTextString is the same as CompactText, but returns the string directly.
+func CompactTextString(pb Message) string { return compactTextMarshaler.Text(pb) }

vendor/github.com/golang/protobuf/proto/text_parser.go

@@ -0,0 +1,895 @@
+// Go support for Protocol Buffers - Google's data interchange format
+//
+// Copyright 2010 The Go Authors.  All rights reserved.
+// https://github.com/golang/protobuf
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package proto
+
+// Functions for parsing the Text protocol buffer format.
+// TODO: message sets.
+
+import (
+	"encoding"
+	"errors"
+	"fmt"
+	"reflect"
+	"strconv"
+	"strings"
+	"unicode/utf8"
+)
+
+// Error string emitted when deserializing Any and fields are already set
+const anyRepeatedlyUnpacked = "Any message unpacked multiple times, or %q already set"
+
+type ParseError struct {
+	Message string
+	Line    int // 1-based line number
+	Offset  int // 0-based byte offset from start of input
+}
+
+func (p *ParseError) Error() string {
+	if p.Line == 1 {
+		// show offset only for first line
+		return fmt.Sprintf("line 1.%d: %v", p.Offset, p.Message)
+	}
+	return fmt.Sprintf("line %d: %v", p.Line, p.Message)
+}
+
+type token struct {
+	value    string
+	err      *ParseError
+	line     int    // line number
+	offset   int    // byte number from start of input, not start of line
+	unquoted string // the unquoted version of value, if it was a quoted string
+}
+
+func (t *token) String() string {
+	if t.err == nil {
+		return fmt.Sprintf("%q (line=%d, offset=%d)", t.value, t.line, t.offset)
+	}
+	return fmt.Sprintf("parse error: %v", t.err)
+}
+
+type textParser struct {
+	s            string // remaining input
+	done         bool   // whether the parsing is finished (success or error)
+	backed       bool   // whether back() was called
+	offset, line int
+	cur          token
+}
+
+func newTextParser(s string) *textParser {
+	p := new(textParser)
+	p.s = s
+	p.line = 1
+	p.cur.line = 1
+	return p
+}
+
+func (p *textParser) errorf(format string, a ...interface{}) *ParseError {
+	pe := &ParseError{fmt.Sprintf(format, a...), p.cur.line, p.cur.offset}
+	p.cur.err = pe
+	p.done = true
+	return pe
+}
+
+// Numbers and identifiers are matched by [-+._A-Za-z0-9]
+func isIdentOrNumberChar(c byte) bool {
+	switch {
+	case 'A' <= c && c <= 'Z', 'a' <= c && c <= 'z':
+		return true
+	case '0' <= c && c <= '9':
+		return true
+	}
+	switch c {
+	case '-', '+', '.', '_':
+		return true
+	}
+	return false
+}
+
+func isWhitespace(c byte) bool {
+	switch c {
+	case ' ', '\t', '\n', '\r':
+		return true
+	}
+	return false
+}
+
+func isQuote(c byte) bool {
+	switch c {
+	case '"', '\'':
+		return true
+	}
+	return false
+}
+
+func (p *textParser) skipWhitespace() {
+	i := 0
+	for i < len(p.s) && (isWhitespace(p.s[i]) || p.s[i] == '#') {
+		if p.s[i] == '#' {
+			// comment; skip to end of line or input
+			for i < len(p.s) && p.s[i] != '\n' {
+				i++
+			}
+			if i == len(p.s) {
+				break
+			}
+		}
+		if p.s[i] == '\n' {
+			p.line++
+		}
+		i++
+	}
+	p.offset += i
+	p.s = p.s[i:len(p.s)]
+	if len(p.s) == 0 {
+		p.done = true
+	}
+}
+
+func (p *textParser) advance() {
+	// Skip whitespace
+	p.skipWhitespace()
+	if p.done {
+		return
+	}
+
+	// Start of non-whitespace
+	p.cur.err = nil
+	p.cur.offset, p.cur.line = p.offset, p.line
+	p.cur.unquoted = ""
+	switch p.s[0] {
+	case '<', '>', '{', '}', ':', '[', ']', ';', ',', '/':
+		// Single symbol
+		p.cur.value, p.s = p.s[0:1], p.s[1:len(p.s)]
+	case '"', '\'':
+		// Quoted string
+		i := 1
+		for i < len(p.s) && p.s[i] != p.s[0] && p.s[i] != '\n' {
+			if p.s[i] == '\\' && i+1 < len(p.s) {
+				// skip escaped char
+				i++
+			}
+			i++
+		}
+		if i >= len(p.s) || p.s[i] != p.s[0] {
+			p.errorf("unmatched quote")
+			return
+		}
+		unq, err := unquoteC(p.s[1:i], rune(p.s[0]))
+		if err != nil {
+			p.errorf("invalid quoted string %s: %v", p.s[0:i+1], err)
+			return
+		}
+		p.cur.value, p.s = p.s[0:i+1], p.s[i+1:len(p.s)]
+		p.cur.unquoted = unq
+	default:
+		i := 0
+		for i < len(p.s) && isIdentOrNumberChar(p.s[i]) {
+			i++
+		}
+		if i == 0 {
+			p.errorf("unexpected byte %#x", p.s[0])
+			return
+		}
+		p.cur.value, p.s = p.s[0:i], p.s[i:len(p.s)]
+	}
+	p.offset += len(p.cur.value)
+}
+
+var (
+	errBadUTF8 = errors.New("proto: bad UTF-8")
+	errBadHex  = errors.New("proto: bad hexadecimal")
+)
+
+func unquoteC(s string, quote rune) (string, error) {
+	// This is based on C++'s tokenizer.cc.
+	// Despite its name, this is *not* parsing C syntax.
+	// For instance, "\0" is an invalid quoted string.
+
+	// Avoid allocation in trivial cases.
+	simple := true
+	for _, r := range s {
+		if r == '\\' || r == quote {
+			simple = false
+			break
+		}
+	}
+	if simple {
+		return s, nil
+	}
+
+	buf := make([]byte, 0, 3*len(s)/2)
+	for len(s) > 0 {
+		r, n := utf8.DecodeRuneInString(s)
+		if r == utf8.RuneError && n == 1 {
+			return "", errBadUTF8
+		}
+		s = s[n:]
+		if r != '\\' {
+			if r < utf8.RuneSelf {
+				buf = append(buf, byte(r))
+			} else {
+				buf = append(buf, string(r)...)
+			}
+			continue
+		}
+
+		ch, tail, err := unescape(s)
+		if err != nil {
+			return "", err
+		}
+		buf = append(buf, ch...)
+		s = tail
+	}
+	return string(buf), nil
+}
+
+func unescape(s string) (ch string, tail string, err error) {
+	r, n := utf8.DecodeRuneInString(s)
+	if r == utf8.RuneError && n == 1 {
+		return "", "", errBadUTF8
+	}
+	s = s[n:]
+	switch r {
+	case 'a':
+		return "\a", s, nil
+	case 'b':
+		return "\b", s, nil
+	case 'f':
+		return "\f", s, nil
+	case 'n':
+		return "\n", s, nil
+	case 'r':
+		return "\r", s, nil
+	case 't':
+		return "\t", s, nil
+	case 'v':
+		return "\v", s, nil
+	case '?':
+		return "?", s, nil // trigraph workaround
+	case '\'', '"', '\\':
+		return string(r), s, nil
+	case '0', '1', '2', '3', '4', '5', '6', '7', 'x', 'X':
+		if len(s) < 2 {
+			return "", "", fmt.Errorf(`\%c requires 2 following digits`, r)
+		}
+		base := 8
+		ss := s[:2]
+		s = s[2:]
+		if r == 'x' || r == 'X' {
+			base = 16
+		} else {
+			ss = string(r) + ss
+		}
+		i, err := strconv.ParseUint(ss, base, 8)
+		if err != nil {
+			return "", "", err
+		}
+		return string([]byte{byte(i)}), s, nil
+	case 'u', 'U':
+		n := 4
+		if r == 'U' {
+			n = 8
+		}
+		if len(s) < n {
+			return "", "", fmt.Errorf(`\%c requires %d digits`, r, n)
+		}
+
+		bs := make([]byte, n/2)
+		for i := 0; i < n; i += 2 {
+			a, ok1 := unhex(s[i])
+			b, ok2 := unhex(s[i+1])
+			if !ok1 || !ok2 {
+				return "", "", errBadHex
+			}
+			bs[i/2] = a<<4 | b
+		}
+		s = s[n:]
+		return string(bs), s, nil
+	}
+	return "", "", fmt.Errorf(`unknown escape \%c`, r)
+}
+
+// Adapted from src/pkg/strconv/quote.go.
+func unhex(b byte) (v byte, ok bool) {
+	switch {
+	case '0' <= b && b <= '9':
+		return b - '0', true
+	case 'a' <= b && b <= 'f':
+		return b - 'a' + 10, true
+	case 'A' <= b && b <= 'F':
+		return b - 'A' + 10, true
+	}
+	return 0, false
+}
+
+// Back off the parser by one token. Can only be done between calls to next().
+// It makes the next advance() a no-op.
+func (p *textParser) back() { p.backed = true }
+
+// Advances the parser and returns the new current token.
+func (p *textParser) next() *token {
+	if p.backed || p.done {
+		p.backed = false
+		return &p.cur
+	}
+	p.advance()
+	if p.done {
+		p.cur.value = ""
+	} else if len(p.cur.value) > 0 && isQuote(p.cur.value[0]) {
+		// Look for multiple quoted strings separated by whitespace,
+		// and concatenate them.
+		cat := p.cur
+		for {
+			p.skipWhitespace()
+			if p.done || !isQuote(p.s[0]) {
+				break
+			}
+			p.advance()
+			if p.cur.err != nil {
+				return &p.cur
+			}
+			cat.value += " " + p.cur.value
+			cat.unquoted += p.cur.unquoted
+		}
+		p.done = false // parser may have seen EOF, but we want to return cat
+		p.cur = cat
+	}
+	return &p.cur
+}
+
+func (p *textParser) consumeToken(s string) error {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value != s {
+		p.back()
+		return p.errorf("expected %q, found %q", s, tok.value)
+	}
+	return nil
+}
+
+// Return a RequiredNotSetError indicating which required field was not set.
+func (p *textParser) missingRequiredFieldError(sv reflect.Value) *RequiredNotSetError {
+	st := sv.Type()
+	sprops := GetProperties(st)
+	for i := 0; i < st.NumField(); i++ {
+		if !isNil(sv.Field(i)) {
+			continue
+		}
+
+		props := sprops.Prop[i]
+		if props.Required {
+			return &RequiredNotSetError{fmt.Sprintf("%v.%v", st, props.OrigName)}
+		}
+	}
+	return &RequiredNotSetError{fmt.Sprintf("%v.<unknown field name>", st)} // should not happen
+}
+
+// Returns the index in the struct for the named field, as well as the parsed tag properties.
+func structFieldByName(sprops *StructProperties, name string) (int, *Properties, bool) {
+	i, ok := sprops.decoderOrigNames[name]
+	if ok {
+		return i, sprops.Prop[i], true
+	}
+	return -1, nil, false
+}
+
+// Consume a ':' from the input stream (if the next token is a colon),
+// returning an error if a colon is needed but not present.
+func (p *textParser) checkForColon(props *Properties, typ reflect.Type) *ParseError {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value != ":" {
+		// Colon is optional when the field is a group or message.
+		needColon := true
+		switch props.Wire {
+		case "group":
+			needColon = false
+		case "bytes":
+			// A "bytes" field is either a message, a string, or a repeated field;
+			// those three become *T, *string and []T respectively, so we can check for
+			// this field being a pointer to a non-string.
+			if typ.Kind() == reflect.Ptr {
+				// *T or *string
+				if typ.Elem().Kind() == reflect.String {
+					break
+				}
+			} else if typ.Kind() == reflect.Slice {
+				// []T or []*T
+				if typ.Elem().Kind() != reflect.Ptr {
+					break
+				}
+			} else if typ.Kind() == reflect.String {
+				// The proto3 exception is for a string field,
+				// which requires a colon.
+				break
+			}
+			needColon = false
+		}
+		if needColon {
+			return p.errorf("expected ':', found %q", tok.value)
+		}
+		p.back()
+	}
+	return nil
+}
+
+func (p *textParser) readStruct(sv reflect.Value, terminator string) error {
+	st := sv.Type()
+	sprops := GetProperties(st)
+	reqCount := sprops.reqCount
+	var reqFieldErr error
+	fieldSet := make(map[string]bool)
+	// A struct is a sequence of "name: value", terminated by one of
+	// '>' or '}', or the end of the input.  A name may also be
+	// "[extension]" or "[type/url]".
+	//
+	// The whole struct can also be an expanded Any message, like:
+	// [type/url] < ... struct contents ... >
+	for {
+		tok := p.next()
+		if tok.err != nil {
+			return tok.err
+		}
+		if tok.value == terminator {
+			break
+		}
+		if tok.value == "[" {
+			// Looks like an extension or an Any.
+			//
+			// TODO: Check whether we need to handle
+			// namespace rooted names (e.g. ".something.Foo").
+			extName, err := p.consumeExtName()
+			if err != nil {
+				return err
+			}
+
+			if s := strings.LastIndex(extName, "/"); s >= 0 {
+				// If it contains a slash, it's an Any type URL.
+				messageName := extName[s+1:]
+				mt := MessageType(messageName)
+				if mt == nil {
+					return p.errorf("unrecognized message %q in google.protobuf.Any", messageName)
+				}
+				tok = p.next()
+				if tok.err != nil {
+					return tok.err
+				}
+				// consume an optional colon
+				if tok.value == ":" {
+					tok = p.next()
+					if tok.err != nil {
+						return tok.err
+					}
+				}
+				var terminator string
+				switch tok.value {
+				case "<":
+					terminator = ">"
+				case "{":
+					terminator = "}"
+				default:
+					return p.errorf("expected '{' or '<', found %q", tok.value)
+				}
+				v := reflect.New(mt.Elem())
+				if pe := p.readStruct(v.Elem(), terminator); pe != nil {
+					return pe
+				}
+				b, err := Marshal(v.Interface().(Message))
+				if err != nil {
+					return p.errorf("failed to marshal message of type %q: %v", messageName, err)
+				}
+				if fieldSet["type_url"] {
+					return p.errorf(anyRepeatedlyUnpacked, "type_url")
+				}
+				if fieldSet["value"] {
+					return p.errorf(anyRepeatedlyUnpacked, "value")
+				}
+				sv.FieldByName("TypeUrl").SetString(extName)
+				sv.FieldByName("Value").SetBytes(b)
+				fieldSet["type_url"] = true
+				fieldSet["value"] = true
+				continue
+			}
+
+			var desc *ExtensionDesc
+			// This could be faster, but it's functional.
+			// TODO: Do something smarter than a linear scan.
+			for _, d := range RegisteredExtensions(reflect.New(st).Interface().(Message)) {
+				if d.Name == extName {
+					desc = d
+					break
+				}
+			}
+			if desc == nil {
+				return p.errorf("unrecognized extension %q", extName)
+			}
+
+			props := &Properties{}
+			props.Parse(desc.Tag)
+
+			typ := reflect.TypeOf(desc.ExtensionType)
+			if err := p.checkForColon(props, typ); err != nil {
+				return err
+			}
+
+			rep := desc.repeated()
+
+			// Read the extension structure, and set it in
+			// the value we're constructing.
+			var ext reflect.Value
+			if !rep {
+				ext = reflect.New(typ).Elem()
+			} else {
+				ext = reflect.New(typ.Elem()).Elem()
+			}
+			if err := p.readAny(ext, props); err != nil {
+				if _, ok := err.(*RequiredNotSetError); !ok {
+					return err
+				}
+				reqFieldErr = err
+			}
+			ep := sv.Addr().Interface().(Message)
+			if !rep {
+				SetExtension(ep, desc, ext.Interface())
+			} else {
+				old, err := GetExtension(ep, desc)
+				var sl reflect.Value
+				if err == nil {
+					sl = reflect.ValueOf(old) // existing slice
+				} else {
+					sl = reflect.MakeSlice(typ, 0, 1)
+				}
+				sl = reflect.Append(sl, ext)
+				SetExtension(ep, desc, sl.Interface())
+			}
+			if err := p.consumeOptionalSeparator(); err != nil {
+				return err
+			}
+			continue
+		}
+
+		// This is a normal, non-extension field.
+		name := tok.value
+		var dst reflect.Value
+		fi, props, ok := structFieldByName(sprops, name)
+		if ok {
+			dst = sv.Field(fi)
+		} else if oop, ok := sprops.OneofTypes[name]; ok {
+			// It is a oneof.
+			props = oop.Prop
+			nv := reflect.New(oop.Type.Elem())
+			dst = nv.Elem().Field(0)
+			field := sv.Field(oop.Field)
+			if !field.IsNil() {
+				return p.errorf("field '%s' would overwrite already parsed oneof '%s'", name, sv.Type().Field(oop.Field).Name)
+			}
+			field.Set(nv)
+		}
+		if !dst.IsValid() {
+			return p.errorf("unknown field name %q in %v", name, st)
+		}
+
+		if dst.Kind() == reflect.Map {
+			// Consume any colon.
+			if err := p.checkForColon(props, dst.Type()); err != nil {
+				return err
+			}
+
+			// Construct the map if it doesn't already exist.
+			if dst.IsNil() {
+				dst.Set(reflect.MakeMap(dst.Type()))
+			}
+			key := reflect.New(dst.Type().Key()).Elem()
+			val := reflect.New(dst.Type().Elem()).Elem()
+
+			// The map entry should be this sequence of tokens:
+			//	< key : KEY value : VALUE >
+			// However, implementations may omit key or value, and technically
+			// we should support them in any order.  See b/28924776 for a time
+			// this went wrong.
+
+			tok := p.next()
+			var terminator string
+			switch tok.value {
+			case "<":
+				terminator = ">"
+			case "{":
+				terminator = "}"
+			default:
+				return p.errorf("expected '{' or '<', found %q", tok.value)
+			}
+			for {
+				tok := p.next()
+				if tok.err != nil {
+					return tok.err
+				}
+				if tok.value == terminator {
+					break
+				}
+				switch tok.value {
+				case "key":
+					if err := p.consumeToken(":"); err != nil {
+						return err
+					}
+					if err := p.readAny(key, props.mkeyprop); err != nil {
+						return err
+					}
+					if err := p.consumeOptionalSeparator(); err != nil {
+						return err
+					}
+				case "value":
+					if err := p.checkForColon(props.mvalprop, dst.Type().Elem()); err != nil {
+						return err
+					}
+					if err := p.readAny(val, props.mvalprop); err != nil {
+						return err
+					}
+					if err := p.consumeOptionalSeparator(); err != nil {
+						return err
+					}
+				default:
+					p.back()
+					return p.errorf(`expected "key", "value", or %q, found %q`, terminator, tok.value)
+				}
+			}
+
+			dst.SetMapIndex(key, val)
+			continue
+		}
+
+		// Check that it's not already set if it's not a repeated field.
+		if !props.Repeated && fieldSet[name] {
+			return p.errorf("non-repeated field %q was repeated", name)
+		}
+
+		if err := p.checkForColon(props, dst.Type()); err != nil {
+			return err
+		}
+
+		// Parse into the field.
+		fieldSet[name] = true
+		if err := p.readAny(dst, props); err != nil {
+			if _, ok := err.(*RequiredNotSetError); !ok {
+				return err
+			}
+			reqFieldErr = err
+		}
+		if props.Required {
+			reqCount--
+		}
+
+		if err := p.consumeOptionalSeparator(); err != nil {
+			return err
+		}
+
+	}
+
+	if reqCount > 0 {
+		return p.missingRequiredFieldError(sv)
+	}
+	return reqFieldErr
+}
+
+// consumeExtName consumes extension name or expanded Any type URL and the
+// following ']'. It returns the name or URL consumed.
+func (p *textParser) consumeExtName() (string, error) {
+	tok := p.next()
+	if tok.err != nil {
+		return "", tok.err
+	}
+
+	// If extension name or type url is quoted, it's a single token.
+	if len(tok.value) > 2 && isQuote(tok.value[0]) && tok.value[len(tok.value)-1] == tok.value[0] {
+		name, err := unquoteC(tok.value[1:len(tok.value)-1], rune(tok.value[0]))
+		if err != nil {
+			return "", err
+		}
+		return name, p.consumeToken("]")
+	}
+
+	// Consume everything up to "]"
+	var parts []string
+	for tok.value != "]" {
+		parts = append(parts, tok.value)
+		tok = p.next()
+		if tok.err != nil {
+			return "", p.errorf("unrecognized type_url or extension name: %s", tok.err)
+		}
+	}
+	return strings.Join(parts, ""), nil
+}
+
+// consumeOptionalSeparator consumes an optional semicolon or comma.
+// It is used in readStruct to provide backward compatibility.
+func (p *textParser) consumeOptionalSeparator() error {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value != ";" && tok.value != "," {
+		p.back()
+	}
+	return nil
+}
+
+func (p *textParser) readAny(v reflect.Value, props *Properties) error {
+	tok := p.next()
+	if tok.err != nil {
+		return tok.err
+	}
+	if tok.value == "" {
+		return p.errorf("unexpected EOF")
+	}
+
+	switch fv := v; fv.Kind() {
+	case reflect.Slice:
+		at := v.Type()
+		if at.Elem().Kind() == reflect.Uint8 {
+			// Special case for []byte
+			if tok.value[0] != '"' && tok.value[0] != '\'' {
+				// Deliberately written out here, as the error after
+				// this switch statement would write "invalid []byte: ...",
+				// which is not as user-friendly.
+				return p.errorf("invalid string: %v", tok.value)
+			}
+			bytes := []byte(tok.unquoted)
+			fv.Set(reflect.ValueOf(bytes))
+			return nil
+		}
+		// Repeated field.
+		if tok.value == "[" {
+			// Repeated field with list notation, like [1,2,3].
+			for {
+				fv.Set(reflect.Append(fv, reflect.New(at.Elem()).Elem()))
+				err := p.readAny(fv.Index(fv.Len()-1), props)
+				if err != nil {
+					return err
+				}
+				tok := p.next()
+				if tok.err != nil {
+					return tok.err
+				}
+				if tok.value == "]" {
+					break
+				}
+				if tok.value != "," {
+					return p.errorf("Expected ']' or ',' found %q", tok.value)
+				}
+			}
+			return nil
+		}
+		// One value of the repeated field.
+		p.back()
+		fv.Set(reflect.Append(fv, reflect.New(at.Elem()).Elem()))
+		return p.readAny(fv.Index(fv.Len()-1), props)
+	case reflect.Bool:
+		// true/1/t/True or false/f/0/False.
+		switch tok.value {
+		case "true", "1", "t", "True":
+			fv.SetBool(true)
+			return nil
+		case "false", "0", "f", "False":
+			fv.SetBool(false)
+			return nil
+		}
+	case reflect.Float32, reflect.Float64:
+		v := tok.value
+		// Ignore 'f' for compatibility with output generated by C++, but don't
+		// remove 'f' when the value is "-inf" or "inf".
+		if strings.HasSuffix(v, "f") && tok.value != "-inf" && tok.value != "inf" {
+			v = v[:len(v)-1]
+		}
+		if f, err := strconv.ParseFloat(v, fv.Type().Bits()); err == nil {
+			fv.SetFloat(f)
+			return nil
+		}
+	case reflect.Int32:
+		if x, err := strconv.ParseInt(tok.value, 0, 32); err == nil {
+			fv.SetInt(x)
+			return nil
+		}
+
+		if len(props.Enum) == 0 {
+			break
+		}
+		m, ok := enumValueMaps[props.Enum]
+		if !ok {
+			break
+		}
+		x, ok := m[tok.value]
+		if !ok {
+			break
+		}
+		fv.SetInt(int64(x))
+		return nil
+	case reflect.Int64:
+		if x, err := strconv.ParseInt(tok.value, 0, 64); err == nil {
+			fv.SetInt(x)
+			return nil
+		}
+
+	case reflect.Ptr:
+		// A basic field (indirected through pointer), or a repeated message/group
+		p.back()
+		fv.Set(reflect.New(fv.Type().Elem()))
+		return p.readAny(fv.Elem(), props)
+	case reflect.String:
+		if tok.value[0] == '"' || tok.value[0] == '\'' {
+			fv.SetString(tok.unquoted)
+			return nil
+		}
+	case reflect.Struct:
+		var terminator string
+		switch tok.value {
+		case "{":
+			terminator = "}"
+		case "<":
+			terminator = ">"
+		default:
+			return p.errorf("expected '{' or '<', found %q", tok.value)
+		}
+		// TODO: Handle nested messages which implement encoding.TextUnmarshaler.
+		return p.readStruct(fv, terminator)
+	case reflect.Uint32:
+		if x, err := strconv.ParseUint(tok.value, 0, 32); err == nil {
+			fv.SetUint(x)
+			return nil
+		}
+	case reflect.Uint64:
+		if x, err := strconv.ParseUint(tok.value, 0, 64); err == nil {
+			fv.SetUint(x)
+			return nil
+		}
+	}
+	return p.errorf("invalid %v: %v", v.Type(), tok.value)
+}
+
+// UnmarshalText reads a protocol buffer in Text format. UnmarshalText resets pb
+// before starting to unmarshal, so any existing data in pb is always removed.
+// If a required field is not set and no other error occurs,
+// UnmarshalText returns *RequiredNotSetError.
+func UnmarshalText(s string, pb Message) error {
+	if um, ok := pb.(encoding.TextUnmarshaler); ok {
+		err := um.UnmarshalText([]byte(s))
+		return err
+	}
+	pb.Reset()
+	v := reflect.ValueOf(pb)
+	if pe := newTextParser(s).readStruct(v.Elem(), ""); pe != nil {
+		return pe
+	}
+	return nil
+}

vendor/github.com/matttproud/golang_protobuf_extensions/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "{}"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright {yyyy} {name of copyright owner}
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/matttproud/golang_protobuf_extensions/NOTICE

@@ -0,0 +1 @@
+Copyright 2012 Matt T. Proud ([email protected])

vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/decode.go

@@ -0,0 +1,75 @@
+// Copyright 2013 Matt T. Proud
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pbutil
+
+import (
+	"encoding/binary"
+	"errors"
+	"io"
+
+	"github.com/golang/protobuf/proto"
+)
+
+var errInvalidVarint = errors.New("invalid varint32 encountered")
+
+// ReadDelimited decodes a message from the provided length-delimited stream,
+// where the length is encoded as 32-bit varint prefix to the message body.
+// It returns the total number of bytes read and any applicable error.  This is
+// roughly equivalent to the companion Java API's
+// MessageLite#parseDelimitedFrom.  As per the reader contract, this function
+// calls r.Read repeatedly as required until exactly one message including its
+// prefix is read and decoded (or an error has occurred).  The function never
+// reads more bytes from the stream than required.  The function never returns
+// an error if a message has been read and decoded correctly, even if the end
+// of the stream has been reached in doing so.  In that case, any subsequent
+// calls return (0, io.EOF).
+func ReadDelimited(r io.Reader, m proto.Message) (n int, err error) {
+	// Per AbstractParser#parsePartialDelimitedFrom with
+	// CodedInputStream#readRawVarint32.
+	var headerBuf [binary.MaxVarintLen32]byte
+	var bytesRead, varIntBytes int
+	var messageLength uint64
+	for varIntBytes == 0 { // i.e. no varint has been decoded yet.
+		if bytesRead >= len(headerBuf) {
+			return bytesRead, errInvalidVarint
+		}
+		// We have to read byte by byte here to avoid reading more bytes
+		// than required. Each read byte is appended to what we have
+		// read before.
+		newBytesRead, err := r.Read(headerBuf[bytesRead : bytesRead+1])
+		if newBytesRead == 0 {
+			if err != nil {
+				return bytesRead, err
+			}
+			// A Reader should not return (0, nil), but if it does,
+			// it should be treated as no-op (according to the
+			// Reader contract). So let's go on...
+			continue
+		}
+		bytesRead += newBytesRead
+		// Now present everything read so far to the varint decoder and
+		// see if a varint can be decoded already.
+		messageLength, varIntBytes = proto.DecodeVarint(headerBuf[:bytesRead])
+	}
+
+	messageBuf := make([]byte, messageLength)
+	newBytesRead, err := io.ReadFull(r, messageBuf)
+	bytesRead += newBytesRead
+	if err != nil {
+		return bytesRead, err
+	}
+
+	return bytesRead, proto.Unmarshal(messageBuf, m)
+}

vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/doc.go

@@ -0,0 +1,16 @@
+// Copyright 2013 Matt T. Proud
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package pbutil provides record length-delimited Protocol Buffer streaming.
+package pbutil

vendor/github.com/matttproud/golang_protobuf_extensions/pbutil/encode.go

@@ -0,0 +1,46 @@
+// Copyright 2013 Matt T. Proud
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pbutil
+
+import (
+	"encoding/binary"
+	"io"
+
+	"github.com/golang/protobuf/proto"
+)
+
+// WriteDelimited encodes and dumps a message to the provided writer prefixed
+// with a 32-bit varint indicating the length of the encoded message, producing
+// a length-delimited record stream, which can be used to chain together
+// encoded messages of the same type together in a file.  It returns the total
+// number of bytes written and any applicable error.  This is roughly
+// equivalent to the companion Java API's MessageLite#writeDelimitedTo.
+func WriteDelimited(w io.Writer, m proto.Message) (n int, err error) {
+	buffer, err := proto.Marshal(m)
+	if err != nil {
+		return 0, err
+	}
+
+	var buf [binary.MaxVarintLen32]byte
+	encodedLength := binary.PutUvarint(buf[:], uint64(len(buffer)))
+
+	sync, err := w.Write(buf[:encodedLength])
+	if err != nil {
+		return sync, err
+	}
+
+	n, err = w.Write(buffer)
+	return n + sync, err
+}

vendor/github.com/prometheus/client_golang/AUTHORS.md

@@ -0,0 +1,18 @@
+The Prometheus project was started by Matt T. Proud (emeritus) and
+Julius Volz in 2012.
+
+Maintainers of this repository:
+
+* Björn Rabenstein <[email protected]>
+
+The following individuals have contributed code to this repository
+(listed in alphabetical order):
+
+* Bernerd Schaefer <[email protected]>
+* Björn Rabenstein <[email protected]>
+* Daniel Bornkessel <[email protected]>
+* Jeff Younker <[email protected]>
+* Julius Volz <[email protected]>
+* Matt T. Proud <[email protected]>
+* Tobias Schmidt <[email protected]>
+

vendor/github.com/prometheus/client_golang/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/prometheus/client_golang/NOTICE

@@ -0,0 +1,23 @@
+Prometheus instrumentation library for Go applications
+Copyright 2012-2015 The Prometheus Authors
+
+This product includes software developed at
+SoundCloud Ltd. (http://soundcloud.com/).
+
+
+The following components are included in this product:
+
+perks - a fork of https://github.com/bmizerany/perks
+https://github.com/beorn7/perks
+Copyright 2013-2015 Blake Mizerany, Björn Rabenstein
+See https://github.com/beorn7/perks/blob/master/README.md for license details.
+
+Go support for Protocol Buffers - Google's data interchange format
+http://github.com/golang/protobuf/
+Copyright 2010 The Go Authors
+See source code for license details.
+
+Support for streaming Protocol Buffer messages for the Go language (golang).
+https://github.com/matttproud/golang_protobuf_extensions
+Copyright 2013 Matt T. Proud
+Licensed under the Apache License, Version 2.0

vendor/github.com/prometheus/client_golang/prometheus/collector.go

@@ -0,0 +1,75 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+// Collector is the interface implemented by anything that can be used by
+// Prometheus to collect metrics. A Collector has to be registered for
+// collection. See Registerer.Register.
+//
+// The stock metrics provided by this package (Gauge, Counter, Summary,
+// Histogram, Untyped) are also Collectors (which only ever collect one metric,
+// namely itself). An implementer of Collector may, however, collect multiple
+// metrics in a coordinated fashion and/or create metrics on the fly. Examples
+// for collectors already implemented in this library are the metric vectors
+// (i.e. collection of multiple instances of the same Metric but with different
+// label values) like GaugeVec or SummaryVec, and the ExpvarCollector.
+type Collector interface {
+	// Describe sends the super-set of all possible descriptors of metrics
+	// collected by this Collector to the provided channel and returns once
+	// the last descriptor has been sent. The sent descriptors fulfill the
+	// consistency and uniqueness requirements described in the Desc
+	// documentation. (It is valid if one and the same Collector sends
+	// duplicate descriptors. Those duplicates are simply ignored. However,
+	// two different Collectors must not send duplicate descriptors.) This
+	// method idempotently sends the same descriptors throughout the
+	// lifetime of the Collector. If a Collector encounters an error while
+	// executing this method, it must send an invalid descriptor (created
+	// with NewInvalidDesc) to signal the error to the registry.
+	Describe(chan<- *Desc)
+	// Collect is called by the Prometheus registry when collecting
+	// metrics. The implementation sends each collected metric via the
+	// provided channel and returns once the last metric has been sent. The
+	// descriptor of each sent metric is one of those returned by
+	// Describe. Returned metrics that share the same descriptor must differ
+	// in their variable label values. This method may be called
+	// concurrently and must therefore be implemented in a concurrency safe
+	// way. Blocking occurs at the expense of total performance of rendering
+	// all registered metrics. Ideally, Collector implementations support
+	// concurrent readers.
+	Collect(chan<- Metric)
+}
+
+// selfCollector implements Collector for a single Metric so that the Metric
+// collects itself. Add it as an anonymous field to a struct that implements
+// Metric, and call init with the Metric itself as an argument.
+type selfCollector struct {
+	self Metric
+}
+
+// init provides the selfCollector with a reference to the metric it is supposed
+// to collect. It is usually called within the factory function to create a
+// metric. See example.
+func (c *selfCollector) init(self Metric) {
+	c.self = self
+}
+
+// Describe implements Collector.
+func (c *selfCollector) Describe(ch chan<- *Desc) {
+	ch <- c.self.Desc()
+}
+
+// Collect implements Collector.
+func (c *selfCollector) Collect(ch chan<- Metric) {
+	ch <- c.self
+}

vendor/github.com/prometheus/client_golang/prometheus/counter.go

@@ -0,0 +1,172 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"errors"
+)
+
+// Counter is a Metric that represents a single numerical value that only ever
+// goes up. That implies that it cannot be used to count items whose number can
+// also go down, e.g. the number of currently running goroutines. Those
+// "counters" are represented by Gauges.
+//
+// A Counter is typically used to count requests served, tasks completed, errors
+// occurred, etc.
+//
+// To create Counter instances, use NewCounter.
+type Counter interface {
+	Metric
+	Collector
+
+	// Set is used to set the Counter to an arbitrary value. It is only used
+	// if you have to transfer a value from an external counter into this
+	// Prometheus metric. Do not use it for regular handling of a
+	// Prometheus counter (as it can be used to break the contract of
+	// monotonically increasing values).
+	//
+	// Deprecated: Use NewConstMetric to create a counter for an external
+	// value. A Counter should never be set.
+	Set(float64)
+	// Inc increments the counter by 1.
+	Inc()
+	// Add adds the given value to the counter. It panics if the value is <
+	// 0.
+	Add(float64)
+}
+
+// CounterOpts is an alias for Opts. See there for doc comments.
+type CounterOpts Opts
+
+// NewCounter creates a new Counter based on the provided CounterOpts.
+func NewCounter(opts CounterOpts) Counter {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	)
+	result := &counter{value: value{desc: desc, valType: CounterValue, labelPairs: desc.constLabelPairs}}
+	result.init(result) // Init self-collection.
+	return result
+}
+
+type counter struct {
+	value
+}
+
+func (c *counter) Add(v float64) {
+	if v < 0 {
+		panic(errors.New("counter cannot decrease in value"))
+	}
+	c.value.Add(v)
+}
+
+// CounterVec is a Collector that bundles a set of Counters that all share the
+// same Desc, but have different values for their variable labels. This is used
+// if you want to count the same thing partitioned by various dimensions
+// (e.g. number of HTTP requests, partitioned by response code and
+// method). Create instances with NewCounterVec.
+//
+// CounterVec embeds MetricVec. See there for a full list of methods with
+// detailed documentation.
+type CounterVec struct {
+	*MetricVec
+}
+
+// NewCounterVec creates a new CounterVec based on the provided CounterOpts and
+// partitioned by the given label names. At least one label name must be
+// provided.
+func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &CounterVec{
+		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
+			result := &counter{value: value{
+				desc:       desc,
+				valType:    CounterValue,
+				labelPairs: makeLabelPairs(desc, lvs),
+			}}
+			result.init(result) // Init self-collection.
+			return result
+		}),
+	}
+}
+
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Counter and not a
+// Metric so that no type conversion is required.
+func (m *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Counter), err
+	}
+	return nil, err
+}
+
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns a Counter and not a Metric so that no
+// type conversion is required.
+func (m *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
+	if metric != nil {
+		return metric.(Counter), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. By not returning an
+// error, WithLabelValues allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Add(42)
+func (m *CounterVec) WithLabelValues(lvs ...string) Counter {
+	return m.MetricVec.WithLabelValues(lvs...).(Counter)
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. By not returning an error, With allows shortcuts like
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
+func (m *CounterVec) With(labels Labels) Counter {
+	return m.MetricVec.With(labels).(Counter)
+}
+
+// CounterFunc is a Counter whose value is determined at collect time by calling a
+// provided function.
+//
+// To create CounterFunc instances, use NewCounterFunc.
+type CounterFunc interface {
+	Metric
+	Collector
+}
+
+// NewCounterFunc creates a new CounterFunc based on the provided
+// CounterOpts. The value reported is determined by calling the given function
+// from within the Write method. Take into account that metric collection may
+// happen concurrently. If that results in concurrent calls to Write, like in
+// the case where a CounterFunc is directly registered with Prometheus, the
+// provided function must be concurrency-safe. The function should also honor
+// the contract for a Counter (values only go up, not down), but compliance will
+// not be checked.
+func NewCounterFunc(opts CounterOpts, function func() float64) CounterFunc {
+	return newValueFunc(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), CounterValue, function)
+}

vendor/github.com/prometheus/client_golang/prometheus/desc.go

@@ -0,0 +1,205 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"errors"
+	"fmt"
+	"regexp"
+	"sort"
+	"strings"
+
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+var (
+	metricNameRE = regexp.MustCompile(`^[a-zA-Z_][a-zA-Z0-9_:]*$`)
+	labelNameRE  = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
+)
+
+// reservedLabelPrefix is a prefix which is not legal in user-supplied
+// label names.
+const reservedLabelPrefix = "__"
+
+// Labels represents a collection of label name -> value mappings. This type is
+// commonly used with the With(Labels) and GetMetricWith(Labels) methods of
+// metric vector Collectors, e.g.:
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
+//
+// The other use-case is the specification of constant label pairs in Opts or to
+// create a Desc.
+type Labels map[string]string
+
+// Desc is the descriptor used by every Prometheus Metric. It is essentially
+// the immutable meta-data of a Metric. The normal Metric implementations
+// included in this package manage their Desc under the hood. Users only have to
+// deal with Desc if they use advanced features like the ExpvarCollector or
+// custom Collectors and Metrics.
+//
+// Descriptors registered with the same registry have to fulfill certain
+// consistency and uniqueness criteria if they share the same fully-qualified
+// name: They must have the same help string and the same label names (aka label
+// dimensions) in each, constLabels and variableLabels, but they must differ in
+// the values of the constLabels.
+//
+// Descriptors that share the same fully-qualified names and the same label
+// values of their constLabels are considered equal.
+//
+// Use NewDesc to create new Desc instances.
+type Desc struct {
+	// fqName has been built from Namespace, Subsystem, and Name.
+	fqName string
+	// help provides some helpful information about this metric.
+	help string
+	// constLabelPairs contains precalculated DTO label pairs based on
+	// the constant labels.
+	constLabelPairs []*dto.LabelPair
+	// VariableLabels contains names of labels for which the metric
+	// maintains variable values.
+	variableLabels []string
+	// id is a hash of the values of the ConstLabels and fqName. This
+	// must be unique among all registered descriptors and can therefore be
+	// used as an identifier of the descriptor.
+	id uint64
+	// dimHash is a hash of the label names (preset and variable) and the
+	// Help string. Each Desc with the same fqName must have the same
+	// dimHash.
+	dimHash uint64
+	// err is an error that occured during construction. It is reported on
+	// registration time.
+	err error
+}
+
+// NewDesc allocates and initializes a new Desc. Errors are recorded in the Desc
+// and will be reported on registration time. variableLabels and constLabels can
+// be nil if no such labels should be set. fqName and help must not be empty.
+//
+// variableLabels only contain the label names. Their label values are variable
+// and therefore not part of the Desc. (They are managed within the Metric.)
+//
+// For constLabels, the label values are constant. Therefore, they are fully
+// specified in the Desc. See the Opts documentation for the implications of
+// constant labels.
+func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *Desc {
+	d := &Desc{
+		fqName:         fqName,
+		help:           help,
+		variableLabels: variableLabels,
+	}
+	if help == "" {
+		d.err = errors.New("empty help string")
+		return d
+	}
+	if !metricNameRE.MatchString(fqName) {
+		d.err = fmt.Errorf("%q is not a valid metric name", fqName)
+		return d
+	}
+	// labelValues contains the label values of const labels (in order of
+	// their sorted label names) plus the fqName (at position 0).
+	labelValues := make([]string, 1, len(constLabels)+1)
+	labelValues[0] = fqName
+	labelNames := make([]string, 0, len(constLabels)+len(variableLabels))
+	labelNameSet := map[string]struct{}{}
+	// First add only the const label names and sort them...
+	for labelName := range constLabels {
+		if !checkLabelName(labelName) {
+			d.err = fmt.Errorf("%q is not a valid label name", labelName)
+			return d
+		}
+		labelNames = append(labelNames, labelName)
+		labelNameSet[labelName] = struct{}{}
+	}
+	sort.Strings(labelNames)
+	// ... so that we can now add const label values in the order of their names.
+	for _, labelName := range labelNames {
+		labelValues = append(labelValues, constLabels[labelName])
+	}
+	// Now add the variable label names, but prefix them with something that
+	// cannot be in a regular label name. That prevents matching the label
+	// dimension with a different mix between preset and variable labels.
+	for _, labelName := range variableLabels {
+		if !checkLabelName(labelName) {
+			d.err = fmt.Errorf("%q is not a valid label name", labelName)
+			return d
+		}
+		labelNames = append(labelNames, "$"+labelName)
+		labelNameSet[labelName] = struct{}{}
+	}
+	if len(labelNames) != len(labelNameSet) {
+		d.err = errors.New("duplicate label names")
+		return d
+	}
+	vh := hashNew()
+	for _, val := range labelValues {
+		vh = hashAdd(vh, val)
+		vh = hashAddByte(vh, separatorByte)
+	}
+	d.id = vh
+	// Sort labelNames so that order doesn't matter for the hash.
+	sort.Strings(labelNames)
+	// Now hash together (in this order) the help string and the sorted
+	// label names.
+	lh := hashNew()
+	lh = hashAdd(lh, help)
+	lh = hashAddByte(lh, separatorByte)
+	for _, labelName := range labelNames {
+		lh = hashAdd(lh, labelName)
+		lh = hashAddByte(lh, separatorByte)
+	}
+	d.dimHash = lh
+
+	d.constLabelPairs = make([]*dto.LabelPair, 0, len(constLabels))
+	for n, v := range constLabels {
+		d.constLabelPairs = append(d.constLabelPairs, &dto.LabelPair{
+			Name:  proto.String(n),
+			Value: proto.String(v),
+		})
+	}
+	sort.Sort(LabelPairSorter(d.constLabelPairs))
+	return d
+}
+
+// NewInvalidDesc returns an invalid descriptor, i.e. a descriptor with the
+// provided error set. If a collector returning such a descriptor is registered,
+// registration will fail with the provided error. NewInvalidDesc can be used by
+// a Collector to signal inability to describe itself.
+func NewInvalidDesc(err error) *Desc {
+	return &Desc{
+		err: err,
+	}
+}
+
+func (d *Desc) String() string {
+	lpStrings := make([]string, 0, len(d.constLabelPairs))
+	for _, lp := range d.constLabelPairs {
+		lpStrings = append(
+			lpStrings,
+			fmt.Sprintf("%s=%q", lp.GetName(), lp.GetValue()),
+		)
+	}
+	return fmt.Sprintf(
+		"Desc{fqName: %q, help: %q, constLabels: {%s}, variableLabels: %v}",
+		d.fqName,
+		d.help,
+		strings.Join(lpStrings, ","),
+		d.variableLabels,
+	)
+}
+
+func checkLabelName(l string) bool {
+	return labelNameRE.MatchString(l) &&
+		!strings.HasPrefix(l, reservedLabelPrefix)
+}

vendor/github.com/prometheus/client_golang/prometheus/doc.go

@@ -0,0 +1,181 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package prometheus provides metrics primitives to instrument code for
+// monitoring. It also offers a registry for metrics. Sub-packages allow to
+// expose the registered metrics via HTTP (package promhttp) or push them to a
+// Pushgateway (package push).
+//
+// All exported functions and methods are safe to be used concurrently unless
+//specified otherwise.
+//
+// A Basic Example
+//
+// As a starting point, a very basic usage example:
+//
+//    package main
+//
+//    import (
+//    	"net/http"
+//
+//    	"github.com/prometheus/client_golang/prometheus"
+//    	"github.com/prometheus/client_golang/prometheus/promhttp"
+//    )
+//
+//    var (
+//    	cpuTemp = prometheus.NewGauge(prometheus.GaugeOpts{
+//    		Name: "cpu_temperature_celsius",
+//    		Help: "Current temperature of the CPU.",
+//    	})
+//    	hdFailures = prometheus.NewCounterVec(
+//    		prometheus.CounterOpts{
+//    			Name: "hd_errors_total",
+//    			Help: "Number of hard-disk errors.",
+//    		},
+//    		[]string{"device"},
+//    	)
+//    )
+//
+//    func init() {
+//    	// Metrics have to be registered to be exposed:
+//    	prometheus.MustRegister(cpuTemp)
+//    	prometheus.MustRegister(hdFailures)
+//    }
+//
+//    func main() {
+//    	cpuTemp.Set(65.3)
+//    	hdFailures.With(prometheus.Labels{"device":"/dev/sda"}).Inc()
+//
+//    	// The Handler function provides a default handler to expose metrics
+//    	// via an HTTP server. "/metrics" is the usual endpoint for that.
+//    	http.Handle("/metrics", promhttp.Handler())
+//    	http.ListenAndServe(":8080", nil)
+//    }
+//
+//
+// This is a complete program that exports two metrics, a Gauge and a Counter,
+// the latter with a label attached to turn it into a (one-dimensional) vector.
+//
+// Metrics
+//
+// The number of exported identifiers in this package might appear a bit
+// overwhelming. Hovever, in addition to the basic plumbing shown in the example
+// above, you only need to understand the different metric types and their
+// vector versions for basic usage.
+//
+// Above, you have already touched the Counter and the Gauge. There are two more
+// advanced metric types: the Summary and Histogram. A more thorough description
+// of those four metric types can be found in the Prometheus docs:
+// https://prometheus.io/docs/concepts/metric_types/
+//
+// A fifth "type" of metric is Untyped. It behaves like a Gauge, but signals the
+// Prometheus server not to assume anything about its type.
+//
+// In addition to the fundamental metric types Gauge, Counter, Summary,
+// Histogram, and Untyped, a very important part of the Prometheus data model is
+// the partitioning of samples along dimensions called labels, which results in
+// metric vectors. The fundamental types are GaugeVec, CounterVec, SummaryVec,
+// HistogramVec, and UntypedVec.
+//
+// While only the fundamental metric types implement the Metric interface, both
+// the metrics and their vector versions implement the Collector interface. A
+// Collector manages the collection of a number of Metrics, but for convenience,
+// a Metric can also “collect itself”. Note that Gauge, Counter, Summary,
+// Histogram, and Untyped are interfaces themselves while GaugeVec, CounterVec,
+// SummaryVec, HistogramVec, and UntypedVec are not.
+//
+// To create instances of Metrics and their vector versions, you need a suitable
+// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts,
+// HistogramOpts, or UntypedOpts.
+//
+// Custom Collectors and constant Metrics
+//
+// While you could create your own implementations of Metric, most likely you
+// will only ever implement the Collector interface on your own. At a first
+// glance, a custom Collector seems handy to bundle Metrics for common
+// registration (with the prime example of the different metric vectors above,
+// which bundle all the metrics of the same name but with different labels).
+//
+// There is a more involved use case, too: If you already have metrics
+// available, created outside of the Prometheus context, you don't need the
+// interface of the various Metric types. You essentially want to mirror the
+// existing numbers into Prometheus Metrics during collection. An own
+// implementation of the Collector interface is perfect for that. You can create
+// Metric instances “on the fly” using NewConstMetric, NewConstHistogram, and
+// NewConstSummary (and their respective Must… versions). That will happen in
+// the Collect method. The Describe method has to return separate Desc
+// instances, representative of the “throw-away” metrics to be created
+// later. NewDesc comes in handy to create those Desc instances.
+//
+// The Collector example illustrates the use case. You can also look at the
+// source code of the processCollector (mirroring process metrics), the
+// goCollector (mirroring Go metrics), or the expvarCollector (mirroring expvar
+// metrics) as examples that are used in this package itself.
+//
+// If you just need to call a function to get a single float value to collect as
+// a metric, GaugeFunc, CounterFunc, or UntypedFunc might be interesting
+// shortcuts.
+//
+// Advanced Uses of the Registry
+//
+// While MustRegister is the by far most common way of registering a Collector,
+// sometimes you might want to handle the errors the registration might
+// cause. As suggested by the name, MustRegister panics if an error occurs. With
+// the Register function, the error is returned and can be handled.
+//
+// An error is returned if the registered Collector is incompatible or
+// inconsistent with already registered metrics. The registry aims for
+// consistency of the collected metrics according to the Prometheus data
+// model. Inconsistencies are ideally detected at registration time, not at
+// collect time. The former will usually be detected at start-up time of a
+// program, while the latter will only happen at scrape time, possibly not even
+// on the first scrape if the inconsistency only becomes relevant later. That is
+// the main reason why a Collector and a Metric have to describe themselves to
+// the registry.
+//
+// So far, everything we did operated on the so-called default registry, as it
+// can be found in the global DefaultRegistry variable. With NewRegistry, you
+// can create a custom registry, or you can even implement the Registerer or
+// Gatherer interfaces yourself. The methods Register and Unregister work in
+// the same way on a custom registry as the global functions Register and
+// Unregister on the default registry.
+//
+// There are a number of uses for custom registries: You can use registries
+// with special properties, see NewPedanticRegistry. You can avoid global state,
+// as it is imposed by the DefaultRegistry. You can use multiple registries at
+// the same time to expose different metrics in different ways. You can use
+// separate registries for testing purposes.
+//
+// Also note that the DefaultRegistry comes registered with a Collector for Go
+// runtime metrics (via NewGoCollector) and a Collector for process metrics (via
+// NewProcessCollector). With a custom registry, you are in control and decide
+// yourself about the Collectors to register.
+//
+// HTTP Exposition
+//
+// The Registry implements the Gatherer interface. The caller of the Gather
+// method can then expose the gathered metrics in some way. Usually, the metrics
+// are served via HTTP on the /metrics endpoint. That's happening in the example
+// above. The tools to expose metrics via HTTP are in the promhttp
+// sub-package. (The top-level functions in the prometheus package are
+// deprecated.)
+//
+// Pushing to the Pushgateway
+//
+// Function for pushing to the Pushgateway can be found in the push sub-package.
+//
+// Other Means of Exposition
+//
+// More ways of exposing metrics can easily be added. Sending metrics to
+// Graphite would be an example that will soon be implemented.
+package prometheus

vendor/github.com/prometheus/client_golang/prometheus/expvar_collector.go

@@ -0,0 +1,119 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"encoding/json"
+	"expvar"
+)
+
+type expvarCollector struct {
+	exports map[string]*Desc
+}
+
+// NewExpvarCollector returns a newly allocated expvar Collector that still has
+// to be registered with a Prometheus registry.
+//
+// An expvar Collector collects metrics from the expvar interface. It provides a
+// quick way to expose numeric values that are already exported via expvar as
+// Prometheus metrics. Note that the data models of expvar and Prometheus are
+// fundamentally different, and that the expvar Collector is inherently slower
+// than native Prometheus metrics. Thus, the expvar Collector is probably great
+// for experiments and prototying, but you should seriously consider a more
+// direct implementation of Prometheus metrics for monitoring production
+// systems.
+//
+// The exports map has the following meaning:
+//
+// The keys in the map correspond to expvar keys, i.e. for every expvar key you
+// want to export as Prometheus metric, you need an entry in the exports
+// map. The descriptor mapped to each key describes how to export the expvar
+// value. It defines the name and the help string of the Prometheus metric
+// proxying the expvar value. The type will always be Untyped.
+//
+// For descriptors without variable labels, the expvar value must be a number or
+// a bool. The number is then directly exported as the Prometheus sample
+// value. (For a bool, 'false' translates to 0 and 'true' to 1). Expvar values
+// that are not numbers or bools are silently ignored.
+//
+// If the descriptor has one variable label, the expvar value must be an expvar
+// map. The keys in the expvar map become the various values of the one
+// Prometheus label. The values in the expvar map must be numbers or bools again
+// as above.
+//
+// For descriptors with more than one variable label, the expvar must be a
+// nested expvar map, i.e. where the values of the topmost map are maps again
+// etc. until a depth is reached that corresponds to the number of labels. The
+// leaves of that structure must be numbers or bools as above to serve as the
+// sample values.
+//
+// Anything that does not fit into the scheme above is silently ignored.
+func NewExpvarCollector(exports map[string]*Desc) Collector {
+	return &expvarCollector{
+		exports: exports,
+	}
+}
+
+// Describe implements Collector.
+func (e *expvarCollector) Describe(ch chan<- *Desc) {
+	for _, desc := range e.exports {
+		ch <- desc
+	}
+}
+
+// Collect implements Collector.
+func (e *expvarCollector) Collect(ch chan<- Metric) {
+	for name, desc := range e.exports {
+		var m Metric
+		expVar := expvar.Get(name)
+		if expVar == nil {
+			continue
+		}
+		var v interface{}
+		labels := make([]string, len(desc.variableLabels))
+		if err := json.Unmarshal([]byte(expVar.String()), &v); err != nil {
+			ch <- NewInvalidMetric(desc, err)
+			continue
+		}
+		var processValue func(v interface{}, i int)
+		processValue = func(v interface{}, i int) {
+			if i >= len(labels) {
+				copiedLabels := append(make([]string, 0, len(labels)), labels...)
+				switch v := v.(type) {
+				case float64:
+					m = MustNewConstMetric(desc, UntypedValue, v, copiedLabels...)
+				case bool:
+					if v {
+						m = MustNewConstMetric(desc, UntypedValue, 1, copiedLabels...)
+					} else {
+						m = MustNewConstMetric(desc, UntypedValue, 0, copiedLabels...)
+					}
+				default:
+					return
+				}
+				ch <- m
+				return
+			}
+			vm, ok := v.(map[string]interface{})
+			if !ok {
+				return
+			}
+			for lv, val := range vm {
+				labels[i] = lv
+				processValue(val, i+1)
+			}
+		}
+		processValue(v, 0)
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/fnv.go

@@ -0,0 +1,29 @@
+package prometheus
+
+// Inline and byte-free variant of hash/fnv's fnv64a.
+
+const (
+	offset64 = 14695981039346656037
+	prime64  = 1099511628211
+)
+
+// hashNew initializies a new fnv64a hash value.
+func hashNew() uint64 {
+	return offset64
+}
+
+// hashAdd adds a string to a fnv64a hash value, returning the updated hash.
+func hashAdd(h uint64, s string) uint64 {
+	for i := 0; i < len(s); i++ {
+		h ^= uint64(s[i])
+		h *= prime64
+	}
+	return h
+}
+
+// hashAddByte adds a byte to a fnv64a hash value, returning the updated hash.
+func hashAddByte(h uint64, b byte) uint64 {
+	h ^= uint64(b)
+	h *= prime64
+	return h
+}

vendor/github.com/prometheus/client_golang/prometheus/gauge.go

@@ -0,0 +1,140 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+// Gauge is a Metric that represents a single numerical value that can
+// arbitrarily go up and down.
+//
+// A Gauge is typically used for measured values like temperatures or current
+// memory usage, but also "counts" that can go up and down, like the number of
+// running goroutines.
+//
+// To create Gauge instances, use NewGauge.
+type Gauge interface {
+	Metric
+	Collector
+
+	// Set sets the Gauge to an arbitrary value.
+	Set(float64)
+	// Inc increments the Gauge by 1.
+	Inc()
+	// Dec decrements the Gauge by 1.
+	Dec()
+	// Add adds the given value to the Gauge. (The value can be
+	// negative, resulting in a decrease of the Gauge.)
+	Add(float64)
+	// Sub subtracts the given value from the Gauge. (The value can be
+	// negative, resulting in an increase of the Gauge.)
+	Sub(float64)
+}
+
+// GaugeOpts is an alias for Opts. See there for doc comments.
+type GaugeOpts Opts
+
+// NewGauge creates a new Gauge based on the provided GaugeOpts.
+func NewGauge(opts GaugeOpts) Gauge {
+	return newValue(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), GaugeValue, 0)
+}
+
+// GaugeVec is a Collector that bundles a set of Gauges that all share the same
+// Desc, but have different values for their variable labels. This is used if
+// you want to count the same thing partitioned by various dimensions
+// (e.g. number of operations queued, partitioned by user and operation
+// type). Create instances with NewGaugeVec.
+type GaugeVec struct {
+	*MetricVec
+}
+
+// NewGaugeVec creates a new GaugeVec based on the provided GaugeOpts and
+// partitioned by the given label names. At least one label name must be
+// provided.
+func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &GaugeVec{
+		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
+			return newValue(desc, GaugeValue, 0, lvs...)
+		}),
+	}
+}
+
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Gauge and not a
+// Metric so that no type conversion is required.
+func (m *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Gauge), err
+	}
+	return nil, err
+}
+
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns a Gauge and not a Metric so that no
+// type conversion is required.
+func (m *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
+	if metric != nil {
+		return metric.(Gauge), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. By not returning an
+// error, WithLabelValues allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Add(42)
+func (m *GaugeVec) WithLabelValues(lvs ...string) Gauge {
+	return m.MetricVec.WithLabelValues(lvs...).(Gauge)
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. By not returning an error, With allows shortcuts like
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
+func (m *GaugeVec) With(labels Labels) Gauge {
+	return m.MetricVec.With(labels).(Gauge)
+}
+
+// GaugeFunc is a Gauge whose value is determined at collect time by calling a
+// provided function.
+//
+// To create GaugeFunc instances, use NewGaugeFunc.
+type GaugeFunc interface {
+	Metric
+	Collector
+}
+
+// NewGaugeFunc creates a new GaugeFunc based on the provided GaugeOpts. The
+// value reported is determined by calling the given function from within the
+// Write method. Take into account that metric collection may happen
+// concurrently. If that results in concurrent calls to Write, like in the case
+// where a GaugeFunc is directly registered with Prometheus, the provided
+// function must be concurrency-safe.
+func NewGaugeFunc(opts GaugeOpts, function func() float64) GaugeFunc {
+	return newValueFunc(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), GaugeValue, function)
+}

vendor/github.com/prometheus/client_golang/prometheus/go_collector.go

@@ -0,0 +1,263 @@
+package prometheus
+
+import (
+	"fmt"
+	"runtime"
+	"runtime/debug"
+	"time"
+)
+
+type goCollector struct {
+	goroutines Gauge
+	gcDesc     *Desc
+
+	// metrics to describe and collect
+	metrics memStatsMetrics
+}
+
+// NewGoCollector returns a collector which exports metrics about the current
+// go process.
+func NewGoCollector() Collector {
+	return &goCollector{
+		goroutines: NewGauge(GaugeOpts{
+			Namespace: "go",
+			Name:      "goroutines",
+			Help:      "Number of goroutines that currently exist.",
+		}),
+		gcDesc: NewDesc(
+			"go_gc_duration_seconds",
+			"A summary of the GC invocation durations.",
+			nil, nil),
+		metrics: memStatsMetrics{
+			{
+				desc: NewDesc(
+					memstatNamespace("alloc_bytes"),
+					"Number of bytes allocated and still in use.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Alloc) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("alloc_bytes_total"),
+					"Total number of bytes allocated, even if freed.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.TotalAlloc) },
+				valType: CounterValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("sys_bytes"),
+					"Number of bytes obtained by system. Sum of all system allocations.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Sys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("lookups_total"),
+					"Total number of pointer lookups.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Lookups) },
+				valType: CounterValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("mallocs_total"),
+					"Total number of mallocs.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Mallocs) },
+				valType: CounterValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("frees_total"),
+					"Total number of frees.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Frees) },
+				valType: CounterValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("heap_alloc_bytes"),
+					"Number of heap bytes allocated and still in use.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapAlloc) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("heap_sys_bytes"),
+					"Number of heap bytes obtained from system.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("heap_idle_bytes"),
+					"Number of heap bytes waiting to be used.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapIdle) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("heap_inuse_bytes"),
+					"Number of heap bytes that are in use.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapInuse) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("heap_released_bytes_total"),
+					"Total number of heap bytes released to OS.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapReleased) },
+				valType: CounterValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("heap_objects"),
+					"Number of allocated objects.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapObjects) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("stack_inuse_bytes"),
+					"Number of bytes in use by the stack allocator.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.StackInuse) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("stack_sys_bytes"),
+					"Number of bytes obtained from system for stack allocator.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.StackSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("mspan_inuse_bytes"),
+					"Number of bytes in use by mspan structures.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MSpanInuse) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("mspan_sys_bytes"),
+					"Number of bytes used for mspan structures obtained from system.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MSpanSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("mcache_inuse_bytes"),
+					"Number of bytes in use by mcache structures.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MCacheInuse) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("mcache_sys_bytes"),
+					"Number of bytes used for mcache structures obtained from system.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MCacheSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("buck_hash_sys_bytes"),
+					"Number of bytes used by the profiling bucket hash table.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.BuckHashSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("gc_sys_bytes"),
+					"Number of bytes used for garbage collection system metadata.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.GCSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("other_sys_bytes"),
+					"Number of bytes used for other system allocations.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.OtherSys) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("next_gc_bytes"),
+					"Number of heap bytes when next garbage collection will take place.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.NextGC) },
+				valType: GaugeValue,
+			}, {
+				desc: NewDesc(
+					memstatNamespace("last_gc_time_seconds"),
+					"Number of seconds since 1970 of last garbage collection.",
+					nil, nil,
+				),
+				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.LastGC) / 1e9 },
+				valType: GaugeValue,
+			},
+		},
+	}
+}
+
+func memstatNamespace(s string) string {
+	return fmt.Sprintf("go_memstats_%s", s)
+}
+
+// Describe returns all descriptions of the collector.
+func (c *goCollector) Describe(ch chan<- *Desc) {
+	ch <- c.goroutines.Desc()
+	ch <- c.gcDesc
+
+	for _, i := range c.metrics {
+		ch <- i.desc
+	}
+}
+
+// Collect returns the current state of all metrics of the collector.
+func (c *goCollector) Collect(ch chan<- Metric) {
+	c.goroutines.Set(float64(runtime.NumGoroutine()))
+	ch <- c.goroutines
+
+	var stats debug.GCStats
+	stats.PauseQuantiles = make([]time.Duration, 5)
+	debug.ReadGCStats(&stats)
+
+	quantiles := make(map[float64]float64)
+	for idx, pq := range stats.PauseQuantiles[1:] {
+		quantiles[float64(idx+1)/float64(len(stats.PauseQuantiles)-1)] = pq.Seconds()
+	}
+	quantiles[0.0] = stats.PauseQuantiles[0].Seconds()
+	ch <- MustNewConstSummary(c.gcDesc, uint64(stats.NumGC), float64(stats.PauseTotal.Seconds()), quantiles)
+
+	ms := &runtime.MemStats{}
+	runtime.ReadMemStats(ms)
+	for _, i := range c.metrics {
+		ch <- MustNewConstMetric(i.desc, i.valType, i.eval(ms))
+	}
+}
+
+// memStatsMetrics provide description, value, and value type for memstat metrics.
+type memStatsMetrics []struct {
+	desc    *Desc
+	eval    func(*runtime.MemStats) float64
+	valType ValueType
+}

vendor/github.com/prometheus/client_golang/prometheus/histogram.go

@@ -0,0 +1,444 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"fmt"
+	"math"
+	"sort"
+	"sync/atomic"
+
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// A Histogram counts individual observations from an event or sample stream in
+// configurable buckets. Similar to a summary, it also provides a sum of
+// observations and an observation count.
+//
+// On the Prometheus server, quantiles can be calculated from a Histogram using
+// the histogram_quantile function in the query language.
+//
+// Note that Histograms, in contrast to Summaries, can be aggregated with the
+// Prometheus query language (see the documentation for detailed
+// procedures). However, Histograms require the user to pre-define suitable
+// buckets, and they are in general less accurate. The Observe method of a
+// Histogram has a very low performance overhead in comparison with the Observe
+// method of a Summary.
+//
+// To create Histogram instances, use NewHistogram.
+type Histogram interface {
+	Metric
+	Collector
+
+	// Observe adds a single observation to the histogram.
+	Observe(float64)
+}
+
+// bucketLabel is used for the label that defines the upper bound of a
+// bucket of a histogram ("le" -> "less or equal").
+const bucketLabel = "le"
+
+// DefBuckets are the default Histogram buckets. The default buckets are
+// tailored to broadly measure the response time (in seconds) of a network
+// service. Most likely, however, you will be required to define buckets
+// customized to your use case.
+var (
+	DefBuckets = []float64{.005, .01, .025, .05, .1, .25, .5, 1, 2.5, 5, 10}
+
+	errBucketLabelNotAllowed = fmt.Errorf(
+		"%q is not allowed as label name in histograms", bucketLabel,
+	)
+)
+
+// LinearBuckets creates 'count' buckets, each 'width' wide, where the lowest
+// bucket has an upper bound of 'start'. The final +Inf bucket is not counted
+// and not included in the returned slice. The returned slice is meant to be
+// used for the Buckets field of HistogramOpts.
+//
+// The function panics if 'count' is zero or negative.
+func LinearBuckets(start, width float64, count int) []float64 {
+	if count < 1 {
+		panic("LinearBuckets needs a positive count")
+	}
+	buckets := make([]float64, count)
+	for i := range buckets {
+		buckets[i] = start
+		start += width
+	}
+	return buckets
+}
+
+// ExponentialBuckets creates 'count' buckets, where the lowest bucket has an
+// upper bound of 'start' and each following bucket's upper bound is 'factor'
+// times the previous bucket's upper bound. The final +Inf bucket is not counted
+// and not included in the returned slice. The returned slice is meant to be
+// used for the Buckets field of HistogramOpts.
+//
+// The function panics if 'count' is 0 or negative, if 'start' is 0 or negative,
+// or if 'factor' is less than or equal 1.
+func ExponentialBuckets(start, factor float64, count int) []float64 {
+	if count < 1 {
+		panic("ExponentialBuckets needs a positive count")
+	}
+	if start <= 0 {
+		panic("ExponentialBuckets needs a positive start value")
+	}
+	if factor <= 1 {
+		panic("ExponentialBuckets needs a factor greater than 1")
+	}
+	buckets := make([]float64, count)
+	for i := range buckets {
+		buckets[i] = start
+		start *= factor
+	}
+	return buckets
+}
+
+// HistogramOpts bundles the options for creating a Histogram metric. It is
+// mandatory to set Name and Help to a non-empty string. All other fields are
+// optional and can safely be left at their zero value.
+type HistogramOpts struct {
+	// Namespace, Subsystem, and Name are components of the fully-qualified
+	// name of the Histogram (created by joining these components with
+	// "_"). Only Name is mandatory, the others merely help structuring the
+	// name. Note that the fully-qualified name of the Histogram must be a
+	// valid Prometheus metric name.
+	Namespace string
+	Subsystem string
+	Name      string
+
+	// Help provides information about this Histogram. Mandatory!
+	//
+	// Metrics with the same fully-qualified name must have the same Help
+	// string.
+	Help string
+
+	// ConstLabels are used to attach fixed labels to this
+	// Histogram. Histograms with the same fully-qualified name must have the
+	// same label names in their ConstLabels.
+	//
+	// Note that in most cases, labels have a value that varies during the
+	// lifetime of a process. Those labels are usually managed with a
+	// HistogramVec. ConstLabels serve only special purposes. One is for the
+	// special case where the value of a label does not change during the
+	// lifetime of a process, e.g. if the revision of the running binary is
+	// put into a label. Another, more advanced purpose is if more than one
+	// Collector needs to collect Histograms with the same fully-qualified
+	// name. In that case, those Summaries must differ in the values of
+	// their ConstLabels. See the Collector examples.
+	//
+	// If the value of a label never changes (not even between binaries),
+	// that label most likely should not be a label at all (but part of the
+	// metric name).
+	ConstLabels Labels
+
+	// Buckets defines the buckets into which observations are counted. Each
+	// element in the slice is the upper inclusive bound of a bucket. The
+	// values must be sorted in strictly increasing order. There is no need
+	// to add a highest bucket with +Inf bound, it will be added
+	// implicitly. The default value is DefBuckets.
+	Buckets []float64
+}
+
+// NewHistogram creates a new Histogram based on the provided HistogramOpts. It
+// panics if the buckets in HistogramOpts are not in strictly increasing order.
+func NewHistogram(opts HistogramOpts) Histogram {
+	return newHistogram(
+		NewDesc(
+			BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+			opts.Help,
+			nil,
+			opts.ConstLabels,
+		),
+		opts,
+	)
+}
+
+func newHistogram(desc *Desc, opts HistogramOpts, labelValues ...string) Histogram {
+	if len(desc.variableLabels) != len(labelValues) {
+		panic(errInconsistentCardinality)
+	}
+
+	for _, n := range desc.variableLabels {
+		if n == bucketLabel {
+			panic(errBucketLabelNotAllowed)
+		}
+	}
+	for _, lp := range desc.constLabelPairs {
+		if lp.GetName() == bucketLabel {
+			panic(errBucketLabelNotAllowed)
+		}
+	}
+
+	if len(opts.Buckets) == 0 {
+		opts.Buckets = DefBuckets
+	}
+
+	h := &histogram{
+		desc:        desc,
+		upperBounds: opts.Buckets,
+		labelPairs:  makeLabelPairs(desc, labelValues),
+	}
+	for i, upperBound := range h.upperBounds {
+		if i < len(h.upperBounds)-1 {
+			if upperBound >= h.upperBounds[i+1] {
+				panic(fmt.Errorf(
+					"histogram buckets must be in increasing order: %f >= %f",
+					upperBound, h.upperBounds[i+1],
+				))
+			}
+		} else {
+			if math.IsInf(upperBound, +1) {
+				// The +Inf bucket is implicit. Remove it here.
+				h.upperBounds = h.upperBounds[:i]
+			}
+		}
+	}
+	// Finally we know the final length of h.upperBounds and can make counts.
+	h.counts = make([]uint64, len(h.upperBounds))
+
+	h.init(h) // Init self-collection.
+	return h
+}
+
+type histogram struct {
+	// sumBits contains the bits of the float64 representing the sum of all
+	// observations. sumBits and count have to go first in the struct to
+	// guarantee alignment for atomic operations.
+	// http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+	sumBits uint64
+	count   uint64
+
+	selfCollector
+	// Note that there is no mutex required.
+
+	desc *Desc
+
+	upperBounds []float64
+	counts      []uint64
+
+	labelPairs []*dto.LabelPair
+}
+
+func (h *histogram) Desc() *Desc {
+	return h.desc
+}
+
+func (h *histogram) Observe(v float64) {
+	// TODO(beorn7): For small numbers of buckets (<30), a linear search is
+	// slightly faster than the binary search. If we really care, we could
+	// switch from one search strategy to the other depending on the number
+	// of buckets.
+	//
+	// Microbenchmarks (BenchmarkHistogramNoLabels):
+	// 11 buckets: 38.3 ns/op linear - binary 48.7 ns/op
+	// 100 buckets: 78.1 ns/op linear - binary 54.9 ns/op
+	// 300 buckets: 154 ns/op linear - binary 61.6 ns/op
+	i := sort.SearchFloat64s(h.upperBounds, v)
+	if i < len(h.counts) {
+		atomic.AddUint64(&h.counts[i], 1)
+	}
+	atomic.AddUint64(&h.count, 1)
+	for {
+		oldBits := atomic.LoadUint64(&h.sumBits)
+		newBits := math.Float64bits(math.Float64frombits(oldBits) + v)
+		if atomic.CompareAndSwapUint64(&h.sumBits, oldBits, newBits) {
+			break
+		}
+	}
+}
+
+func (h *histogram) Write(out *dto.Metric) error {
+	his := &dto.Histogram{}
+	buckets := make([]*dto.Bucket, len(h.upperBounds))
+
+	his.SampleSum = proto.Float64(math.Float64frombits(atomic.LoadUint64(&h.sumBits)))
+	his.SampleCount = proto.Uint64(atomic.LoadUint64(&h.count))
+	var count uint64
+	for i, upperBound := range h.upperBounds {
+		count += atomic.LoadUint64(&h.counts[i])
+		buckets[i] = &dto.Bucket{
+			CumulativeCount: proto.Uint64(count),
+			UpperBound:      proto.Float64(upperBound),
+		}
+	}
+	his.Bucket = buckets
+	out.Histogram = his
+	out.Label = h.labelPairs
+	return nil
+}
+
+// HistogramVec is a Collector that bundles a set of Histograms that all share the
+// same Desc, but have different values for their variable labels. This is used
+// if you want to count the same thing partitioned by various dimensions
+// (e.g. HTTP request latencies, partitioned by status code and method). Create
+// instances with NewHistogramVec.
+type HistogramVec struct {
+	*MetricVec
+}
+
+// NewHistogramVec creates a new HistogramVec based on the provided HistogramOpts and
+// partitioned by the given label names. At least one label name must be
+// provided.
+func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &HistogramVec{
+		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
+			return newHistogram(desc, opts, lvs...)
+		}),
+	}
+}
+
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Histogram and not a
+// Metric so that no type conversion is required.
+func (m *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Histogram, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Histogram), err
+	}
+	return nil, err
+}
+
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns a Histogram and not a Metric so that no
+// type conversion is required.
+func (m *HistogramVec) GetMetricWith(labels Labels) (Histogram, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
+	if metric != nil {
+		return metric.(Histogram), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. By not returning an
+// error, WithLabelValues allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Observe(42.21)
+func (m *HistogramVec) WithLabelValues(lvs ...string) Histogram {
+	return m.MetricVec.WithLabelValues(lvs...).(Histogram)
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. By not returning an error, With allows shortcuts like
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Observe(42.21)
+func (m *HistogramVec) With(labels Labels) Histogram {
+	return m.MetricVec.With(labels).(Histogram)
+}
+
+type constHistogram struct {
+	desc       *Desc
+	count      uint64
+	sum        float64
+	buckets    map[float64]uint64
+	labelPairs []*dto.LabelPair
+}
+
+func (h *constHistogram) Desc() *Desc {
+	return h.desc
+}
+
+func (h *constHistogram) Write(out *dto.Metric) error {
+	his := &dto.Histogram{}
+	buckets := make([]*dto.Bucket, 0, len(h.buckets))
+
+	his.SampleCount = proto.Uint64(h.count)
+	his.SampleSum = proto.Float64(h.sum)
+
+	for upperBound, count := range h.buckets {
+		buckets = append(buckets, &dto.Bucket{
+			CumulativeCount: proto.Uint64(count),
+			UpperBound:      proto.Float64(upperBound),
+		})
+	}
+
+	if len(buckets) > 0 {
+		sort.Sort(buckSort(buckets))
+	}
+	his.Bucket = buckets
+
+	out.Histogram = his
+	out.Label = h.labelPairs
+
+	return nil
+}
+
+// NewConstHistogram returns a metric representing a Prometheus histogram with
+// fixed values for the count, sum, and bucket counts. As those parameters
+// cannot be changed, the returned value does not implement the Histogram
+// interface (but only the Metric interface). Users of this package will not
+// have much use for it in regular operations. However, when implementing custom
+// Collectors, it is useful as a throw-away metric that is generated on the fly
+// to send it to Prometheus in the Collect method.
+//
+// buckets is a map of upper bounds to cumulative counts, excluding the +Inf
+// bucket.
+//
+// NewConstHistogram returns an error if the length of labelValues is not
+// consistent with the variable labels in Desc.
+func NewConstHistogram(
+	desc *Desc,
+	count uint64,
+	sum float64,
+	buckets map[float64]uint64,
+	labelValues ...string,
+) (Metric, error) {
+	if len(desc.variableLabels) != len(labelValues) {
+		return nil, errInconsistentCardinality
+	}
+	return &constHistogram{
+		desc:       desc,
+		count:      count,
+		sum:        sum,
+		buckets:    buckets,
+		labelPairs: makeLabelPairs(desc, labelValues),
+	}, nil
+}
+
+// MustNewConstHistogram is a version of NewConstHistogram that panics where
+// NewConstMetric would have returned an error.
+func MustNewConstHistogram(
+	desc *Desc,
+	count uint64,
+	sum float64,
+	buckets map[float64]uint64,
+	labelValues ...string,
+) Metric {
+	m, err := NewConstHistogram(desc, count, sum, buckets, labelValues...)
+	if err != nil {
+		panic(err)
+	}
+	return m
+}
+
+type buckSort []*dto.Bucket
+
+func (s buckSort) Len() int {
+	return len(s)
+}
+
+func (s buckSort) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s buckSort) Less(i, j int) bool {
+	return s[i].GetUpperBound() < s[j].GetUpperBound()
+}

vendor/github.com/prometheus/client_golang/prometheus/http.go

@@ -0,0 +1,490 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"bufio"
+	"bytes"
+	"compress/gzip"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/prometheus/common/expfmt"
+)
+
+// TODO(beorn7): Remove this whole file. It is a partial mirror of
+// promhttp/http.go (to avoid circular import chains) where everything HTTP
+// related should live. The functions here are just for avoiding
+// breakage. Everything is deprecated.
+
+const (
+	contentTypeHeader     = "Content-Type"
+	contentLengthHeader   = "Content-Length"
+	contentEncodingHeader = "Content-Encoding"
+	acceptEncodingHeader  = "Accept-Encoding"
+)
+
+var bufPool sync.Pool
+
+func getBuf() *bytes.Buffer {
+	buf := bufPool.Get()
+	if buf == nil {
+		return &bytes.Buffer{}
+	}
+	return buf.(*bytes.Buffer)
+}
+
+func giveBuf(buf *bytes.Buffer) {
+	buf.Reset()
+	bufPool.Put(buf)
+}
+
+// Handler returns an HTTP handler for the DefaultGatherer. It is
+// already instrumented with InstrumentHandler (using "prometheus" as handler
+// name).
+//
+// Deprecated: Please note the issues described in the doc comment of
+// InstrumentHandler. You might want to consider using promhttp.Handler instead
+// (which is non instrumented).
+func Handler() http.Handler {
+	return InstrumentHandler("prometheus", UninstrumentedHandler())
+}
+
+// UninstrumentedHandler returns an HTTP handler for the DefaultGatherer.
+//
+// Deprecated: Use promhttp.Handler instead. See there for further documentation.
+func UninstrumentedHandler() http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		mfs, err := DefaultGatherer.Gather()
+		if err != nil {
+			http.Error(w, "An error has occurred during metrics collection:\n\n"+err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		contentType := expfmt.Negotiate(req.Header)
+		buf := getBuf()
+		defer giveBuf(buf)
+		writer, encoding := decorateWriter(req, buf)
+		enc := expfmt.NewEncoder(writer, contentType)
+		var lastErr error
+		for _, mf := range mfs {
+			if err := enc.Encode(mf); err != nil {
+				lastErr = err
+				http.Error(w, "An error has occurred during metrics encoding:\n\n"+err.Error(), http.StatusInternalServerError)
+				return
+			}
+		}
+		if closer, ok := writer.(io.Closer); ok {
+			closer.Close()
+		}
+		if lastErr != nil && buf.Len() == 0 {
+			http.Error(w, "No metrics encoded, last error:\n\n"+err.Error(), http.StatusInternalServerError)
+			return
+		}
+		header := w.Header()
+		header.Set(contentTypeHeader, string(contentType))
+		header.Set(contentLengthHeader, fmt.Sprint(buf.Len()))
+		if encoding != "" {
+			header.Set(contentEncodingHeader, encoding)
+		}
+		w.Write(buf.Bytes())
+	})
+}
+
+// decorateWriter wraps a writer to handle gzip compression if requested.  It
+// returns the decorated writer and the appropriate "Content-Encoding" header
+// (which is empty if no compression is enabled).
+func decorateWriter(request *http.Request, writer io.Writer) (io.Writer, string) {
+	header := request.Header.Get(acceptEncodingHeader)
+	parts := strings.Split(header, ",")
+	for _, part := range parts {
+		part := strings.TrimSpace(part)
+		if part == "gzip" || strings.HasPrefix(part, "gzip;") {
+			return gzip.NewWriter(writer), "gzip"
+		}
+	}
+	return writer, ""
+}
+
+var instLabels = []string{"method", "code"}
+
+type nower interface {
+	Now() time.Time
+}
+
+type nowFunc func() time.Time
+
+func (n nowFunc) Now() time.Time {
+	return n()
+}
+
+var now nower = nowFunc(func() time.Time {
+	return time.Now()
+})
+
+func nowSeries(t ...time.Time) nower {
+	return nowFunc(func() time.Time {
+		defer func() {
+			t = t[1:]
+		}()
+
+		return t[0]
+	})
+}
+
+// InstrumentHandler wraps the given HTTP handler for instrumentation. It
+// registers four metric collectors (if not already done) and reports HTTP
+// metrics to the (newly or already) registered collectors: http_requests_total
+// (CounterVec), http_request_duration_microseconds (Summary),
+// http_request_size_bytes (Summary), http_response_size_bytes (Summary). Each
+// has a constant label named "handler" with the provided handlerName as
+// value. http_requests_total is a metric vector partitioned by HTTP method
+// (label name "method") and HTTP status code (label name "code").
+//
+// Deprecated: InstrumentHandler has several issues:
+//
+// - It uses Summaries rather than Histograms. Summaries are not useful if
+// aggregation across multiple instances is required.
+//
+// - It uses microseconds as unit, which is deprecated and should be replaced by
+// seconds.
+//
+// - The size of the request is calculated in a separate goroutine. Since this
+// calculator requires access to the request header, it creates a race with
+// any writes to the header performed during request handling.
+// httputil.ReverseProxy is a prominent example for a handler
+// performing such writes.
+//
+// Upcoming versions of this package will provide ways of instrumenting HTTP
+// handlers that are more flexible and have fewer issues. Please prefer direct
+// instrumentation in the meantime.
+func InstrumentHandler(handlerName string, handler http.Handler) http.HandlerFunc {
+	return InstrumentHandlerFunc(handlerName, handler.ServeHTTP)
+}
+
+// InstrumentHandlerFunc wraps the given function for instrumentation. It
+// otherwise works in the same way as InstrumentHandler (and shares the same
+// issues).
+//
+// Deprecated: InstrumentHandlerFunc is deprecated for the same reasons as
+// InstrumentHandler is.
+func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
+	return InstrumentHandlerFuncWithOpts(
+		SummaryOpts{
+			Subsystem:   "http",
+			ConstLabels: Labels{"handler": handlerName},
+		},
+		handlerFunc,
+	)
+}
+
+// InstrumentHandlerWithOpts works like InstrumentHandler (and shares the same
+// issues) but provides more flexibility (at the cost of a more complex call
+// syntax). As InstrumentHandler, this function registers four metric
+// collectors, but it uses the provided SummaryOpts to create them. However, the
+// fields "Name" and "Help" in the SummaryOpts are ignored. "Name" is replaced
+// by "requests_total", "request_duration_microseconds", "request_size_bytes",
+// and "response_size_bytes", respectively. "Help" is replaced by an appropriate
+// help string. The names of the variable labels of the http_requests_total
+// CounterVec are "method" (get, post, etc.), and "code" (HTTP status code).
+//
+// If InstrumentHandlerWithOpts is called as follows, it mimics exactly the
+// behavior of InstrumentHandler:
+//
+//     prometheus.InstrumentHandlerWithOpts(
+//         prometheus.SummaryOpts{
+//              Subsystem:   "http",
+//              ConstLabels: prometheus.Labels{"handler": handlerName},
+//         },
+//         handler,
+//     )
+//
+// Technical detail: "requests_total" is a CounterVec, not a SummaryVec, so it
+// cannot use SummaryOpts. Instead, a CounterOpts struct is created internally,
+// and all its fields are set to the equally named fields in the provided
+// SummaryOpts.
+//
+// Deprecated: InstrumentHandlerWithOpts is deprecated for the same reasons as
+// InstrumentHandler is.
+func InstrumentHandlerWithOpts(opts SummaryOpts, handler http.Handler) http.HandlerFunc {
+	return InstrumentHandlerFuncWithOpts(opts, handler.ServeHTTP)
+}
+
+// InstrumentHandlerFuncWithOpts works like InstrumentHandlerFunc (and shares
+// the same issues) but provides more flexibility (at the cost of a more complex
+// call syntax). See InstrumentHandlerWithOpts for details how the provided
+// SummaryOpts are used.
+//
+// Deprecated: InstrumentHandlerFuncWithOpts is deprecated for the same reasons
+// as InstrumentHandler is.
+func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
+	reqCnt := NewCounterVec(
+		CounterOpts{
+			Namespace:   opts.Namespace,
+			Subsystem:   opts.Subsystem,
+			Name:        "requests_total",
+			Help:        "Total number of HTTP requests made.",
+			ConstLabels: opts.ConstLabels,
+		},
+		instLabels,
+	)
+
+	opts.Name = "request_duration_microseconds"
+	opts.Help = "The HTTP request latencies in microseconds."
+	reqDur := NewSummary(opts)
+
+	opts.Name = "request_size_bytes"
+	opts.Help = "The HTTP request sizes in bytes."
+	reqSz := NewSummary(opts)
+
+	opts.Name = "response_size_bytes"
+	opts.Help = "The HTTP response sizes in bytes."
+	resSz := NewSummary(opts)
+
+	regReqCnt := MustRegisterOrGet(reqCnt).(*CounterVec)
+	regReqDur := MustRegisterOrGet(reqDur).(Summary)
+	regReqSz := MustRegisterOrGet(reqSz).(Summary)
+	regResSz := MustRegisterOrGet(resSz).(Summary)
+
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		now := time.Now()
+
+		delegate := &responseWriterDelegator{ResponseWriter: w}
+		out := make(chan int)
+		urlLen := 0
+		if r.URL != nil {
+			urlLen = len(r.URL.String())
+		}
+		go computeApproximateRequestSize(r, out, urlLen)
+
+		_, cn := w.(http.CloseNotifier)
+		_, fl := w.(http.Flusher)
+		_, hj := w.(http.Hijacker)
+		_, rf := w.(io.ReaderFrom)
+		var rw http.ResponseWriter
+		if cn && fl && hj && rf {
+			rw = &fancyResponseWriterDelegator{delegate}
+		} else {
+			rw = delegate
+		}
+		handlerFunc(rw, r)
+
+		elapsed := float64(time.Since(now)) / float64(time.Microsecond)
+
+		method := sanitizeMethod(r.Method)
+		code := sanitizeCode(delegate.status)
+		regReqCnt.WithLabelValues(method, code).Inc()
+		regReqDur.Observe(elapsed)
+		regResSz.Observe(float64(delegate.written))
+		regReqSz.Observe(float64(<-out))
+	})
+}
+
+func computeApproximateRequestSize(r *http.Request, out chan int, s int) {
+	s += len(r.Method)
+	s += len(r.Proto)
+	for name, values := range r.Header {
+		s += len(name)
+		for _, value := range values {
+			s += len(value)
+		}
+	}
+	s += len(r.Host)
+
+	// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
+
+	if r.ContentLength != -1 {
+		s += int(r.ContentLength)
+	}
+	out <- s
+}
+
+type responseWriterDelegator struct {
+	http.ResponseWriter
+
+	handler, method string
+	status          int
+	written         int64
+	wroteHeader     bool
+}
+
+func (r *responseWriterDelegator) WriteHeader(code int) {
+	r.status = code
+	r.wroteHeader = true
+	r.ResponseWriter.WriteHeader(code)
+}
+
+func (r *responseWriterDelegator) Write(b []byte) (int, error) {
+	if !r.wroteHeader {
+		r.WriteHeader(http.StatusOK)
+	}
+	n, err := r.ResponseWriter.Write(b)
+	r.written += int64(n)
+	return n, err
+}
+
+type fancyResponseWriterDelegator struct {
+	*responseWriterDelegator
+}
+
+func (f *fancyResponseWriterDelegator) CloseNotify() <-chan bool {
+	return f.ResponseWriter.(http.CloseNotifier).CloseNotify()
+}
+
+func (f *fancyResponseWriterDelegator) Flush() {
+	f.ResponseWriter.(http.Flusher).Flush()
+}
+
+func (f *fancyResponseWriterDelegator) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	return f.ResponseWriter.(http.Hijacker).Hijack()
+}
+
+func (f *fancyResponseWriterDelegator) ReadFrom(r io.Reader) (int64, error) {
+	if !f.wroteHeader {
+		f.WriteHeader(http.StatusOK)
+	}
+	n, err := f.ResponseWriter.(io.ReaderFrom).ReadFrom(r)
+	f.written += n
+	return n, err
+}
+
+func sanitizeMethod(m string) string {
+	switch m {
+	case "GET", "get":
+		return "get"
+	case "PUT", "put":
+		return "put"
+	case "HEAD", "head":
+		return "head"
+	case "POST", "post":
+		return "post"
+	case "DELETE", "delete":
+		return "delete"
+	case "CONNECT", "connect":
+		return "connect"
+	case "OPTIONS", "options":
+		return "options"
+	case "NOTIFY", "notify":
+		return "notify"
+	default:
+		return strings.ToLower(m)
+	}
+}
+
+func sanitizeCode(s int) string {
+	switch s {
+	case 100:
+		return "100"
+	case 101:
+		return "101"
+
+	case 200:
+		return "200"
+	case 201:
+		return "201"
+	case 202:
+		return "202"
+	case 203:
+		return "203"
+	case 204:
+		return "204"
+	case 205:
+		return "205"
+	case 206:
+		return "206"
+
+	case 300:
+		return "300"
+	case 301:
+		return "301"
+	case 302:
+		return "302"
+	case 304:
+		return "304"
+	case 305:
+		return "305"
+	case 307:
+		return "307"
+
+	case 400:
+		return "400"
+	case 401:
+		return "401"
+	case 402:
+		return "402"
+	case 403:
+		return "403"
+	case 404:
+		return "404"
+	case 405:
+		return "405"
+	case 406:
+		return "406"
+	case 407:
+		return "407"
+	case 408:
+		return "408"
+	case 409:
+		return "409"
+	case 410:
+		return "410"
+	case 411:
+		return "411"
+	case 412:
+		return "412"
+	case 413:
+		return "413"
+	case 414:
+		return "414"
+	case 415:
+		return "415"
+	case 416:
+		return "416"
+	case 417:
+		return "417"
+	case 418:
+		return "418"
+
+	case 500:
+		return "500"
+	case 501:
+		return "501"
+	case 502:
+		return "502"
+	case 503:
+		return "503"
+	case 504:
+		return "504"
+	case 505:
+		return "505"
+
+	case 428:
+		return "428"
+	case 429:
+		return "429"
+	case 431:
+		return "431"
+	case 511:
+		return "511"
+
+	default:
+		return strconv.Itoa(s)
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/metric.go

@@ -0,0 +1,166 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"strings"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+const separatorByte byte = 255
+
+// A Metric models a single sample value with its meta data being exported to
+// Prometheus. Implementations of Metric in this package are Gauge, Counter,
+// Histogram, Summary, and Untyped.
+type Metric interface {
+	// Desc returns the descriptor for the Metric. This method idempotently
+	// returns the same descriptor throughout the lifetime of the
+	// Metric. The returned descriptor is immutable by contract. A Metric
+	// unable to describe itself must return an invalid descriptor (created
+	// with NewInvalidDesc).
+	Desc() *Desc
+	// Write encodes the Metric into a "Metric" Protocol Buffer data
+	// transmission object.
+	//
+	// Metric implementations must observe concurrency safety as reads of
+	// this metric may occur at any time, and any blocking occurs at the
+	// expense of total performance of rendering all registered
+	// metrics. Ideally, Metric implementations should support concurrent
+	// readers.
+	//
+	// While populating dto.Metric, it is the responsibility of the
+	// implementation to ensure validity of the Metric protobuf (like valid
+	// UTF-8 strings or syntactically valid metric and label names). It is
+	// recommended to sort labels lexicographically. (Implementers may find
+	// LabelPairSorter useful for that.) Callers of Write should still make
+	// sure of sorting if they depend on it.
+	Write(*dto.Metric) error
+	// TODO(beorn7): The original rationale of passing in a pre-allocated
+	// dto.Metric protobuf to save allocations has disappeared. The
+	// signature of this method should be changed to "Write() (*dto.Metric,
+	// error)".
+}
+
+// Opts bundles the options for creating most Metric types. Each metric
+// implementation XXX has its own XXXOpts type, but in most cases, it is just be
+// an alias of this type (which might change when the requirement arises.)
+//
+// It is mandatory to set Name and Help to a non-empty string. All other fields
+// are optional and can safely be left at their zero value.
+type Opts struct {
+	// Namespace, Subsystem, and Name are components of the fully-qualified
+	// name of the Metric (created by joining these components with
+	// "_"). Only Name is mandatory, the others merely help structuring the
+	// name. Note that the fully-qualified name of the metric must be a
+	// valid Prometheus metric name.
+	Namespace string
+	Subsystem string
+	Name      string
+
+	// Help provides information about this metric. Mandatory!
+	//
+	// Metrics with the same fully-qualified name must have the same Help
+	// string.
+	Help string
+
+	// ConstLabels are used to attach fixed labels to this metric. Metrics
+	// with the same fully-qualified name must have the same label names in
+	// their ConstLabels.
+	//
+	// Note that in most cases, labels have a value that varies during the
+	// lifetime of a process. Those labels are usually managed with a metric
+	// vector collector (like CounterVec, GaugeVec, UntypedVec). ConstLabels
+	// serve only special purposes. One is for the special case where the
+	// value of a label does not change during the lifetime of a process,
+	// e.g. if the revision of the running binary is put into a
+	// label. Another, more advanced purpose is if more than one Collector
+	// needs to collect Metrics with the same fully-qualified name. In that
+	// case, those Metrics must differ in the values of their
+	// ConstLabels. See the Collector examples.
+	//
+	// If the value of a label never changes (not even between binaries),
+	// that label most likely should not be a label at all (but part of the
+	// metric name).
+	ConstLabels Labels
+}
+
+// BuildFQName joins the given three name components by "_". Empty name
+// components are ignored. If the name parameter itself is empty, an empty
+// string is returned, no matter what. Metric implementations included in this
+// library use this function internally to generate the fully-qualified metric
+// name from the name component in their Opts. Users of the library will only
+// need this function if they implement their own Metric or instantiate a Desc
+// (with NewDesc) directly.
+func BuildFQName(namespace, subsystem, name string) string {
+	if name == "" {
+		return ""
+	}
+	switch {
+	case namespace != "" && subsystem != "":
+		return strings.Join([]string{namespace, subsystem, name}, "_")
+	case namespace != "":
+		return strings.Join([]string{namespace, name}, "_")
+	case subsystem != "":
+		return strings.Join([]string{subsystem, name}, "_")
+	}
+	return name
+}
+
+// LabelPairSorter implements sort.Interface. It is used to sort a slice of
+// dto.LabelPair pointers. This is useful for implementing the Write method of
+// custom metrics.
+type LabelPairSorter []*dto.LabelPair
+
+func (s LabelPairSorter) Len() int {
+	return len(s)
+}
+
+func (s LabelPairSorter) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s LabelPairSorter) Less(i, j int) bool {
+	return s[i].GetName() < s[j].GetName()
+}
+
+type hashSorter []uint64
+
+func (s hashSorter) Len() int {
+	return len(s)
+}
+
+func (s hashSorter) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s hashSorter) Less(i, j int) bool {
+	return s[i] < s[j]
+}
+
+type invalidMetric struct {
+	desc *Desc
+	err  error
+}
+
+// NewInvalidMetric returns a metric whose Write method always returns the
+// provided error. It is useful if a Collector finds itself unable to collect
+// a metric and wishes to report an error to the registry.
+func NewInvalidMetric(desc *Desc, err error) Metric {
+	return &invalidMetric{desc, err}
+}
+
+func (m *invalidMetric) Desc() *Desc { return m.desc }
+
+func (m *invalidMetric) Write(*dto.Metric) error { return m.err }

vendor/github.com/prometheus/client_golang/prometheus/process_collector.go

@@ -0,0 +1,142 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import "github.com/prometheus/procfs"
+
+type processCollector struct {
+	pid             int
+	collectFn       func(chan<- Metric)
+	pidFn           func() (int, error)
+	cpuTotal        Counter
+	openFDs, maxFDs Gauge
+	vsize, rss      Gauge
+	startTime       Gauge
+}
+
+// NewProcessCollector returns a collector which exports the current state of
+// process metrics including cpu, memory and file descriptor usage as well as
+// the process start time for the given process id under the given namespace.
+func NewProcessCollector(pid int, namespace string) Collector {
+	return NewProcessCollectorPIDFn(
+		func() (int, error) { return pid, nil },
+		namespace,
+	)
+}
+
+// NewProcessCollectorPIDFn returns a collector which exports the current state
+// of process metrics including cpu, memory and file descriptor usage as well
+// as the process start time under the given namespace. The given pidFn is
+// called on each collect and is used to determine the process to export
+// metrics for.
+func NewProcessCollectorPIDFn(
+	pidFn func() (int, error),
+	namespace string,
+) Collector {
+	c := processCollector{
+		pidFn:     pidFn,
+		collectFn: func(chan<- Metric) {},
+
+		cpuTotal: NewCounter(CounterOpts{
+			Namespace: namespace,
+			Name:      "process_cpu_seconds_total",
+			Help:      "Total user and system CPU time spent in seconds.",
+		}),
+		openFDs: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_open_fds",
+			Help:      "Number of open file descriptors.",
+		}),
+		maxFDs: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_max_fds",
+			Help:      "Maximum number of open file descriptors.",
+		}),
+		vsize: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_virtual_memory_bytes",
+			Help:      "Virtual memory size in bytes.",
+		}),
+		rss: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_resident_memory_bytes",
+			Help:      "Resident memory size in bytes.",
+		}),
+		startTime: NewGauge(GaugeOpts{
+			Namespace: namespace,
+			Name:      "process_start_time_seconds",
+			Help:      "Start time of the process since unix epoch in seconds.",
+		}),
+	}
+
+	// Set up process metric collection if supported by the runtime.
+	if _, err := procfs.NewStat(); err == nil {
+		c.collectFn = c.processCollect
+	}
+
+	return &c
+}
+
+// Describe returns all descriptions of the collector.
+func (c *processCollector) Describe(ch chan<- *Desc) {
+	ch <- c.cpuTotal.Desc()
+	ch <- c.openFDs.Desc()
+	ch <- c.maxFDs.Desc()
+	ch <- c.vsize.Desc()
+	ch <- c.rss.Desc()
+	ch <- c.startTime.Desc()
+}
+
+// Collect returns the current state of all metrics of the collector.
+func (c *processCollector) Collect(ch chan<- Metric) {
+	c.collectFn(ch)
+}
+
+// TODO(ts): Bring back error reporting by reverting 7faf9e7 as soon as the
+// client allows users to configure the error behavior.
+func (c *processCollector) processCollect(ch chan<- Metric) {
+	pid, err := c.pidFn()
+	if err != nil {
+		return
+	}
+
+	p, err := procfs.NewProc(pid)
+	if err != nil {
+		return
+	}
+
+	if stat, err := p.NewStat(); err == nil {
+		c.cpuTotal.Set(stat.CPUTime())
+		ch <- c.cpuTotal
+		c.vsize.Set(float64(stat.VirtualMemory()))
+		ch <- c.vsize
+		c.rss.Set(float64(stat.ResidentMemory()))
+		ch <- c.rss
+
+		if startTime, err := stat.StartTime(); err == nil {
+			c.startTime.Set(startTime)
+			ch <- c.startTime
+		}
+	}
+
+	if fds, err := p.FileDescriptorsLen(); err == nil {
+		c.openFDs.Set(float64(fds))
+		ch <- c.openFDs
+	}
+
+	if limits, err := p.NewLimits(); err == nil {
+		c.maxFDs.Set(float64(limits.OpenFiles))
+		ch <- c.maxFDs
+	}
+}

vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go

@@ -0,0 +1,201 @@
+// Copyright 2016 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Copyright (c) 2013, The Prometheus Authors
+// All rights reserved.
+//
+// Use of this source code is governed by a BSD-style license that can be found
+// in the LICENSE file.
+
+// Package promhttp contains functions to create http.Handler instances to
+// expose Prometheus metrics via HTTP. In later versions of this package, it
+// will also contain tooling to instrument instances of http.Handler and
+// http.RoundTripper.
+//
+// promhttp.Handler acts on the prometheus.DefaultGatherer. With HandlerFor,
+// you can create a handler for a custom registry or anything that implements
+// the Gatherer interface. It also allows to create handlers that act
+// differently on errors or allow to log errors.
+package promhttp
+
+import (
+	"bytes"
+	"compress/gzip"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+	"sync"
+
+	"github.com/prometheus/common/expfmt"
+
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+const (
+	contentTypeHeader     = "Content-Type"
+	contentLengthHeader   = "Content-Length"
+	contentEncodingHeader = "Content-Encoding"
+	acceptEncodingHeader  = "Accept-Encoding"
+)
+
+var bufPool sync.Pool
+
+func getBuf() *bytes.Buffer {
+	buf := bufPool.Get()
+	if buf == nil {
+		return &bytes.Buffer{}
+	}
+	return buf.(*bytes.Buffer)
+}
+
+func giveBuf(buf *bytes.Buffer) {
+	buf.Reset()
+	bufPool.Put(buf)
+}
+
+// Handler returns an HTTP handler for the prometheus.DefaultGatherer. The
+// Handler uses the default HandlerOpts, i.e. report the first error as an HTTP
+// error, no error logging, and compression if requested by the client.
+//
+// If you want to create a Handler for the DefaultGatherer with different
+// HandlerOpts, create it with HandlerFor with prometheus.DefaultGatherer and
+// your desired HandlerOpts.
+func Handler() http.Handler {
+	return HandlerFor(prometheus.DefaultGatherer, HandlerOpts{})
+}
+
+// HandlerFor returns an http.Handler for the provided Gatherer. The behavior
+// of the Handler is defined by the provided HandlerOpts.
+func HandlerFor(reg prometheus.Gatherer, opts HandlerOpts) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		mfs, err := reg.Gather()
+		if err != nil {
+			if opts.ErrorLog != nil {
+				opts.ErrorLog.Println("error gathering metrics:", err)
+			}
+			switch opts.ErrorHandling {
+			case PanicOnError:
+				panic(err)
+			case ContinueOnError:
+				if len(mfs) == 0 {
+					http.Error(w, "No metrics gathered, last error:\n\n"+err.Error(), http.StatusInternalServerError)
+					return
+				}
+			case HTTPErrorOnError:
+				http.Error(w, "An error has occurred during metrics gathering:\n\n"+err.Error(), http.StatusInternalServerError)
+				return
+			}
+		}
+
+		contentType := expfmt.Negotiate(req.Header)
+		buf := getBuf()
+		defer giveBuf(buf)
+		writer, encoding := decorateWriter(req, buf, opts.DisableCompression)
+		enc := expfmt.NewEncoder(writer, contentType)
+		var lastErr error
+		for _, mf := range mfs {
+			if err := enc.Encode(mf); err != nil {
+				lastErr = err
+				if opts.ErrorLog != nil {
+					opts.ErrorLog.Println("error encoding metric family:", err)
+				}
+				switch opts.ErrorHandling {
+				case PanicOnError:
+					panic(err)
+				case ContinueOnError:
+					// Handled later.
+				case HTTPErrorOnError:
+					http.Error(w, "An error has occurred during metrics encoding:\n\n"+err.Error(), http.StatusInternalServerError)
+					return
+				}
+			}
+		}
+		if closer, ok := writer.(io.Closer); ok {
+			closer.Close()
+		}
+		if lastErr != nil && buf.Len() == 0 {
+			http.Error(w, "No metrics encoded, last error:\n\n"+err.Error(), http.StatusInternalServerError)
+			return
+		}
+		header := w.Header()
+		header.Set(contentTypeHeader, string(contentType))
+		header.Set(contentLengthHeader, fmt.Sprint(buf.Len()))
+		if encoding != "" {
+			header.Set(contentEncodingHeader, encoding)
+		}
+		w.Write(buf.Bytes())
+		// TODO(beorn7): Consider streaming serving of metrics.
+	})
+}
+
+// HandlerErrorHandling defines how a Handler serving metrics will handle
+// errors.
+type HandlerErrorHandling int
+
+// These constants cause handlers serving metrics to behave as described if
+// errors are encountered.
+const (
+	// Serve an HTTP status code 500 upon the first error
+	// encountered. Report the error message in the body.
+	HTTPErrorOnError HandlerErrorHandling = iota
+	// Ignore errors and try to serve as many metrics as possible.  However,
+	// if no metrics can be served, serve an HTTP status code 500 and the
+	// last error message in the body. Only use this in deliberate "best
+	// effort" metrics collection scenarios. It is recommended to at least
+	// log errors (by providing an ErrorLog in HandlerOpts) to not mask
+	// errors completely.
+	ContinueOnError
+	// Panic upon the first error encountered (useful for "crash only" apps).
+	PanicOnError
+)
+
+// Logger is the minimal interface HandlerOpts needs for logging. Note that
+// log.Logger from the standard library implements this interface, and it is
+// easy to implement by custom loggers, if they don't do so already anyway.
+type Logger interface {
+	Println(v ...interface{})
+}
+
+// HandlerOpts specifies options how to serve metrics via an http.Handler. The
+// zero value of HandlerOpts is a reasonable default.
+type HandlerOpts struct {
+	// ErrorLog specifies an optional logger for errors collecting and
+	// serving metrics. If nil, errors are not logged at all.
+	ErrorLog Logger
+	// ErrorHandling defines how errors are handled. Note that errors are
+	// logged regardless of the configured ErrorHandling provided ErrorLog
+	// is not nil.
+	ErrorHandling HandlerErrorHandling
+	// If DisableCompression is true, the handler will never compress the
+	// response, even if requested by the client.
+	DisableCompression bool
+}
+
+// decorateWriter wraps a writer to handle gzip compression if requested.  It
+// returns the decorated writer and the appropriate "Content-Encoding" header
+// (which is empty if no compression is enabled).
+func decorateWriter(request *http.Request, writer io.Writer, compressionDisabled bool) (io.Writer, string) {
+	if compressionDisabled {
+		return writer, ""
+	}
+	header := request.Header.Get(acceptEncodingHeader)
+	parts := strings.Split(header, ",")
+	for _, part := range parts {
+		part := strings.TrimSpace(part)
+		if part == "gzip" || strings.HasPrefix(part, "gzip;") {
+			return gzip.NewWriter(writer), "gzip"
+		}
+	}
+	return writer, ""
+}

vendor/github.com/prometheus/client_golang/prometheus/registry.go

@@ -0,0 +1,806 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"os"
+	"sort"
+	"sync"
+
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+const (
+	// Capacity for the channel to collect metrics and descriptors.
+	capMetricChan = 1000
+	capDescChan   = 10
+)
+
+// DefaultRegisterer and DefaultGatherer are the implementations of the
+// Registerer and Gatherer interface a number of convenience functions in this
+// package act on. Initially, both variables point to the same Registry, which
+// has a process collector (see NewProcessCollector) and a Go collector (see
+// NewGoCollector) already registered. This approach to keep default instances
+// as global state mirrors the approach of other packages in the Go standard
+// library. Note that there are caveats. Change the variables with caution and
+// only if you understand the consequences. Users who want to avoid global state
+// altogether should not use the convenience function and act on custom
+// instances instead.
+var (
+	defaultRegistry              = NewRegistry()
+	DefaultRegisterer Registerer = defaultRegistry
+	DefaultGatherer   Gatherer   = defaultRegistry
+)
+
+func init() {
+	MustRegister(NewProcessCollector(os.Getpid(), ""))
+	MustRegister(NewGoCollector())
+}
+
+// NewRegistry creates a new vanilla Registry without any Collectors
+// pre-registered.
+func NewRegistry() *Registry {
+	return &Registry{
+		collectorsByID:  map[uint64]Collector{},
+		descIDs:         map[uint64]struct{}{},
+		dimHashesByName: map[string]uint64{},
+	}
+}
+
+// NewPedanticRegistry returns a registry that checks during collection if each
+// collected Metric is consistent with its reported Desc, and if the Desc has
+// actually been registered with the registry.
+//
+// Usually, a Registry will be happy as long as the union of all collected
+// Metrics is consistent and valid even if some metrics are not consistent with
+// their own Desc or a Desc provided by their registered Collector. Well-behaved
+// Collectors and Metrics will only provide consistent Descs. This Registry is
+// useful to test the implementation of Collectors and Metrics.
+func NewPedanticRegistry() *Registry {
+	r := NewRegistry()
+	r.pedanticChecksEnabled = true
+	return r
+}
+
+// Registerer is the interface for the part of a registry in charge of
+// registering and unregistering. Users of custom registries should use
+// Registerer as type for registration purposes (rather then the Registry type
+// directly). In that way, they are free to use custom Registerer implementation
+// (e.g. for testing purposes).
+type Registerer interface {
+	// Register registers a new Collector to be included in metrics
+	// collection. It returns an error if the descriptors provided by the
+	// Collector are invalid or if they — in combination with descriptors of
+	// already registered Collectors — do not fulfill the consistency and
+	// uniqueness criteria described in the documentation of metric.Desc.
+	//
+	// If the provided Collector is equal to a Collector already registered
+	// (which includes the case of re-registering the same Collector), the
+	// returned error is an instance of AlreadyRegisteredError, which
+	// contains the previously registered Collector.
+	//
+	// It is in general not safe to register the same Collector multiple
+	// times concurrently.
+	Register(Collector) error
+	// MustRegister works like Register but registers any number of
+	// Collectors and panics upon the first registration that causes an
+	// error.
+	MustRegister(...Collector)
+	// Unregister unregisters the Collector that equals the Collector passed
+	// in as an argument.  (Two Collectors are considered equal if their
+	// Describe method yields the same set of descriptors.) The function
+	// returns whether a Collector was unregistered.
+	//
+	// Note that even after unregistering, it will not be possible to
+	// register a new Collector that is inconsistent with the unregistered
+	// Collector, e.g. a Collector collecting metrics with the same name but
+	// a different help string. The rationale here is that the same registry
+	// instance must only collect consistent metrics throughout its
+	// lifetime.
+	Unregister(Collector) bool
+}
+
+// Gatherer is the interface for the part of a registry in charge of gathering
+// the collected metrics into a number of MetricFamilies. The Gatherer interface
+// comes with the same general implication as described for the Registerer
+// interface.
+type Gatherer interface {
+	// Gather calls the Collect method of the registered Collectors and then
+	// gathers the collected metrics into a lexicographically sorted slice
+	// of MetricFamily protobufs. Even if an error occurs, Gather attempts
+	// to gather as many metrics as possible. Hence, if a non-nil error is
+	// returned, the returned MetricFamily slice could be nil (in case of a
+	// fatal error that prevented any meaningful metric collection) or
+	// contain a number of MetricFamily protobufs, some of which might be
+	// incomplete, and some might be missing altogether. The returned error
+	// (which might be a MultiError) explains the details. In scenarios
+	// where complete collection is critical, the returned MetricFamily
+	// protobufs should be disregarded if the returned error is non-nil.
+	Gather() ([]*dto.MetricFamily, error)
+}
+
+// Register registers the provided Collector with the DefaultRegisterer.
+//
+// Register is a shortcut for DefaultRegisterer.Register(c). See there for more
+// details.
+func Register(c Collector) error {
+	return DefaultRegisterer.Register(c)
+}
+
+// MustRegister registers the provided Collectors with the DefaultRegisterer and
+// panics if any error occurs.
+//
+// MustRegister is a shortcut for DefaultRegisterer.MustRegister(cs...). See
+// there for more details.
+func MustRegister(cs ...Collector) {
+	DefaultRegisterer.MustRegister(cs...)
+}
+
+// RegisterOrGet registers the provided Collector with the DefaultRegisterer and
+// returns the Collector, unless an equal Collector was registered before, in
+// which case that Collector is returned.
+//
+// Deprecated: RegisterOrGet is merely a convenience function for the
+// implementation as described in the documentation for
+// AlreadyRegisteredError. As the use case is relatively rare, this function
+// will be removed in a future version of this package to clean up the
+// namespace.
+func RegisterOrGet(c Collector) (Collector, error) {
+	if err := Register(c); err != nil {
+		if are, ok := err.(AlreadyRegisteredError); ok {
+			return are.ExistingCollector, nil
+		}
+		return nil, err
+	}
+	return c, nil
+}
+
+// MustRegisterOrGet behaves like RegisterOrGet but panics instead of returning
+// an error.
+//
+// Deprecated: This is deprecated for the same reason RegisterOrGet is. See
+// there for details.
+func MustRegisterOrGet(c Collector) Collector {
+	c, err := RegisterOrGet(c)
+	if err != nil {
+		panic(err)
+	}
+	return c
+}
+
+// Unregister removes the registration of the provided Collector from the
+// DefaultRegisterer.
+//
+// Unregister is a shortcut for DefaultRegisterer.Unregister(c). See there for
+// more details.
+func Unregister(c Collector) bool {
+	return DefaultRegisterer.Unregister(c)
+}
+
+// GathererFunc turns a function into a Gatherer.
+type GathererFunc func() ([]*dto.MetricFamily, error)
+
+// Gather implements Gatherer.
+func (gf GathererFunc) Gather() ([]*dto.MetricFamily, error) {
+	return gf()
+}
+
+// SetMetricFamilyInjectionHook replaces the DefaultGatherer with one that
+// gathers from the previous DefaultGatherers but then merges the MetricFamily
+// protobufs returned from the provided hook function with the MetricFamily
+// protobufs returned from the original DefaultGatherer.
+//
+// Deprecated: This function manipulates the DefaultGatherer variable. Consider
+// the implications, i.e. don't do this concurrently with any uses of the
+// DefaultGatherer. In the rare cases where you need to inject MetricFamily
+// protobufs directly, it is recommended to use a custom Registry and combine it
+// with a custom Gatherer using the Gatherers type (see
+// there). SetMetricFamilyInjectionHook only exists for compatibility reasons
+// with previous versions of this package.
+func SetMetricFamilyInjectionHook(hook func() []*dto.MetricFamily) {
+	DefaultGatherer = Gatherers{
+		DefaultGatherer,
+		GathererFunc(func() ([]*dto.MetricFamily, error) { return hook(), nil }),
+	}
+}
+
+// AlreadyRegisteredError is returned by the Register method if the Collector to
+// be registered has already been registered before, or a different Collector
+// that collects the same metrics has been registered before. Registration fails
+// in that case, but you can detect from the kind of error what has
+// happened. The error contains fields for the existing Collector and the
+// (rejected) new Collector that equals the existing one. This can be used to
+// find out if an equal Collector has been registered before and switch over to
+// using the old one, as demonstrated in the example.
+type AlreadyRegisteredError struct {
+	ExistingCollector, NewCollector Collector
+}
+
+func (err AlreadyRegisteredError) Error() string {
+	return "duplicate metrics collector registration attempted"
+}
+
+// MultiError is a slice of errors implementing the error interface. It is used
+// by a Gatherer to report multiple errors during MetricFamily gathering.
+type MultiError []error
+
+func (errs MultiError) Error() string {
+	if len(errs) == 0 {
+		return ""
+	}
+	buf := &bytes.Buffer{}
+	fmt.Fprintf(buf, "%d error(s) occurred:", len(errs))
+	for _, err := range errs {
+		fmt.Fprintf(buf, "\n* %s", err)
+	}
+	return buf.String()
+}
+
+// MaybeUnwrap returns nil if len(errs) is 0. It returns the first and only
+// contained error as error if len(errs is 1). In all other cases, it returns
+// the MultiError directly. This is helpful for returning a MultiError in a way
+// that only uses the MultiError if needed.
+func (errs MultiError) MaybeUnwrap() error {
+	switch len(errs) {
+	case 0:
+		return nil
+	case 1:
+		return errs[0]
+	default:
+		return errs
+	}
+}
+
+// Registry registers Prometheus collectors, collects their metrics, and gathers
+// them into MetricFamilies for exposition. It implements both Registerer and
+// Gatherer. The zero value is not usable. Create instances with NewRegistry or
+// NewPedanticRegistry.
+type Registry struct {
+	mtx                   sync.RWMutex
+	collectorsByID        map[uint64]Collector // ID is a hash of the descIDs.
+	descIDs               map[uint64]struct{}
+	dimHashesByName       map[string]uint64
+	pedanticChecksEnabled bool
+}
+
+// Register implements Registerer.
+func (r *Registry) Register(c Collector) error {
+	var (
+		descChan           = make(chan *Desc, capDescChan)
+		newDescIDs         = map[uint64]struct{}{}
+		newDimHashesByName = map[string]uint64{}
+		collectorID        uint64 // Just a sum of all desc IDs.
+		duplicateDescErr   error
+	)
+	go func() {
+		c.Describe(descChan)
+		close(descChan)
+	}()
+	r.mtx.Lock()
+	defer r.mtx.Unlock()
+	// Coduct various tests...
+	for desc := range descChan {
+
+		// Is the descriptor valid at all?
+		if desc.err != nil {
+			return fmt.Errorf("descriptor %s is invalid: %s", desc, desc.err)
+		}
+
+		// Is the descID unique?
+		// (In other words: Is the fqName + constLabel combination unique?)
+		if _, exists := r.descIDs[desc.id]; exists {
+			duplicateDescErr = fmt.Errorf("descriptor %s already exists with the same fully-qualified name and const label values", desc)
+		}
+		// If it is not a duplicate desc in this collector, add it to
+		// the collectorID.  (We allow duplicate descs within the same
+		// collector, but their existence must be a no-op.)
+		if _, exists := newDescIDs[desc.id]; !exists {
+			newDescIDs[desc.id] = struct{}{}
+			collectorID += desc.id
+		}
+
+		// Are all the label names and the help string consistent with
+		// previous descriptors of the same name?
+		// First check existing descriptors...
+		if dimHash, exists := r.dimHashesByName[desc.fqName]; exists {
+			if dimHash != desc.dimHash {
+				return fmt.Errorf("a previously registered descriptor with the same fully-qualified name as %s has different label names or a different help string", desc)
+			}
+		} else {
+			// ...then check the new descriptors already seen.
+			if dimHash, exists := newDimHashesByName[desc.fqName]; exists {
+				if dimHash != desc.dimHash {
+					return fmt.Errorf("descriptors reported by collector have inconsistent label names or help strings for the same fully-qualified name, offender is %s", desc)
+				}
+			} else {
+				newDimHashesByName[desc.fqName] = desc.dimHash
+			}
+		}
+	}
+	// Did anything happen at all?
+	if len(newDescIDs) == 0 {
+		return errors.New("collector has no descriptors")
+	}
+	if existing, exists := r.collectorsByID[collectorID]; exists {
+		return AlreadyRegisteredError{
+			ExistingCollector: existing,
+			NewCollector:      c,
+		}
+	}
+	// If the collectorID is new, but at least one of the descs existed
+	// before, we are in trouble.
+	if duplicateDescErr != nil {
+		return duplicateDescErr
+	}
+
+	// Only after all tests have passed, actually register.
+	r.collectorsByID[collectorID] = c
+	for hash := range newDescIDs {
+		r.descIDs[hash] = struct{}{}
+	}
+	for name, dimHash := range newDimHashesByName {
+		r.dimHashesByName[name] = dimHash
+	}
+	return nil
+}
+
+// Unregister implements Registerer.
+func (r *Registry) Unregister(c Collector) bool {
+	var (
+		descChan    = make(chan *Desc, capDescChan)
+		descIDs     = map[uint64]struct{}{}
+		collectorID uint64 // Just a sum of the desc IDs.
+	)
+	go func() {
+		c.Describe(descChan)
+		close(descChan)
+	}()
+	for desc := range descChan {
+		if _, exists := descIDs[desc.id]; !exists {
+			collectorID += desc.id
+			descIDs[desc.id] = struct{}{}
+		}
+	}
+
+	r.mtx.RLock()
+	if _, exists := r.collectorsByID[collectorID]; !exists {
+		r.mtx.RUnlock()
+		return false
+	}
+	r.mtx.RUnlock()
+
+	r.mtx.Lock()
+	defer r.mtx.Unlock()
+
+	delete(r.collectorsByID, collectorID)
+	for id := range descIDs {
+		delete(r.descIDs, id)
+	}
+	// dimHashesByName is left untouched as those must be consistent
+	// throughout the lifetime of a program.
+	return true
+}
+
+// MustRegister implements Registerer.
+func (r *Registry) MustRegister(cs ...Collector) {
+	for _, c := range cs {
+		if err := r.Register(c); err != nil {
+			panic(err)
+		}
+	}
+}
+
+// Gather implements Gatherer.
+func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
+	var (
+		metricChan        = make(chan Metric, capMetricChan)
+		metricHashes      = map[uint64]struct{}{}
+		dimHashes         = map[string]uint64{}
+		wg                sync.WaitGroup
+		errs              MultiError          // The collected errors to return in the end.
+		registeredDescIDs map[uint64]struct{} // Only used for pedantic checks
+	)
+
+	r.mtx.RLock()
+	metricFamiliesByName := make(map[string]*dto.MetricFamily, len(r.dimHashesByName))
+
+	// Scatter.
+	// (Collectors could be complex and slow, so we call them all at once.)
+	wg.Add(len(r.collectorsByID))
+	go func() {
+		wg.Wait()
+		close(metricChan)
+	}()
+	for _, collector := range r.collectorsByID {
+		go func(collector Collector) {
+			defer wg.Done()
+			collector.Collect(metricChan)
+		}(collector)
+	}
+
+	// In case pedantic checks are enabled, we have to copy the map before
+	// giving up the RLock.
+	if r.pedanticChecksEnabled {
+		registeredDescIDs = make(map[uint64]struct{}, len(r.descIDs))
+		for id := range r.descIDs {
+			registeredDescIDs[id] = struct{}{}
+		}
+	}
+
+	r.mtx.RUnlock()
+
+	// Drain metricChan in case of premature return.
+	defer func() {
+		for _ = range metricChan {
+		}
+	}()
+
+	// Gather.
+	for metric := range metricChan {
+		// This could be done concurrently, too, but it required locking
+		// of metricFamiliesByName (and of metricHashes if checks are
+		// enabled). Most likely not worth it.
+		desc := metric.Desc()
+		dtoMetric := &dto.Metric{}
+		if err := metric.Write(dtoMetric); err != nil {
+			errs = append(errs, fmt.Errorf(
+				"error collecting metric %v: %s", desc, err,
+			))
+			continue
+		}
+		metricFamily, ok := metricFamiliesByName[desc.fqName]
+		if ok {
+			if metricFamily.GetHelp() != desc.help {
+				errs = append(errs, fmt.Errorf(
+					"collected metric %s %s has help %q but should have %q",
+					desc.fqName, dtoMetric, desc.help, metricFamily.GetHelp(),
+				))
+				continue
+			}
+			// TODO(beorn7): Simplify switch once Desc has type.
+			switch metricFamily.GetType() {
+			case dto.MetricType_COUNTER:
+				if dtoMetric.Counter == nil {
+					errs = append(errs, fmt.Errorf(
+						"collected metric %s %s should be a Counter",
+						desc.fqName, dtoMetric,
+					))
+					continue
+				}
+			case dto.MetricType_GAUGE:
+				if dtoMetric.Gauge == nil {
+					errs = append(errs, fmt.Errorf(
+						"collected metric %s %s should be a Gauge",
+						desc.fqName, dtoMetric,
+					))
+					continue
+				}
+			case dto.MetricType_SUMMARY:
+				if dtoMetric.Summary == nil {
+					errs = append(errs, fmt.Errorf(
+						"collected metric %s %s should be a Summary",
+						desc.fqName, dtoMetric,
+					))
+					continue
+				}
+			case dto.MetricType_UNTYPED:
+				if dtoMetric.Untyped == nil {
+					errs = append(errs, fmt.Errorf(
+						"collected metric %s %s should be Untyped",
+						desc.fqName, dtoMetric,
+					))
+					continue
+				}
+			case dto.MetricType_HISTOGRAM:
+				if dtoMetric.Histogram == nil {
+					errs = append(errs, fmt.Errorf(
+						"collected metric %s %s should be a Histogram",
+						desc.fqName, dtoMetric,
+					))
+					continue
+				}
+			default:
+				panic("encountered MetricFamily with invalid type")
+			}
+		} else {
+			metricFamily = &dto.MetricFamily{}
+			metricFamily.Name = proto.String(desc.fqName)
+			metricFamily.Help = proto.String(desc.help)
+			// TODO(beorn7): Simplify switch once Desc has type.
+			switch {
+			case dtoMetric.Gauge != nil:
+				metricFamily.Type = dto.MetricType_GAUGE.Enum()
+			case dtoMetric.Counter != nil:
+				metricFamily.Type = dto.MetricType_COUNTER.Enum()
+			case dtoMetric.Summary != nil:
+				metricFamily.Type = dto.MetricType_SUMMARY.Enum()
+			case dtoMetric.Untyped != nil:
+				metricFamily.Type = dto.MetricType_UNTYPED.Enum()
+			case dtoMetric.Histogram != nil:
+				metricFamily.Type = dto.MetricType_HISTOGRAM.Enum()
+			default:
+				errs = append(errs, fmt.Errorf(
+					"empty metric collected: %s", dtoMetric,
+				))
+				continue
+			}
+			metricFamiliesByName[desc.fqName] = metricFamily
+		}
+		if err := checkMetricConsistency(metricFamily, dtoMetric, metricHashes, dimHashes); err != nil {
+			errs = append(errs, err)
+			continue
+		}
+		if r.pedanticChecksEnabled {
+			// Is the desc registered at all?
+			if _, exist := registeredDescIDs[desc.id]; !exist {
+				errs = append(errs, fmt.Errorf(
+					"collected metric %s %s with unregistered descriptor %s",
+					metricFamily.GetName(), dtoMetric, desc,
+				))
+				continue
+			}
+			if err := checkDescConsistency(metricFamily, dtoMetric, desc); err != nil {
+				errs = append(errs, err)
+				continue
+			}
+		}
+		metricFamily.Metric = append(metricFamily.Metric, dtoMetric)
+	}
+	return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
+}
+
+// Gatherers is a slice of Gatherer instances that implements the Gatherer
+// interface itself. Its Gather method calls Gather on all Gatherers in the
+// slice in order and returns the merged results. Errors returned from the
+// Gather calles are all returned in a flattened MultiError. Duplicate and
+// inconsistent Metrics are skipped (first occurrence in slice order wins) and
+// reported in the returned error.
+//
+// Gatherers can be used to merge the Gather results from multiple
+// Registries. It also provides a way to directly inject existing MetricFamily
+// protobufs into the gathering by creating a custom Gatherer with a Gather
+// method that simply returns the existing MetricFamily protobufs. Note that no
+// registration is involved (in contrast to Collector registration), so
+// obviously registration-time checks cannot happen. Any inconsistencies between
+// the gathered MetricFamilies are reported as errors by the Gather method, and
+// inconsistent Metrics are dropped. Invalid parts of the MetricFamilies
+// (e.g. syntactically invalid metric or label names) will go undetected.
+type Gatherers []Gatherer
+
+// Gather implements Gatherer.
+func (gs Gatherers) Gather() ([]*dto.MetricFamily, error) {
+	var (
+		metricFamiliesByName = map[string]*dto.MetricFamily{}
+		metricHashes         = map[uint64]struct{}{}
+		dimHashes            = map[string]uint64{}
+		errs                 MultiError // The collected errors to return in the end.
+	)
+
+	for i, g := range gs {
+		mfs, err := g.Gather()
+		if err != nil {
+			if multiErr, ok := err.(MultiError); ok {
+				for _, err := range multiErr {
+					errs = append(errs, fmt.Errorf("[from Gatherer #%d] %s", i+1, err))
+				}
+			} else {
+				errs = append(errs, fmt.Errorf("[from Gatherer #%d] %s", i+1, err))
+			}
+		}
+		for _, mf := range mfs {
+			existingMF, exists := metricFamiliesByName[mf.GetName()]
+			if exists {
+				if existingMF.GetHelp() != mf.GetHelp() {
+					errs = append(errs, fmt.Errorf(
+						"gathered metric family %s has help %q but should have %q",
+						mf.GetName(), mf.GetHelp(), existingMF.GetHelp(),
+					))
+					continue
+				}
+				if existingMF.GetType() != mf.GetType() {
+					errs = append(errs, fmt.Errorf(
+						"gathered metric family %s has type %s but should have %s",
+						mf.GetName(), mf.GetType(), existingMF.GetType(),
+					))
+					continue
+				}
+			} else {
+				existingMF = &dto.MetricFamily{}
+				existingMF.Name = mf.Name
+				existingMF.Help = mf.Help
+				existingMF.Type = mf.Type
+				metricFamiliesByName[mf.GetName()] = existingMF
+			}
+			for _, m := range mf.Metric {
+				if err := checkMetricConsistency(existingMF, m, metricHashes, dimHashes); err != nil {
+					errs = append(errs, err)
+					continue
+				}
+				existingMF.Metric = append(existingMF.Metric, m)
+			}
+		}
+	}
+	return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
+}
+
+// metricSorter is a sortable slice of *dto.Metric.
+type metricSorter []*dto.Metric
+
+func (s metricSorter) Len() int {
+	return len(s)
+}
+
+func (s metricSorter) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s metricSorter) Less(i, j int) bool {
+	if len(s[i].Label) != len(s[j].Label) {
+		// This should not happen. The metrics are
+		// inconsistent. However, we have to deal with the fact, as
+		// people might use custom collectors or metric family injection
+		// to create inconsistent metrics. So let's simply compare the
+		// number of labels in this case. That will still yield
+		// reproducible sorting.
+		return len(s[i].Label) < len(s[j].Label)
+	}
+	for n, lp := range s[i].Label {
+		vi := lp.GetValue()
+		vj := s[j].Label[n].GetValue()
+		if vi != vj {
+			return vi < vj
+		}
+	}
+
+	// We should never arrive here. Multiple metrics with the same
+	// label set in the same scrape will lead to undefined ingestion
+	// behavior. However, as above, we have to provide stable sorting
+	// here, even for inconsistent metrics. So sort equal metrics
+	// by their timestamp, with missing timestamps (implying "now")
+	// coming last.
+	if s[i].TimestampMs == nil {
+		return false
+	}
+	if s[j].TimestampMs == nil {
+		return true
+	}
+	return s[i].GetTimestampMs() < s[j].GetTimestampMs()
+}
+
+// normalizeMetricFamilies returns a MetricFamily slice whith empty
+// MetricFamilies pruned and the remaining MetricFamilies sorted by name within
+// the slice, with the contained Metrics sorted within each MetricFamily.
+func normalizeMetricFamilies(metricFamiliesByName map[string]*dto.MetricFamily) []*dto.MetricFamily {
+	for _, mf := range metricFamiliesByName {
+		sort.Sort(metricSorter(mf.Metric))
+	}
+	names := make([]string, 0, len(metricFamiliesByName))
+	for name, mf := range metricFamiliesByName {
+		if len(mf.Metric) > 0 {
+			names = append(names, name)
+		}
+	}
+	sort.Strings(names)
+	result := make([]*dto.MetricFamily, 0, len(names))
+	for _, name := range names {
+		result = append(result, metricFamiliesByName[name])
+	}
+	return result
+}
+
+// checkMetricConsistency checks if the provided Metric is consistent with the
+// provided MetricFamily. It also hashed the Metric labels and the MetricFamily
+// name. If the resulting hash is alread in the provided metricHashes, an error
+// is returned. If not, it is added to metricHashes. The provided dimHashes maps
+// MetricFamily names to their dimHash (hashed sorted label names). If dimHashes
+// doesn't yet contain a hash for the provided MetricFamily, it is
+// added. Otherwise, an error is returned if the existing dimHashes in not equal
+// the calculated dimHash.
+func checkMetricConsistency(
+	metricFamily *dto.MetricFamily,
+	dtoMetric *dto.Metric,
+	metricHashes map[uint64]struct{},
+	dimHashes map[string]uint64,
+) error {
+	// Type consistency with metric family.
+	if metricFamily.GetType() == dto.MetricType_GAUGE && dtoMetric.Gauge == nil ||
+		metricFamily.GetType() == dto.MetricType_COUNTER && dtoMetric.Counter == nil ||
+		metricFamily.GetType() == dto.MetricType_SUMMARY && dtoMetric.Summary == nil ||
+		metricFamily.GetType() == dto.MetricType_HISTOGRAM && dtoMetric.Histogram == nil ||
+		metricFamily.GetType() == dto.MetricType_UNTYPED && dtoMetric.Untyped == nil {
+		return fmt.Errorf(
+			"collected metric %s %s is not a %s",
+			metricFamily.GetName(), dtoMetric, metricFamily.GetType(),
+		)
+	}
+
+	// Is the metric unique (i.e. no other metric with the same name and the same label values)?
+	h := hashNew()
+	h = hashAdd(h, metricFamily.GetName())
+	h = hashAddByte(h, separatorByte)
+	dh := hashNew()
+	// Make sure label pairs are sorted. We depend on it for the consistency
+	// check.
+	sort.Sort(LabelPairSorter(dtoMetric.Label))
+	for _, lp := range dtoMetric.Label {
+		h = hashAdd(h, lp.GetValue())
+		h = hashAddByte(h, separatorByte)
+		dh = hashAdd(dh, lp.GetName())
+		dh = hashAddByte(dh, separatorByte)
+	}
+	if _, exists := metricHashes[h]; exists {
+		return fmt.Errorf(
+			"collected metric %s %s was collected before with the same name and label values",
+			metricFamily.GetName(), dtoMetric,
+		)
+	}
+	if dimHash, ok := dimHashes[metricFamily.GetName()]; ok {
+		if dimHash != dh {
+			return fmt.Errorf(
+				"collected metric %s %s has label dimensions inconsistent with previously collected metrics in the same metric family",
+				metricFamily.GetName(), dtoMetric,
+			)
+		}
+	} else {
+		dimHashes[metricFamily.GetName()] = dh
+	}
+	metricHashes[h] = struct{}{}
+	return nil
+}
+
+func checkDescConsistency(
+	metricFamily *dto.MetricFamily,
+	dtoMetric *dto.Metric,
+	desc *Desc,
+) error {
+	// Desc help consistency with metric family help.
+	if metricFamily.GetHelp() != desc.help {
+		return fmt.Errorf(
+			"collected metric %s %s has help %q but should have %q",
+			metricFamily.GetName(), dtoMetric, metricFamily.GetHelp(), desc.help,
+		)
+	}
+
+	// Is the desc consistent with the content of the metric?
+	lpsFromDesc := make([]*dto.LabelPair, 0, len(dtoMetric.Label))
+	lpsFromDesc = append(lpsFromDesc, desc.constLabelPairs...)
+	for _, l := range desc.variableLabels {
+		lpsFromDesc = append(lpsFromDesc, &dto.LabelPair{
+			Name: proto.String(l),
+		})
+	}
+	if len(lpsFromDesc) != len(dtoMetric.Label) {
+		return fmt.Errorf(
+			"labels in collected metric %s %s are inconsistent with descriptor %s",
+			metricFamily.GetName(), dtoMetric, desc,
+		)
+	}
+	sort.Sort(LabelPairSorter(lpsFromDesc))
+	for i, lpFromDesc := range lpsFromDesc {
+		lpFromMetric := dtoMetric.Label[i]
+		if lpFromDesc.GetName() != lpFromMetric.GetName() ||
+			lpFromDesc.Value != nil && lpFromDesc.GetValue() != lpFromMetric.GetValue() {
+			return fmt.Errorf(
+				"labels in collected metric %s %s are inconsistent with descriptor %s",
+				metricFamily.GetName(), dtoMetric, desc,
+			)
+		}
+	}
+	return nil
+}

vendor/github.com/prometheus/client_golang/prometheus/summary.go

@@ -0,0 +1,534 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"fmt"
+	"math"
+	"sort"
+	"sync"
+	"time"
+
+	"github.com/beorn7/perks/quantile"
+	"github.com/golang/protobuf/proto"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// quantileLabel is used for the label that defines the quantile in a
+// summary.
+const quantileLabel = "quantile"
+
+// A Summary captures individual observations from an event or sample stream and
+// summarizes them in a manner similar to traditional summary statistics: 1. sum
+// of observations, 2. observation count, 3. rank estimations.
+//
+// A typical use-case is the observation of request latencies. By default, a
+// Summary provides the median, the 90th and the 99th percentile of the latency
+// as rank estimations.
+//
+// Note that the rank estimations cannot be aggregated in a meaningful way with
+// the Prometheus query language (i.e. you cannot average or add them). If you
+// need aggregatable quantiles (e.g. you want the 99th percentile latency of all
+// queries served across all instances of a service), consider the Histogram
+// metric type. See the Prometheus documentation for more details.
+//
+// To create Summary instances, use NewSummary.
+type Summary interface {
+	Metric
+	Collector
+
+	// Observe adds a single observation to the summary.
+	Observe(float64)
+}
+
+// DefObjectives are the default Summary quantile values.
+var (
+	DefObjectives = map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001}
+
+	errQuantileLabelNotAllowed = fmt.Errorf(
+		"%q is not allowed as label name in summaries", quantileLabel,
+	)
+)
+
+// Default values for SummaryOpts.
+const (
+	// DefMaxAge is the default duration for which observations stay
+	// relevant.
+	DefMaxAge time.Duration = 10 * time.Minute
+	// DefAgeBuckets is the default number of buckets used to calculate the
+	// age of observations.
+	DefAgeBuckets = 5
+	// DefBufCap is the standard buffer size for collecting Summary observations.
+	DefBufCap = 500
+)
+
+// SummaryOpts bundles the options for creating a Summary metric. It is
+// mandatory to set Name and Help to a non-empty string. All other fields are
+// optional and can safely be left at their zero value.
+type SummaryOpts struct {
+	// Namespace, Subsystem, and Name are components of the fully-qualified
+	// name of the Summary (created by joining these components with
+	// "_"). Only Name is mandatory, the others merely help structuring the
+	// name. Note that the fully-qualified name of the Summary must be a
+	// valid Prometheus metric name.
+	Namespace string
+	Subsystem string
+	Name      string
+
+	// Help provides information about this Summary. Mandatory!
+	//
+	// Metrics with the same fully-qualified name must have the same Help
+	// string.
+	Help string
+
+	// ConstLabels are used to attach fixed labels to this
+	// Summary. Summaries with the same fully-qualified name must have the
+	// same label names in their ConstLabels.
+	//
+	// Note that in most cases, labels have a value that varies during the
+	// lifetime of a process. Those labels are usually managed with a
+	// SummaryVec. ConstLabels serve only special purposes. One is for the
+	// special case where the value of a label does not change during the
+	// lifetime of a process, e.g. if the revision of the running binary is
+	// put into a label. Another, more advanced purpose is if more than one
+	// Collector needs to collect Summaries with the same fully-qualified
+	// name. In that case, those Summaries must differ in the values of
+	// their ConstLabels. See the Collector examples.
+	//
+	// If the value of a label never changes (not even between binaries),
+	// that label most likely should not be a label at all (but part of the
+	// metric name).
+	ConstLabels Labels
+
+	// Objectives defines the quantile rank estimates with their respective
+	// absolute error. If Objectives[q] = e, then the value reported
+	// for q will be the φ-quantile value for some φ between q-e and q+e.
+	// The default value is DefObjectives.
+	Objectives map[float64]float64
+
+	// MaxAge defines the duration for which an observation stays relevant
+	// for the summary. Must be positive. The default value is DefMaxAge.
+	MaxAge time.Duration
+
+	// AgeBuckets is the number of buckets used to exclude observations that
+	// are older than MaxAge from the summary. A higher number has a
+	// resource penalty, so only increase it if the higher resolution is
+	// really required. For very high observation rates, you might want to
+	// reduce the number of age buckets. With only one age bucket, you will
+	// effectively see a complete reset of the summary each time MaxAge has
+	// passed. The default value is DefAgeBuckets.
+	AgeBuckets uint32
+
+	// BufCap defines the default sample stream buffer size.  The default
+	// value of DefBufCap should suffice for most uses. If there is a need
+	// to increase the value, a multiple of 500 is recommended (because that
+	// is the internal buffer size of the underlying package
+	// "github.com/bmizerany/perks/quantile").
+	BufCap uint32
+}
+
+// Great fuck-up with the sliding-window decay algorithm... The Merge method of
+// perk/quantile is actually not working as advertised - and it might be
+// unfixable, as the underlying algorithm is apparently not capable of merging
+// summaries in the first place. To avoid using Merge, we are currently adding
+// observations to _each_ age bucket, i.e. the effort to add a sample is
+// essentially multiplied by the number of age buckets. When rotating age
+// buckets, we empty the previous head stream. On scrape time, we simply take
+// the quantiles from the head stream (no merging required). Result: More effort
+// on observation time, less effort on scrape time, which is exactly the
+// opposite of what we try to accomplish, but at least the results are correct.
+//
+// The quite elegant previous contraption to merge the age buckets efficiently
+// on scrape time (see code up commit 6b9530d72ea715f0ba612c0120e6e09fbf1d49d0)
+// can't be used anymore.
+
+// NewSummary creates a new Summary based on the provided SummaryOpts.
+func NewSummary(opts SummaryOpts) Summary {
+	return newSummary(
+		NewDesc(
+			BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+			opts.Help,
+			nil,
+			opts.ConstLabels,
+		),
+		opts,
+	)
+}
+
+func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
+	if len(desc.variableLabels) != len(labelValues) {
+		panic(errInconsistentCardinality)
+	}
+
+	for _, n := range desc.variableLabels {
+		if n == quantileLabel {
+			panic(errQuantileLabelNotAllowed)
+		}
+	}
+	for _, lp := range desc.constLabelPairs {
+		if lp.GetName() == quantileLabel {
+			panic(errQuantileLabelNotAllowed)
+		}
+	}
+
+	if len(opts.Objectives) == 0 {
+		opts.Objectives = DefObjectives
+	}
+
+	if opts.MaxAge < 0 {
+		panic(fmt.Errorf("illegal max age MaxAge=%v", opts.MaxAge))
+	}
+	if opts.MaxAge == 0 {
+		opts.MaxAge = DefMaxAge
+	}
+
+	if opts.AgeBuckets == 0 {
+		opts.AgeBuckets = DefAgeBuckets
+	}
+
+	if opts.BufCap == 0 {
+		opts.BufCap = DefBufCap
+	}
+
+	s := &summary{
+		desc: desc,
+
+		objectives:       opts.Objectives,
+		sortedObjectives: make([]float64, 0, len(opts.Objectives)),
+
+		labelPairs: makeLabelPairs(desc, labelValues),
+
+		hotBuf:         make([]float64, 0, opts.BufCap),
+		coldBuf:        make([]float64, 0, opts.BufCap),
+		streamDuration: opts.MaxAge / time.Duration(opts.AgeBuckets),
+	}
+	s.headStreamExpTime = time.Now().Add(s.streamDuration)
+	s.hotBufExpTime = s.headStreamExpTime
+
+	for i := uint32(0); i < opts.AgeBuckets; i++ {
+		s.streams = append(s.streams, s.newStream())
+	}
+	s.headStream = s.streams[0]
+
+	for qu := range s.objectives {
+		s.sortedObjectives = append(s.sortedObjectives, qu)
+	}
+	sort.Float64s(s.sortedObjectives)
+
+	s.init(s) // Init self-collection.
+	return s
+}
+
+type summary struct {
+	selfCollector
+
+	bufMtx sync.Mutex // Protects hotBuf and hotBufExpTime.
+	mtx    sync.Mutex // Protects every other moving part.
+	// Lock bufMtx before mtx if both are needed.
+
+	desc *Desc
+
+	objectives       map[float64]float64
+	sortedObjectives []float64
+
+	labelPairs []*dto.LabelPair
+
+	sum float64
+	cnt uint64
+
+	hotBuf, coldBuf []float64
+
+	streams                          []*quantile.Stream
+	streamDuration                   time.Duration
+	headStream                       *quantile.Stream
+	headStreamIdx                    int
+	headStreamExpTime, hotBufExpTime time.Time
+}
+
+func (s *summary) Desc() *Desc {
+	return s.desc
+}
+
+func (s *summary) Observe(v float64) {
+	s.bufMtx.Lock()
+	defer s.bufMtx.Unlock()
+
+	now := time.Now()
+	if now.After(s.hotBufExpTime) {
+		s.asyncFlush(now)
+	}
+	s.hotBuf = append(s.hotBuf, v)
+	if len(s.hotBuf) == cap(s.hotBuf) {
+		s.asyncFlush(now)
+	}
+}
+
+func (s *summary) Write(out *dto.Metric) error {
+	sum := &dto.Summary{}
+	qs := make([]*dto.Quantile, 0, len(s.objectives))
+
+	s.bufMtx.Lock()
+	s.mtx.Lock()
+	// Swap bufs even if hotBuf is empty to set new hotBufExpTime.
+	s.swapBufs(time.Now())
+	s.bufMtx.Unlock()
+
+	s.flushColdBuf()
+	sum.SampleCount = proto.Uint64(s.cnt)
+	sum.SampleSum = proto.Float64(s.sum)
+
+	for _, rank := range s.sortedObjectives {
+		var q float64
+		if s.headStream.Count() == 0 {
+			q = math.NaN()
+		} else {
+			q = s.headStream.Query(rank)
+		}
+		qs = append(qs, &dto.Quantile{
+			Quantile: proto.Float64(rank),
+			Value:    proto.Float64(q),
+		})
+	}
+
+	s.mtx.Unlock()
+
+	if len(qs) > 0 {
+		sort.Sort(quantSort(qs))
+	}
+	sum.Quantile = qs
+
+	out.Summary = sum
+	out.Label = s.labelPairs
+	return nil
+}
+
+func (s *summary) newStream() *quantile.Stream {
+	return quantile.NewTargeted(s.objectives)
+}
+
+// asyncFlush needs bufMtx locked.
+func (s *summary) asyncFlush(now time.Time) {
+	s.mtx.Lock()
+	s.swapBufs(now)
+
+	// Unblock the original goroutine that was responsible for the mutation
+	// that triggered the compaction.  But hold onto the global non-buffer
+	// state mutex until the operation finishes.
+	go func() {
+		s.flushColdBuf()
+		s.mtx.Unlock()
+	}()
+}
+
+// rotateStreams needs mtx AND bufMtx locked.
+func (s *summary) maybeRotateStreams() {
+	for !s.hotBufExpTime.Equal(s.headStreamExpTime) {
+		s.headStream.Reset()
+		s.headStreamIdx++
+		if s.headStreamIdx >= len(s.streams) {
+			s.headStreamIdx = 0
+		}
+		s.headStream = s.streams[s.headStreamIdx]
+		s.headStreamExpTime = s.headStreamExpTime.Add(s.streamDuration)
+	}
+}
+
+// flushColdBuf needs mtx locked.
+func (s *summary) flushColdBuf() {
+	for _, v := range s.coldBuf {
+		for _, stream := range s.streams {
+			stream.Insert(v)
+		}
+		s.cnt++
+		s.sum += v
+	}
+	s.coldBuf = s.coldBuf[0:0]
+	s.maybeRotateStreams()
+}
+
+// swapBufs needs mtx AND bufMtx locked, coldBuf must be empty.
+func (s *summary) swapBufs(now time.Time) {
+	if len(s.coldBuf) != 0 {
+		panic("coldBuf is not empty")
+	}
+	s.hotBuf, s.coldBuf = s.coldBuf, s.hotBuf
+	// hotBuf is now empty and gets new expiration set.
+	for now.After(s.hotBufExpTime) {
+		s.hotBufExpTime = s.hotBufExpTime.Add(s.streamDuration)
+	}
+}
+
+type quantSort []*dto.Quantile
+
+func (s quantSort) Len() int {
+	return len(s)
+}
+
+func (s quantSort) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+func (s quantSort) Less(i, j int) bool {
+	return s[i].GetQuantile() < s[j].GetQuantile()
+}
+
+// SummaryVec is a Collector that bundles a set of Summaries that all share the
+// same Desc, but have different values for their variable labels. This is used
+// if you want to count the same thing partitioned by various dimensions
+// (e.g. HTTP request latencies, partitioned by status code and method). Create
+// instances with NewSummaryVec.
+type SummaryVec struct {
+	*MetricVec
+}
+
+// NewSummaryVec creates a new SummaryVec based on the provided SummaryOpts and
+// partitioned by the given label names. At least one label name must be
+// provided.
+func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &SummaryVec{
+		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
+			return newSummary(desc, opts, lvs...)
+		}),
+	}
+}
+
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns a Summary and not a
+// Metric so that no type conversion is required.
+func (m *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Summary, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Summary), err
+	}
+	return nil, err
+}
+
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns a Summary and not a Metric so that no
+// type conversion is required.
+func (m *SummaryVec) GetMetricWith(labels Labels) (Summary, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
+	if metric != nil {
+		return metric.(Summary), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. By not returning an
+// error, WithLabelValues allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Observe(42.21)
+func (m *SummaryVec) WithLabelValues(lvs ...string) Summary {
+	return m.MetricVec.WithLabelValues(lvs...).(Summary)
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. By not returning an error, With allows shortcuts like
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Observe(42.21)
+func (m *SummaryVec) With(labels Labels) Summary {
+	return m.MetricVec.With(labels).(Summary)
+}
+
+type constSummary struct {
+	desc       *Desc
+	count      uint64
+	sum        float64
+	quantiles  map[float64]float64
+	labelPairs []*dto.LabelPair
+}
+
+func (s *constSummary) Desc() *Desc {
+	return s.desc
+}
+
+func (s *constSummary) Write(out *dto.Metric) error {
+	sum := &dto.Summary{}
+	qs := make([]*dto.Quantile, 0, len(s.quantiles))
+
+	sum.SampleCount = proto.Uint64(s.count)
+	sum.SampleSum = proto.Float64(s.sum)
+
+	for rank, q := range s.quantiles {
+		qs = append(qs, &dto.Quantile{
+			Quantile: proto.Float64(rank),
+			Value:    proto.Float64(q),
+		})
+	}
+
+	if len(qs) > 0 {
+		sort.Sort(quantSort(qs))
+	}
+	sum.Quantile = qs
+
+	out.Summary = sum
+	out.Label = s.labelPairs
+
+	return nil
+}
+
+// NewConstSummary returns a metric representing a Prometheus summary with fixed
+// values for the count, sum, and quantiles. As those parameters cannot be
+// changed, the returned value does not implement the Summary interface (but
+// only the Metric interface). Users of this package will not have much use for
+// it in regular operations. However, when implementing custom Collectors, it is
+// useful as a throw-away metric that is generated on the fly to send it to
+// Prometheus in the Collect method.
+//
+// quantiles maps ranks to quantile values. For example, a median latency of
+// 0.23s and a 99th percentile latency of 0.56s would be expressed as:
+//     map[float64]float64{0.5: 0.23, 0.99: 0.56}
+//
+// NewConstSummary returns an error if the length of labelValues is not
+// consistent with the variable labels in Desc.
+func NewConstSummary(
+	desc *Desc,
+	count uint64,
+	sum float64,
+	quantiles map[float64]float64,
+	labelValues ...string,
+) (Metric, error) {
+	if len(desc.variableLabels) != len(labelValues) {
+		return nil, errInconsistentCardinality
+	}
+	return &constSummary{
+		desc:       desc,
+		count:      count,
+		sum:        sum,
+		quantiles:  quantiles,
+		labelPairs: makeLabelPairs(desc, labelValues),
+	}, nil
+}
+
+// MustNewConstSummary is a version of NewConstSummary that panics where
+// NewConstMetric would have returned an error.
+func MustNewConstSummary(
+	desc *Desc,
+	count uint64,
+	sum float64,
+	quantiles map[float64]float64,
+	labelValues ...string,
+) Metric {
+	m, err := NewConstSummary(desc, count, sum, quantiles, labelValues...)
+	if err != nil {
+		panic(err)
+	}
+	return m
+}

vendor/github.com/prometheus/client_golang/prometheus/untyped.go

@@ -0,0 +1,138 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+// Untyped is a Metric that represents a single numerical value that can
+// arbitrarily go up and down.
+//
+// An Untyped metric works the same as a Gauge. The only difference is that to
+// no type information is implied.
+//
+// To create Untyped instances, use NewUntyped.
+type Untyped interface {
+	Metric
+	Collector
+
+	// Set sets the Untyped metric to an arbitrary value.
+	Set(float64)
+	// Inc increments the Untyped metric by 1.
+	Inc()
+	// Dec decrements the Untyped metric by 1.
+	Dec()
+	// Add adds the given value to the Untyped metric. (The value can be
+	// negative, resulting in a decrease.)
+	Add(float64)
+	// Sub subtracts the given value from the Untyped metric. (The value can
+	// be negative, resulting in an increase.)
+	Sub(float64)
+}
+
+// UntypedOpts is an alias for Opts. See there for doc comments.
+type UntypedOpts Opts
+
+// NewUntyped creates a new Untyped metric from the provided UntypedOpts.
+func NewUntyped(opts UntypedOpts) Untyped {
+	return newValue(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), UntypedValue, 0)
+}
+
+// UntypedVec is a Collector that bundles a set of Untyped metrics that all
+// share the same Desc, but have different values for their variable
+// labels. This is used if you want to count the same thing partitioned by
+// various dimensions. Create instances with NewUntypedVec.
+type UntypedVec struct {
+	*MetricVec
+}
+
+// NewUntypedVec creates a new UntypedVec based on the provided UntypedOpts and
+// partitioned by the given label names. At least one label name must be
+// provided.
+func NewUntypedVec(opts UntypedOpts, labelNames []string) *UntypedVec {
+	desc := NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		labelNames,
+		opts.ConstLabels,
+	)
+	return &UntypedVec{
+		MetricVec: newMetricVec(desc, func(lvs ...string) Metric {
+			return newValue(desc, UntypedValue, 0, lvs...)
+		}),
+	}
+}
+
+// GetMetricWithLabelValues replaces the method of the same name in
+// MetricVec. The difference is that this method returns an Untyped and not a
+// Metric so that no type conversion is required.
+func (m *UntypedVec) GetMetricWithLabelValues(lvs ...string) (Untyped, error) {
+	metric, err := m.MetricVec.GetMetricWithLabelValues(lvs...)
+	if metric != nil {
+		return metric.(Untyped), err
+	}
+	return nil, err
+}
+
+// GetMetricWith replaces the method of the same name in MetricVec. The
+// difference is that this method returns an Untyped and not a Metric so that no
+// type conversion is required.
+func (m *UntypedVec) GetMetricWith(labels Labels) (Untyped, error) {
+	metric, err := m.MetricVec.GetMetricWith(labels)
+	if metric != nil {
+		return metric.(Untyped), err
+	}
+	return nil, err
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics where
+// GetMetricWithLabelValues would have returned an error. By not returning an
+// error, WithLabelValues allows shortcuts like
+//     myVec.WithLabelValues("404", "GET").Add(42)
+func (m *UntypedVec) WithLabelValues(lvs ...string) Untyped {
+	return m.MetricVec.WithLabelValues(lvs...).(Untyped)
+}
+
+// With works as GetMetricWith, but panics where GetMetricWithLabels would have
+// returned an error. By not returning an error, With allows shortcuts like
+//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
+func (m *UntypedVec) With(labels Labels) Untyped {
+	return m.MetricVec.With(labels).(Untyped)
+}
+
+// UntypedFunc is an Untyped whose value is determined at collect time by
+// calling a provided function.
+//
+// To create UntypedFunc instances, use NewUntypedFunc.
+type UntypedFunc interface {
+	Metric
+	Collector
+}
+
+// NewUntypedFunc creates a new UntypedFunc based on the provided
+// UntypedOpts. The value reported is determined by calling the given function
+// from within the Write method. Take into account that metric collection may
+// happen concurrently. If that results in concurrent calls to Write, like in
+// the case where an UntypedFunc is directly registered with Prometheus, the
+// provided function must be concurrency-safe.
+func NewUntypedFunc(opts UntypedOpts, function func() float64) UntypedFunc {
+	return newValueFunc(NewDesc(
+		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
+		opts.Help,
+		nil,
+		opts.ConstLabels,
+	), UntypedValue, function)
+}

vendor/github.com/prometheus/client_golang/prometheus/value.go

@@ -0,0 +1,234 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"errors"
+	"fmt"
+	"math"
+	"sort"
+	"sync/atomic"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/golang/protobuf/proto"
+)
+
+// ValueType is an enumeration of metric types that represent a simple value.
+type ValueType int
+
+// Possible values for the ValueType enum.
+const (
+	_ ValueType = iota
+	CounterValue
+	GaugeValue
+	UntypedValue
+)
+
+var errInconsistentCardinality = errors.New("inconsistent label cardinality")
+
+// value is a generic metric for simple values. It implements Metric, Collector,
+// Counter, Gauge, and Untyped. Its effective type is determined by
+// ValueType. This is a low-level building block used by the library to back the
+// implementations of Counter, Gauge, and Untyped.
+type value struct {
+	// valBits containst the bits of the represented float64 value. It has
+	// to go first in the struct to guarantee alignment for atomic
+	// operations.  http://golang.org/pkg/sync/atomic/#pkg-note-BUG
+	valBits uint64
+
+	selfCollector
+
+	desc       *Desc
+	valType    ValueType
+	labelPairs []*dto.LabelPair
+}
+
+// newValue returns a newly allocated value with the given Desc, ValueType,
+// sample value and label values. It panics if the number of label
+// values is different from the number of variable labels in Desc.
+func newValue(desc *Desc, valueType ValueType, val float64, labelValues ...string) *value {
+	if len(labelValues) != len(desc.variableLabels) {
+		panic(errInconsistentCardinality)
+	}
+	result := &value{
+		desc:       desc,
+		valType:    valueType,
+		valBits:    math.Float64bits(val),
+		labelPairs: makeLabelPairs(desc, labelValues),
+	}
+	result.init(result)
+	return result
+}
+
+func (v *value) Desc() *Desc {
+	return v.desc
+}
+
+func (v *value) Set(val float64) {
+	atomic.StoreUint64(&v.valBits, math.Float64bits(val))
+}
+
+func (v *value) Inc() {
+	v.Add(1)
+}
+
+func (v *value) Dec() {
+	v.Add(-1)
+}
+
+func (v *value) Add(val float64) {
+	for {
+		oldBits := atomic.LoadUint64(&v.valBits)
+		newBits := math.Float64bits(math.Float64frombits(oldBits) + val)
+		if atomic.CompareAndSwapUint64(&v.valBits, oldBits, newBits) {
+			return
+		}
+	}
+}
+
+func (v *value) Sub(val float64) {
+	v.Add(val * -1)
+}
+
+func (v *value) Write(out *dto.Metric) error {
+	val := math.Float64frombits(atomic.LoadUint64(&v.valBits))
+	return populateMetric(v.valType, val, v.labelPairs, out)
+}
+
+// valueFunc is a generic metric for simple values retrieved on collect time
+// from a function. It implements Metric and Collector. Its effective type is
+// determined by ValueType. This is a low-level building block used by the
+// library to back the implementations of CounterFunc, GaugeFunc, and
+// UntypedFunc.
+type valueFunc struct {
+	selfCollector
+
+	desc       *Desc
+	valType    ValueType
+	function   func() float64
+	labelPairs []*dto.LabelPair
+}
+
+// newValueFunc returns a newly allocated valueFunc with the given Desc and
+// ValueType. The value reported is determined by calling the given function
+// from within the Write method. Take into account that metric collection may
+// happen concurrently. If that results in concurrent calls to Write, like in
+// the case where a valueFunc is directly registered with Prometheus, the
+// provided function must be concurrency-safe.
+func newValueFunc(desc *Desc, valueType ValueType, function func() float64) *valueFunc {
+	result := &valueFunc{
+		desc:       desc,
+		valType:    valueType,
+		function:   function,
+		labelPairs: makeLabelPairs(desc, nil),
+	}
+	result.init(result)
+	return result
+}
+
+func (v *valueFunc) Desc() *Desc {
+	return v.desc
+}
+
+func (v *valueFunc) Write(out *dto.Metric) error {
+	return populateMetric(v.valType, v.function(), v.labelPairs, out)
+}
+
+// NewConstMetric returns a metric with one fixed value that cannot be
+// changed. Users of this package will not have much use for it in regular
+// operations. However, when implementing custom Collectors, it is useful as a
+// throw-away metric that is generated on the fly to send it to Prometheus in
+// the Collect method. NewConstMetric returns an error if the length of
+// labelValues is not consistent with the variable labels in Desc.
+func NewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) (Metric, error) {
+	if len(desc.variableLabels) != len(labelValues) {
+		return nil, errInconsistentCardinality
+	}
+	return &constMetric{
+		desc:       desc,
+		valType:    valueType,
+		val:        value,
+		labelPairs: makeLabelPairs(desc, labelValues),
+	}, nil
+}
+
+// MustNewConstMetric is a version of NewConstMetric that panics where
+// NewConstMetric would have returned an error.
+func MustNewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) Metric {
+	m, err := NewConstMetric(desc, valueType, value, labelValues...)
+	if err != nil {
+		panic(err)
+	}
+	return m
+}
+
+type constMetric struct {
+	desc       *Desc
+	valType    ValueType
+	val        float64
+	labelPairs []*dto.LabelPair
+}
+
+func (m *constMetric) Desc() *Desc {
+	return m.desc
+}
+
+func (m *constMetric) Write(out *dto.Metric) error {
+	return populateMetric(m.valType, m.val, m.labelPairs, out)
+}
+
+func populateMetric(
+	t ValueType,
+	v float64,
+	labelPairs []*dto.LabelPair,
+	m *dto.Metric,
+) error {
+	m.Label = labelPairs
+	switch t {
+	case CounterValue:
+		m.Counter = &dto.Counter{Value: proto.Float64(v)}
+	case GaugeValue:
+		m.Gauge = &dto.Gauge{Value: proto.Float64(v)}
+	case UntypedValue:
+		m.Untyped = &dto.Untyped{Value: proto.Float64(v)}
+	default:
+		return fmt.Errorf("encountered unknown type %v", t)
+	}
+	return nil
+}
+
+func makeLabelPairs(desc *Desc, labelValues []string) []*dto.LabelPair {
+	totalLen := len(desc.variableLabels) + len(desc.constLabelPairs)
+	if totalLen == 0 {
+		// Super fast path.
+		return nil
+	}
+	if len(desc.variableLabels) == 0 {
+		// Moderately fast path.
+		return desc.constLabelPairs
+	}
+	labelPairs := make([]*dto.LabelPair, 0, totalLen)
+	for i, n := range desc.variableLabels {
+		labelPairs = append(labelPairs, &dto.LabelPair{
+			Name:  proto.String(n),
+			Value: proto.String(labelValues[i]),
+		})
+	}
+	for _, lp := range desc.constLabelPairs {
+		labelPairs = append(labelPairs, lp)
+	}
+	sort.Sort(LabelPairSorter(labelPairs))
+	return labelPairs
+}

vendor/github.com/prometheus/client_golang/prometheus/vec.go

@@ -0,0 +1,404 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package prometheus
+
+import (
+	"fmt"
+	"sync"
+
+	"github.com/prometheus/common/model"
+)
+
+// MetricVec is a Collector to bundle metrics of the same name that
+// differ in their label values. MetricVec is usually not used directly but as a
+// building block for implementations of vectors of a given metric
+// type. GaugeVec, CounterVec, SummaryVec, and UntypedVec are examples already
+// provided in this package.
+type MetricVec struct {
+	mtx      sync.RWMutex // Protects the children.
+	children map[uint64][]metricWithLabelValues
+	desc     *Desc
+
+	newMetric   func(labelValues ...string) Metric
+	hashAdd     func(h uint64, s string) uint64 // replace hash function for testing collision handling
+	hashAddByte func(h uint64, b byte) uint64
+}
+
+// newMetricVec returns an initialized MetricVec. The concrete value is
+// returned for embedding into another struct.
+func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *MetricVec {
+	return &MetricVec{
+		children:    map[uint64][]metricWithLabelValues{},
+		desc:        desc,
+		newMetric:   newMetric,
+		hashAdd:     hashAdd,
+		hashAddByte: hashAddByte,
+	}
+}
+
+// metricWithLabelValues provides the metric and its label values for
+// disambiguation on hash collision.
+type metricWithLabelValues struct {
+	values []string
+	metric Metric
+}
+
+// Describe implements Collector. The length of the returned slice
+// is always one.
+func (m *MetricVec) Describe(ch chan<- *Desc) {
+	ch <- m.desc
+}
+
+// Collect implements Collector.
+func (m *MetricVec) Collect(ch chan<- Metric) {
+	m.mtx.RLock()
+	defer m.mtx.RUnlock()
+
+	for _, metrics := range m.children {
+		for _, metric := range metrics {
+			ch <- metric.metric
+		}
+	}
+}
+
+// GetMetricWithLabelValues returns the Metric for the given slice of label
+// values (same order as the VariableLabels in Desc). If that combination of
+// label values is accessed for the first time, a new Metric is created.
+//
+// It is possible to call this method without using the returned Metric to only
+// create the new Metric but leave it at its start value (e.g. a Summary or
+// Histogram without any observations). See also the SummaryVec example.
+//
+// Keeping the Metric for later use is possible (and should be considered if
+// performance is critical), but keep in mind that Reset, DeleteLabelValues and
+// Delete can be used to delete the Metric from the MetricVec. In that case, the
+// Metric will still exist, but it will not be exported anymore, even if a
+// Metric with the same label values is created later. See also the CounterVec
+// example.
+//
+// An error is returned if the number of label values is not the same as the
+// number of VariableLabels in Desc.
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
+// an alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the GaugeVec example.
+func (m *MetricVec) GetMetricWithLabelValues(lvs ...string) (Metric, error) {
+	h, err := m.hashLabelValues(lvs)
+	if err != nil {
+		return nil, err
+	}
+
+	return m.getOrCreateMetricWithLabelValues(h, lvs), nil
+}
+
+// GetMetricWith returns the Metric for the given Labels map (the label names
+// must match those of the VariableLabels in Desc). If that label map is
+// accessed for the first time, a new Metric is created. Implications of
+// creating a Metric without using it and keeping the Metric for later use are
+// the same as for GetMetricWithLabelValues.
+//
+// An error is returned if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in Desc.
+//
+// This method is used for the same purpose as
+// GetMetricWithLabelValues(...string). See there for pros and cons of the two
+// methods.
+func (m *MetricVec) GetMetricWith(labels Labels) (Metric, error) {
+	h, err := m.hashLabels(labels)
+	if err != nil {
+		return nil, err
+	}
+
+	return m.getOrCreateMetricWithLabels(h, labels), nil
+}
+
+// WithLabelValues works as GetMetricWithLabelValues, but panics if an error
+// occurs. The method allows neat syntax like:
+//     httpReqs.WithLabelValues("404", "POST").Inc()
+func (m *MetricVec) WithLabelValues(lvs ...string) Metric {
+	metric, err := m.GetMetricWithLabelValues(lvs...)
+	if err != nil {
+		panic(err)
+	}
+	return metric
+}
+
+// With works as GetMetricWith, but panics if an error occurs. The method allows
+// neat syntax like:
+//     httpReqs.With(Labels{"status":"404", "method":"POST"}).Inc()
+func (m *MetricVec) With(labels Labels) Metric {
+	metric, err := m.GetMetricWith(labels)
+	if err != nil {
+		panic(err)
+	}
+	return metric
+}
+
+// DeleteLabelValues removes the metric where the variable labels are the same
+// as those passed in as labels (same order as the VariableLabels in Desc). It
+// returns true if a metric was deleted.
+//
+// It is not an error if the number of label values is not the same as the
+// number of VariableLabels in Desc.  However, such inconsistent label count can
+// never match an actual Metric, so the method will always return false in that
+// case.
+//
+// Note that for more than one label value, this method is prone to mistakes
+// caused by an incorrect order of arguments. Consider Delete(Labels) as an
+// alternative to avoid that type of mistake. For higher label numbers, the
+// latter has a much more readable (albeit more verbose) syntax, but it comes
+// with a performance overhead (for creating and processing the Labels map).
+// See also the CounterVec example.
+func (m *MetricVec) DeleteLabelValues(lvs ...string) bool {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
+	h, err := m.hashLabelValues(lvs)
+	if err != nil {
+		return false
+	}
+	return m.deleteByHashWithLabelValues(h, lvs)
+}
+
+// Delete deletes the metric where the variable labels are the same as those
+// passed in as labels. It returns true if a metric was deleted.
+//
+// It is not an error if the number and names of the Labels are inconsistent
+// with those of the VariableLabels in the Desc of the MetricVec. However, such
+// inconsistent Labels can never match an actual Metric, so the method will
+// always return false in that case.
+//
+// This method is used for the same purpose as DeleteLabelValues(...string). See
+// there for pros and cons of the two methods.
+func (m *MetricVec) Delete(labels Labels) bool {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
+	h, err := m.hashLabels(labels)
+	if err != nil {
+		return false
+	}
+
+	return m.deleteByHashWithLabels(h, labels)
+}
+
+// deleteByHashWithLabelValues removes the metric from the hash bucket h. If
+// there are multiple matches in the bucket, use lvs to select a metric and
+// remove only that metric.
+func (m *MetricVec) deleteByHashWithLabelValues(h uint64, lvs []string) bool {
+	metrics, ok := m.children[h]
+	if !ok {
+		return false
+	}
+
+	i := m.findMetricWithLabelValues(metrics, lvs)
+	if i >= len(metrics) {
+		return false
+	}
+
+	if len(metrics) > 1 {
+		m.children[h] = append(metrics[:i], metrics[i+1:]...)
+	} else {
+		delete(m.children, h)
+	}
+	return true
+}
+
+// deleteByHashWithLabels removes the metric from the hash bucket h. If there
+// are multiple matches in the bucket, use lvs to select a metric and remove
+// only that metric.
+func (m *MetricVec) deleteByHashWithLabels(h uint64, labels Labels) bool {
+	metrics, ok := m.children[h]
+	if !ok {
+		return false
+	}
+	i := m.findMetricWithLabels(metrics, labels)
+	if i >= len(metrics) {
+		return false
+	}
+
+	if len(metrics) > 1 {
+		m.children[h] = append(metrics[:i], metrics[i+1:]...)
+	} else {
+		delete(m.children, h)
+	}
+	return true
+}
+
+// Reset deletes all metrics in this vector.
+func (m *MetricVec) Reset() {
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+
+	for h := range m.children {
+		delete(m.children, h)
+	}
+}
+
+func (m *MetricVec) hashLabelValues(vals []string) (uint64, error) {
+	if len(vals) != len(m.desc.variableLabels) {
+		return 0, errInconsistentCardinality
+	}
+	h := hashNew()
+	for _, val := range vals {
+		h = m.hashAdd(h, val)
+		h = m.hashAddByte(h, model.SeparatorByte)
+	}
+	return h, nil
+}
+
+func (m *MetricVec) hashLabels(labels Labels) (uint64, error) {
+	if len(labels) != len(m.desc.variableLabels) {
+		return 0, errInconsistentCardinality
+	}
+	h := hashNew()
+	for _, label := range m.desc.variableLabels {
+		val, ok := labels[label]
+		if !ok {
+			return 0, fmt.Errorf("label name %q missing in label map", label)
+		}
+		h = m.hashAdd(h, val)
+		h = m.hashAddByte(h, model.SeparatorByte)
+	}
+	return h, nil
+}
+
+// getOrCreateMetricWithLabelValues retrieves the metric by hash and label value
+// or creates it and returns the new one.
+//
+// This function holds the mutex.
+func (m *MetricVec) getOrCreateMetricWithLabelValues(hash uint64, lvs []string) Metric {
+	m.mtx.RLock()
+	metric, ok := m.getMetricWithLabelValues(hash, lvs)
+	m.mtx.RUnlock()
+	if ok {
+		return metric
+	}
+
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+	metric, ok = m.getMetricWithLabelValues(hash, lvs)
+	if !ok {
+		// Copy to avoid allocation in case wo don't go down this code path.
+		copiedLVs := make([]string, len(lvs))
+		copy(copiedLVs, lvs)
+		metric = m.newMetric(copiedLVs...)
+		m.children[hash] = append(m.children[hash], metricWithLabelValues{values: copiedLVs, metric: metric})
+	}
+	return metric
+}
+
+// getOrCreateMetricWithLabelValues retrieves the metric by hash and label value
+// or creates it and returns the new one.
+//
+// This function holds the mutex.
+func (m *MetricVec) getOrCreateMetricWithLabels(hash uint64, labels Labels) Metric {
+	m.mtx.RLock()
+	metric, ok := m.getMetricWithLabels(hash, labels)
+	m.mtx.RUnlock()
+	if ok {
+		return metric
+	}
+
+	m.mtx.Lock()
+	defer m.mtx.Unlock()
+	metric, ok = m.getMetricWithLabels(hash, labels)
+	if !ok {
+		lvs := m.extractLabelValues(labels)
+		metric = m.newMetric(lvs...)
+		m.children[hash] = append(m.children[hash], metricWithLabelValues{values: lvs, metric: metric})
+	}
+	return metric
+}
+
+// getMetricWithLabelValues gets a metric while handling possible collisions in
+// the hash space. Must be called while holding read mutex.
+func (m *MetricVec) getMetricWithLabelValues(h uint64, lvs []string) (Metric, bool) {
+	metrics, ok := m.children[h]
+	if ok {
+		if i := m.findMetricWithLabelValues(metrics, lvs); i < len(metrics) {
+			return metrics[i].metric, true
+		}
+	}
+	return nil, false
+}
+
+// getMetricWithLabels gets a metric while handling possible collisions in
+// the hash space. Must be called while holding read mutex.
+func (m *MetricVec) getMetricWithLabels(h uint64, labels Labels) (Metric, bool) {
+	metrics, ok := m.children[h]
+	if ok {
+		if i := m.findMetricWithLabels(metrics, labels); i < len(metrics) {
+			return metrics[i].metric, true
+		}
+	}
+	return nil, false
+}
+
+// findMetricWithLabelValues returns the index of the matching metric or
+// len(metrics) if not found.
+func (m *MetricVec) findMetricWithLabelValues(metrics []metricWithLabelValues, lvs []string) int {
+	for i, metric := range metrics {
+		if m.matchLabelValues(metric.values, lvs) {
+			return i
+		}
+	}
+	return len(metrics)
+}
+
+// findMetricWithLabels returns the index of the matching metric or len(metrics)
+// if not found.
+func (m *MetricVec) findMetricWithLabels(metrics []metricWithLabelValues, labels Labels) int {
+	for i, metric := range metrics {
+		if m.matchLabels(metric.values, labels) {
+			return i
+		}
+	}
+	return len(metrics)
+}
+
+func (m *MetricVec) matchLabelValues(values []string, lvs []string) bool {
+	if len(values) != len(lvs) {
+		return false
+	}
+	for i, v := range values {
+		if v != lvs[i] {
+			return false
+		}
+	}
+	return true
+}
+
+func (m *MetricVec) matchLabels(values []string, labels Labels) bool {
+	if len(labels) != len(values) {
+		return false
+	}
+	for i, k := range m.desc.variableLabels {
+		if values[i] != labels[k] {
+			return false
+		}
+	}
+	return true
+}
+
+func (m *MetricVec) extractLabelValues(labels Labels) []string {
+	labelValues := make([]string, len(labels))
+	for i, k := range m.desc.variableLabels {
+		labelValues[i] = labels[k]
+	}
+	return labelValues
+}

vendor/github.com/prometheus/client_model/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
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+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/prometheus/client_model/NOTICE

@@ -0,0 +1,5 @@
+Data model artifacts for Prometheus.
+Copyright 2012-2015 The Prometheus Authors
+
+This product includes software developed at
+SoundCloud Ltd. (http://soundcloud.com/).

vendor/github.com/prometheus/client_model/go/metrics.pb.go

@@ -0,0 +1,364 @@
+// Code generated by protoc-gen-go.
+// source: metrics.proto
+// DO NOT EDIT!
+
+/*
+Package io_prometheus_client is a generated protocol buffer package.
+
+It is generated from these files:
+	metrics.proto
+
+It has these top-level messages:
+	LabelPair
+	Gauge
+	Counter
+	Quantile
+	Summary
+	Untyped
+	Histogram
+	Bucket
+	Metric
+	MetricFamily
+*/
+package io_prometheus_client
+
+import proto "github.com/golang/protobuf/proto"
+import math "math"
+
+// Reference imports to suppress errors if they are not otherwise used.
+var _ = proto.Marshal
+var _ = math.Inf
+
+type MetricType int32
+
+const (
+	MetricType_COUNTER   MetricType = 0
+	MetricType_GAUGE     MetricType = 1
+	MetricType_SUMMARY   MetricType = 2
+	MetricType_UNTYPED   MetricType = 3
+	MetricType_HISTOGRAM MetricType = 4
+)
+
+var MetricType_name = map[int32]string{
+	0: "COUNTER",
+	1: "GAUGE",
+	2: "SUMMARY",
+	3: "UNTYPED",
+	4: "HISTOGRAM",
+}
+var MetricType_value = map[string]int32{
+	"COUNTER":   0,
+	"GAUGE":     1,
+	"SUMMARY":   2,
+	"UNTYPED":   3,
+	"HISTOGRAM": 4,
+}
+
+func (x MetricType) Enum() *MetricType {
+	p := new(MetricType)
+	*p = x
+	return p
+}
+func (x MetricType) String() string {
+	return proto.EnumName(MetricType_name, int32(x))
+}
+func (x *MetricType) UnmarshalJSON(data []byte) error {
+	value, err := proto.UnmarshalJSONEnum(MetricType_value, data, "MetricType")
+	if err != nil {
+		return err
+	}
+	*x = MetricType(value)
+	return nil
+}
+
+type LabelPair struct {
+	Name             *string `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
+	Value            *string `protobuf:"bytes,2,opt,name=value" json:"value,omitempty"`
+	XXX_unrecognized []byte  `json:"-"`
+}
+
+func (m *LabelPair) Reset()         { *m = LabelPair{} }
+func (m *LabelPair) String() string { return proto.CompactTextString(m) }
+func (*LabelPair) ProtoMessage()    {}
+
+func (m *LabelPair) GetName() string {
+	if m != nil && m.Name != nil {
+		return *m.Name
+	}
+	return ""
+}
+
+func (m *LabelPair) GetValue() string {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return ""
+}
+
+type Gauge struct {
+	Value            *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	XXX_unrecognized []byte   `json:"-"`
+}
+
+func (m *Gauge) Reset()         { *m = Gauge{} }
+func (m *Gauge) String() string { return proto.CompactTextString(m) }
+func (*Gauge) ProtoMessage()    {}
+
+func (m *Gauge) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+type Counter struct {
+	Value            *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	XXX_unrecognized []byte   `json:"-"`
+}
+
+func (m *Counter) Reset()         { *m = Counter{} }
+func (m *Counter) String() string { return proto.CompactTextString(m) }
+func (*Counter) ProtoMessage()    {}
+
+func (m *Counter) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+type Quantile struct {
+	Quantile         *float64 `protobuf:"fixed64,1,opt,name=quantile" json:"quantile,omitempty"`
+	Value            *float64 `protobuf:"fixed64,2,opt,name=value" json:"value,omitempty"`
+	XXX_unrecognized []byte   `json:"-"`
+}
+
+func (m *Quantile) Reset()         { *m = Quantile{} }
+func (m *Quantile) String() string { return proto.CompactTextString(m) }
+func (*Quantile) ProtoMessage()    {}
+
+func (m *Quantile) GetQuantile() float64 {
+	if m != nil && m.Quantile != nil {
+		return *m.Quantile
+	}
+	return 0
+}
+
+func (m *Quantile) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+type Summary struct {
+	SampleCount      *uint64     `protobuf:"varint,1,opt,name=sample_count" json:"sample_count,omitempty"`
+	SampleSum        *float64    `protobuf:"fixed64,2,opt,name=sample_sum" json:"sample_sum,omitempty"`
+	Quantile         []*Quantile `protobuf:"bytes,3,rep,name=quantile" json:"quantile,omitempty"`
+	XXX_unrecognized []byte      `json:"-"`
+}
+
+func (m *Summary) Reset()         { *m = Summary{} }
+func (m *Summary) String() string { return proto.CompactTextString(m) }
+func (*Summary) ProtoMessage()    {}
+
+func (m *Summary) GetSampleCount() uint64 {
+	if m != nil && m.SampleCount != nil {
+		return *m.SampleCount
+	}
+	return 0
+}
+
+func (m *Summary) GetSampleSum() float64 {
+	if m != nil && m.SampleSum != nil {
+		return *m.SampleSum
+	}
+	return 0
+}
+
+func (m *Summary) GetQuantile() []*Quantile {
+	if m != nil {
+		return m.Quantile
+	}
+	return nil
+}
+
+type Untyped struct {
+	Value            *float64 `protobuf:"fixed64,1,opt,name=value" json:"value,omitempty"`
+	XXX_unrecognized []byte   `json:"-"`
+}
+
+func (m *Untyped) Reset()         { *m = Untyped{} }
+func (m *Untyped) String() string { return proto.CompactTextString(m) }
+func (*Untyped) ProtoMessage()    {}
+
+func (m *Untyped) GetValue() float64 {
+	if m != nil && m.Value != nil {
+		return *m.Value
+	}
+	return 0
+}
+
+type Histogram struct {
+	SampleCount      *uint64   `protobuf:"varint,1,opt,name=sample_count" json:"sample_count,omitempty"`
+	SampleSum        *float64  `protobuf:"fixed64,2,opt,name=sample_sum" json:"sample_sum,omitempty"`
+	Bucket           []*Bucket `protobuf:"bytes,3,rep,name=bucket" json:"bucket,omitempty"`
+	XXX_unrecognized []byte    `json:"-"`
+}
+
+func (m *Histogram) Reset()         { *m = Histogram{} }
+func (m *Histogram) String() string { return proto.CompactTextString(m) }
+func (*Histogram) ProtoMessage()    {}
+
+func (m *Histogram) GetSampleCount() uint64 {
+	if m != nil && m.SampleCount != nil {
+		return *m.SampleCount
+	}
+	return 0
+}
+
+func (m *Histogram) GetSampleSum() float64 {
+	if m != nil && m.SampleSum != nil {
+		return *m.SampleSum
+	}
+	return 0
+}
+
+func (m *Histogram) GetBucket() []*Bucket {
+	if m != nil {
+		return m.Bucket
+	}
+	return nil
+}
+
+type Bucket struct {
+	CumulativeCount  *uint64  `protobuf:"varint,1,opt,name=cumulative_count" json:"cumulative_count,omitempty"`
+	UpperBound       *float64 `protobuf:"fixed64,2,opt,name=upper_bound" json:"upper_bound,omitempty"`
+	XXX_unrecognized []byte   `json:"-"`
+}
+
+func (m *Bucket) Reset()         { *m = Bucket{} }
+func (m *Bucket) String() string { return proto.CompactTextString(m) }
+func (*Bucket) ProtoMessage()    {}
+
+func (m *Bucket) GetCumulativeCount() uint64 {
+	if m != nil && m.CumulativeCount != nil {
+		return *m.CumulativeCount
+	}
+	return 0
+}
+
+func (m *Bucket) GetUpperBound() float64 {
+	if m != nil && m.UpperBound != nil {
+		return *m.UpperBound
+	}
+	return 0
+}
+
+type Metric struct {
+	Label            []*LabelPair `protobuf:"bytes,1,rep,name=label" json:"label,omitempty"`
+	Gauge            *Gauge       `protobuf:"bytes,2,opt,name=gauge" json:"gauge,omitempty"`
+	Counter          *Counter     `protobuf:"bytes,3,opt,name=counter" json:"counter,omitempty"`
+	Summary          *Summary     `protobuf:"bytes,4,opt,name=summary" json:"summary,omitempty"`
+	Untyped          *Untyped     `protobuf:"bytes,5,opt,name=untyped" json:"untyped,omitempty"`
+	Histogram        *Histogram   `protobuf:"bytes,7,opt,name=histogram" json:"histogram,omitempty"`
+	TimestampMs      *int64       `protobuf:"varint,6,opt,name=timestamp_ms" json:"timestamp_ms,omitempty"`
+	XXX_unrecognized []byte       `json:"-"`
+}
+
+func (m *Metric) Reset()         { *m = Metric{} }
+func (m *Metric) String() string { return proto.CompactTextString(m) }
+func (*Metric) ProtoMessage()    {}
+
+func (m *Metric) GetLabel() []*LabelPair {
+	if m != nil {
+		return m.Label
+	}
+	return nil
+}
+
+func (m *Metric) GetGauge() *Gauge {
+	if m != nil {
+		return m.Gauge
+	}
+	return nil
+}
+
+func (m *Metric) GetCounter() *Counter {
+	if m != nil {
+		return m.Counter
+	}
+	return nil
+}
+
+func (m *Metric) GetSummary() *Summary {
+	if m != nil {
+		return m.Summary
+	}
+	return nil
+}
+
+func (m *Metric) GetUntyped() *Untyped {
+	if m != nil {
+		return m.Untyped
+	}
+	return nil
+}
+
+func (m *Metric) GetHistogram() *Histogram {
+	if m != nil {
+		return m.Histogram
+	}
+	return nil
+}
+
+func (m *Metric) GetTimestampMs() int64 {
+	if m != nil && m.TimestampMs != nil {
+		return *m.TimestampMs
+	}
+	return 0
+}
+
+type MetricFamily struct {
+	Name             *string     `protobuf:"bytes,1,opt,name=name" json:"name,omitempty"`
+	Help             *string     `protobuf:"bytes,2,opt,name=help" json:"help,omitempty"`
+	Type             *MetricType `protobuf:"varint,3,opt,name=type,enum=io.prometheus.client.MetricType" json:"type,omitempty"`
+	Metric           []*Metric   `protobuf:"bytes,4,rep,name=metric" json:"metric,omitempty"`
+	XXX_unrecognized []byte      `json:"-"`
+}
+
+func (m *MetricFamily) Reset()         { *m = MetricFamily{} }
+func (m *MetricFamily) String() string { return proto.CompactTextString(m) }
+func (*MetricFamily) ProtoMessage()    {}
+
+func (m *MetricFamily) GetName() string {
+	if m != nil && m.Name != nil {
+		return *m.Name
+	}
+	return ""
+}
+
+func (m *MetricFamily) GetHelp() string {
+	if m != nil && m.Help != nil {
+		return *m.Help
+	}
+	return ""
+}
+
+func (m *MetricFamily) GetType() MetricType {
+	if m != nil && m.Type != nil {
+		return *m.Type
+	}
+	return MetricType_COUNTER
+}
+
+func (m *MetricFamily) GetMetric() []*Metric {
+	if m != nil {
+		return m.Metric
+	}
+	return nil
+}
+
+func init() {
+	proto.RegisterEnum("io.prometheus.client.MetricType", MetricType_name, MetricType_value)
+}

vendor/github.com/prometheus/client_model/ruby/LICENSE

@@ -0,0 +1,201 @@
+                              Apache License
+                        Version 2.0, January 2004
+                     http://www.apache.org/licenses/
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+1. Definitions.
+
+   "License" shall mean the terms and conditions for use, reproduction,
+   and distribution as defined by Sections 1 through 9 of this document.
+
+   "Licensor" shall mean the copyright owner or entity authorized by
+   the copyright owner that is granting the License.
+
+   "Legal Entity" shall mean the union of the acting entity and all
+   other entities that control, are controlled by, or are under common
+   control with that entity. For the purposes of this definition,
+   "control" means (i) the power, direct or indirect, to cause the
+   direction or management of such entity, whether by contract or
+   otherwise, or (ii) ownership of fifty percent (50%) or more of the
+   outstanding shares, or (iii) beneficial ownership of such entity.
+
+   "You" (or "Your") shall mean an individual or Legal Entity
+   exercising permissions granted by this License.
+
+   "Source" form shall mean the preferred form for making modifications,
+   including but not limited to software source code, documentation
+   source, and configuration files.
+
+   "Object" form shall mean any form resulting from mechanical
+   transformation or translation of a Source form, including but
+   not limited to compiled object code, generated documentation,
+   and conversions to other media types.
+
+   "Work" shall mean the work of authorship, whether in Source or
+   Object form, made available under the License, as indicated by a
+   copyright notice that is included in or attached to the work
+   (an example is provided in the Appendix below).
+
+   "Derivative Works" shall mean any work, whether in Source or Object
+   form, that is based on (or derived from) the Work and for which the
+   editorial revisions, annotations, elaborations, or other modifications
+   represent, as a whole, an original work of authorship. For the purposes
+   of this License, Derivative Works shall not include works that remain
+   separable from, or merely link (or bind by name) to the interfaces of,
+   the Work and Derivative Works thereof.
+
+   "Contribution" shall mean any work of authorship, including
+   the original version of the Work and any modifications or additions
+   to that Work or Derivative Works thereof, that is intentionally
+   submitted to Licensor for inclusion in the Work by the copyright owner
+   or by an individual or Legal Entity authorized to submit on behalf of
+   the copyright owner. For the purposes of this definition, "submitted"
+   means any form of electronic, verbal, or written communication sent
+   to the Licensor or its representatives, including but not limited to
+   communication on electronic mailing lists, source code control systems,
+   and issue tracking systems that are managed by, or on behalf of, the
+   Licensor for the purpose of discussing and improving the Work, but
+   excluding communication that is conspicuously marked or otherwise
+   designated in writing by the copyright owner as "Not a Contribution."
+
+   "Contributor" shall mean Licensor and any individual or Legal Entity
+   on behalf of whom a Contribution has been received by Licensor and
+   subsequently incorporated within the Work.
+
+2. Grant of Copyright License. Subject to the terms and conditions of
+   this License, each Contributor hereby grants to You a perpetual,
+   worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+   copyright license to reproduce, prepare Derivative Works of,
+   publicly display, publicly perform, sublicense, and distribute the
+   Work and such Derivative Works in Source or Object form.
+
+3. Grant of Patent License. Subject to the terms and conditions of
+   this License, each Contributor hereby grants to You a perpetual,
+   worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+   (except as stated in this section) patent license to make, have made,
+   use, offer to sell, sell, import, and otherwise transfer the Work,
+   where such license applies only to those patent claims licensable
+   by such Contributor that are necessarily infringed by their
+   Contribution(s) alone or by combination of their Contribution(s)
+   with the Work to which such Contribution(s) was submitted. If You
+   institute patent litigation against any entity (including a
+   cross-claim or counterclaim in a lawsuit) alleging that the Work
+   or a Contribution incorporated within the Work constitutes direct
+   or contributory patent infringement, then any patent licenses
+   granted to You under this License for that Work shall terminate
+   as of the date such litigation is filed.
+
+4. Redistribution. You may reproduce and distribute copies of the
+   Work or Derivative Works thereof in any medium, with or without
+   modifications, and in Source or Object form, provided that You
+   meet the following conditions:
+
+   (a) You must give any other recipients of the Work or
+       Derivative Works a copy of this License; and
+
+   (b) You must cause any modified files to carry prominent notices
+       stating that You changed the files; and
+
+   (c) You must retain, in the Source form of any Derivative Works
+       that You distribute, all copyright, patent, trademark, and
+       attribution notices from the Source form of the Work,
+       excluding those notices that do not pertain to any part of
+       the Derivative Works; and
+
+   (d) If the Work includes a "NOTICE" text file as part of its
+       distribution, then any Derivative Works that You distribute must
+       include a readable copy of the attribution notices contained
+       within such NOTICE file, excluding those notices that do not
+       pertain to any part of the Derivative Works, in at least one
+       of the following places: within a NOTICE text file distributed
+       as part of the Derivative Works; within the Source form or
+       documentation, if provided along with the Derivative Works; or,
+       within a display generated by the Derivative Works, if and
+       wherever such third-party notices normally appear. The contents
+       of the NOTICE file are for informational purposes only and
+       do not modify the License. You may add Your own attribution
+       notices within Derivative Works that You distribute, alongside
+       or as an addendum to the NOTICE text from the Work, provided
+       that such additional attribution notices cannot be construed
+       as modifying the License.
+
+   You may add Your own copyright statement to Your modifications and
+   may provide additional or different license terms and conditions
+   for use, reproduction, or distribution of Your modifications, or
+   for any such Derivative Works as a whole, provided Your use,
+   reproduction, and distribution of the Work otherwise complies with
+   the conditions stated in this License.
+
+5. Submission of Contributions. Unless You explicitly state otherwise,
+   any Contribution intentionally submitted for inclusion in the Work
+   by You to the Licensor shall be under the terms and conditions of
+   this License, without any additional terms or conditions.
+   Notwithstanding the above, nothing herein shall supersede or modify
+   the terms of any separate license agreement you may have executed
+   with Licensor regarding such Contributions.
+
+6. Trademarks. This License does not grant permission to use the trade
+   names, trademarks, service marks, or product names of the Licensor,
+   except as required for reasonable and customary use in describing the
+   origin of the Work and reproducing the content of the NOTICE file.
+
+7. Disclaimer of Warranty. Unless required by applicable law or
+   agreed to in writing, Licensor provides the Work (and each
+   Contributor provides its Contributions) on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+   implied, including, without limitation, any warranties or conditions
+   of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+   PARTICULAR PURPOSE. You are solely responsible for determining the
+   appropriateness of using or redistributing the Work and assume any
+   risks associated with Your exercise of permissions under this License.
+
+8. Limitation of Liability. In no event and under no legal theory,
+   whether in tort (including negligence), contract, or otherwise,
+   unless required by applicable law (such as deliberate and grossly
+   negligent acts) or agreed to in writing, shall any Contributor be
+   liable to You for damages, including any direct, indirect, special,
+   incidental, or consequential damages of any character arising as a
+   result of this License or out of the use or inability to use the
+   Work (including but not limited to damages for loss of goodwill,
+   work stoppage, computer failure or malfunction, or any and all
+   other commercial damages or losses), even if such Contributor
+   has been advised of the possibility of such damages.
+
+9. Accepting Warranty or Additional Liability. While redistributing
+   the Work or Derivative Works thereof, You may choose to offer,
+   and charge a fee for, acceptance of support, warranty, indemnity,
+   or other liability obligations and/or rights consistent with this
+   License. However, in accepting such obligations, You may act only
+   on Your own behalf and on Your sole responsibility, not on behalf
+   of any other Contributor, and only if You agree to indemnify,
+   defend, and hold each Contributor harmless for any liability
+   incurred by, or claims asserted against, such Contributor by reason
+   of your accepting any such warranty or additional liability.
+
+END OF TERMS AND CONDITIONS
+
+APPENDIX: How to apply the Apache License to your work.
+
+   To apply the Apache License to your work, attach the following
+   boilerplate notice, with the fields enclosed by brackets "[]"
+   replaced with your own identifying information. (Don't include
+   the brackets!)  The text should be enclosed in the appropriate
+   comment syntax for the file format. We also recommend that a
+   file or class name and description of purpose be included on the
+   same "printed page" as the copyright notice for easier
+   identification within third-party archives.
+
+Copyright [yyyy] [name of copyright owner]
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

vendor/github.com/prometheus/common/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/prometheus/common/NOTICE

@@ -0,0 +1,5 @@
+Common libraries shared by Prometheus Go components.
+Copyright 2015 The Prometheus Authors
+
+This product includes software developed at
+SoundCloud Ltd. (http://soundcloud.com/).

vendor/github.com/prometheus/common/expfmt/decode.go

@@ -0,0 +1,429 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"fmt"
+	"io"
+	"math"
+	"mime"
+	"net/http"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/matttproud/golang_protobuf_extensions/pbutil"
+	"github.com/prometheus/common/model"
+)
+
+// Decoder types decode an input stream into metric families.
+type Decoder interface {
+	Decode(*dto.MetricFamily) error
+}
+
+// DecodeOptions contains options used by the Decoder and in sample extraction.
+type DecodeOptions struct {
+	// Timestamp is added to each value from the stream that has no explicit timestamp set.
+	Timestamp model.Time
+}
+
+// ResponseFormat extracts the correct format from a HTTP response header.
+// If no matching format can be found FormatUnknown is returned.
+func ResponseFormat(h http.Header) Format {
+	ct := h.Get(hdrContentType)
+
+	mediatype, params, err := mime.ParseMediaType(ct)
+	if err != nil {
+		return FmtUnknown
+	}
+
+	const textType = "text/plain"
+
+	switch mediatype {
+	case ProtoType:
+		if p, ok := params["proto"]; ok && p != ProtoProtocol {
+			return FmtUnknown
+		}
+		if e, ok := params["encoding"]; ok && e != "delimited" {
+			return FmtUnknown
+		}
+		return FmtProtoDelim
+
+	case textType:
+		if v, ok := params["version"]; ok && v != TextVersion {
+			return FmtUnknown
+		}
+		return FmtText
+	}
+
+	return FmtUnknown
+}
+
+// NewDecoder returns a new decoder based on the given input format.
+// If the input format does not imply otherwise, a text format decoder is returned.
+func NewDecoder(r io.Reader, format Format) Decoder {
+	switch format {
+	case FmtProtoDelim:
+		return &protoDecoder{r: r}
+	}
+	return &textDecoder{r: r}
+}
+
+// protoDecoder implements the Decoder interface for protocol buffers.
+type protoDecoder struct {
+	r io.Reader
+}
+
+// Decode implements the Decoder interface.
+func (d *protoDecoder) Decode(v *dto.MetricFamily) error {
+	_, err := pbutil.ReadDelimited(d.r, v)
+	if err != nil {
+		return err
+	}
+	if !model.IsValidMetricName(model.LabelValue(v.GetName())) {
+		return fmt.Errorf("invalid metric name %q", v.GetName())
+	}
+	for _, m := range v.GetMetric() {
+		if m == nil {
+			continue
+		}
+		for _, l := range m.GetLabel() {
+			if l == nil {
+				continue
+			}
+			if !model.LabelValue(l.GetValue()).IsValid() {
+				return fmt.Errorf("invalid label value %q", l.GetValue())
+			}
+			if !model.LabelName(l.GetName()).IsValid() {
+				return fmt.Errorf("invalid label name %q", l.GetName())
+			}
+		}
+	}
+	return nil
+}
+
+// textDecoder implements the Decoder interface for the text protocol.
+type textDecoder struct {
+	r    io.Reader
+	p    TextParser
+	fams []*dto.MetricFamily
+}
+
+// Decode implements the Decoder interface.
+func (d *textDecoder) Decode(v *dto.MetricFamily) error {
+	// TODO(fabxc): Wrap this as a line reader to make streaming safer.
+	if len(d.fams) == 0 {
+		// No cached metric families, read everything and parse metrics.
+		fams, err := d.p.TextToMetricFamilies(d.r)
+		if err != nil {
+			return err
+		}
+		if len(fams) == 0 {
+			return io.EOF
+		}
+		d.fams = make([]*dto.MetricFamily, 0, len(fams))
+		for _, f := range fams {
+			d.fams = append(d.fams, f)
+		}
+	}
+
+	*v = *d.fams[0]
+	d.fams = d.fams[1:]
+
+	return nil
+}
+
+// SampleDecoder wraps a Decoder to extract samples from the metric families
+// decoded by the wrapped Decoder.
+type SampleDecoder struct {
+	Dec  Decoder
+	Opts *DecodeOptions
+
+	f dto.MetricFamily
+}
+
+// Decode calls the Decode method of the wrapped Decoder and then extracts the
+// samples from the decoded MetricFamily into the provided model.Vector.
+func (sd *SampleDecoder) Decode(s *model.Vector) error {
+	err := sd.Dec.Decode(&sd.f)
+	if err != nil {
+		return err
+	}
+	*s, err = extractSamples(&sd.f, sd.Opts)
+	return err
+}
+
+// ExtractSamples builds a slice of samples from the provided metric
+// families. If an error occurrs during sample extraction, it continues to
+// extract from the remaining metric families. The returned error is the last
+// error that has occurred.
+func ExtractSamples(o *DecodeOptions, fams ...*dto.MetricFamily) (model.Vector, error) {
+	var (
+		all     model.Vector
+		lastErr error
+	)
+	for _, f := range fams {
+		some, err := extractSamples(f, o)
+		if err != nil {
+			lastErr = err
+			continue
+		}
+		all = append(all, some...)
+	}
+	return all, lastErr
+}
+
+func extractSamples(f *dto.MetricFamily, o *DecodeOptions) (model.Vector, error) {
+	switch f.GetType() {
+	case dto.MetricType_COUNTER:
+		return extractCounter(o, f), nil
+	case dto.MetricType_GAUGE:
+		return extractGauge(o, f), nil
+	case dto.MetricType_SUMMARY:
+		return extractSummary(o, f), nil
+	case dto.MetricType_UNTYPED:
+		return extractUntyped(o, f), nil
+	case dto.MetricType_HISTOGRAM:
+		return extractHistogram(o, f), nil
+	}
+	return nil, fmt.Errorf("expfmt.extractSamples: unknown metric family type %v", f.GetType())
+}
+
+func extractCounter(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Counter == nil {
+			continue
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName())
+
+		smpl := &model.Sample{
+			Metric: model.Metric(lset),
+			Value:  model.SampleValue(m.Counter.GetValue()),
+		}
+
+		if m.TimestampMs != nil {
+			smpl.Timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		} else {
+			smpl.Timestamp = o.Timestamp
+		}
+
+		samples = append(samples, smpl)
+	}
+
+	return samples
+}
+
+func extractGauge(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Gauge == nil {
+			continue
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName())
+
+		smpl := &model.Sample{
+			Metric: model.Metric(lset),
+			Value:  model.SampleValue(m.Gauge.GetValue()),
+		}
+
+		if m.TimestampMs != nil {
+			smpl.Timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		} else {
+			smpl.Timestamp = o.Timestamp
+		}
+
+		samples = append(samples, smpl)
+	}
+
+	return samples
+}
+
+func extractUntyped(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Untyped == nil {
+			continue
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName())
+
+		smpl := &model.Sample{
+			Metric: model.Metric(lset),
+			Value:  model.SampleValue(m.Untyped.GetValue()),
+		}
+
+		if m.TimestampMs != nil {
+			smpl.Timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		} else {
+			smpl.Timestamp = o.Timestamp
+		}
+
+		samples = append(samples, smpl)
+	}
+
+	return samples
+}
+
+func extractSummary(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Summary == nil {
+			continue
+		}
+
+		timestamp := o.Timestamp
+		if m.TimestampMs != nil {
+			timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		}
+
+		for _, q := range m.Summary.Quantile {
+			lset := make(model.LabelSet, len(m.Label)+2)
+			for _, p := range m.Label {
+				lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+			}
+			// BUG(matt): Update other names to "quantile".
+			lset[model.LabelName(model.QuantileLabel)] = model.LabelValue(fmt.Sprint(q.GetQuantile()))
+			lset[model.MetricNameLabel] = model.LabelValue(f.GetName())
+
+			samples = append(samples, &model.Sample{
+				Metric:    model.Metric(lset),
+				Value:     model.SampleValue(q.GetValue()),
+				Timestamp: timestamp,
+			})
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_sum")
+
+		samples = append(samples, &model.Sample{
+			Metric:    model.Metric(lset),
+			Value:     model.SampleValue(m.Summary.GetSampleSum()),
+			Timestamp: timestamp,
+		})
+
+		lset = make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_count")
+
+		samples = append(samples, &model.Sample{
+			Metric:    model.Metric(lset),
+			Value:     model.SampleValue(m.Summary.GetSampleCount()),
+			Timestamp: timestamp,
+		})
+	}
+
+	return samples
+}
+
+func extractHistogram(o *DecodeOptions, f *dto.MetricFamily) model.Vector {
+	samples := make(model.Vector, 0, len(f.Metric))
+
+	for _, m := range f.Metric {
+		if m.Histogram == nil {
+			continue
+		}
+
+		timestamp := o.Timestamp
+		if m.TimestampMs != nil {
+			timestamp = model.TimeFromUnixNano(*m.TimestampMs * 1000000)
+		}
+
+		infSeen := false
+
+		for _, q := range m.Histogram.Bucket {
+			lset := make(model.LabelSet, len(m.Label)+2)
+			for _, p := range m.Label {
+				lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+			}
+			lset[model.LabelName(model.BucketLabel)] = model.LabelValue(fmt.Sprint(q.GetUpperBound()))
+			lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_bucket")
+
+			if math.IsInf(q.GetUpperBound(), +1) {
+				infSeen = true
+			}
+
+			samples = append(samples, &model.Sample{
+				Metric:    model.Metric(lset),
+				Value:     model.SampleValue(q.GetCumulativeCount()),
+				Timestamp: timestamp,
+			})
+		}
+
+		lset := make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_sum")
+
+		samples = append(samples, &model.Sample{
+			Metric:    model.Metric(lset),
+			Value:     model.SampleValue(m.Histogram.GetSampleSum()),
+			Timestamp: timestamp,
+		})
+
+		lset = make(model.LabelSet, len(m.Label)+1)
+		for _, p := range m.Label {
+			lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+		}
+		lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_count")
+
+		count := &model.Sample{
+			Metric:    model.Metric(lset),
+			Value:     model.SampleValue(m.Histogram.GetSampleCount()),
+			Timestamp: timestamp,
+		}
+		samples = append(samples, count)
+
+		if !infSeen {
+			// Append an infinity bucket sample.
+			lset := make(model.LabelSet, len(m.Label)+2)
+			for _, p := range m.Label {
+				lset[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+			}
+			lset[model.LabelName(model.BucketLabel)] = model.LabelValue("+Inf")
+			lset[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_bucket")
+
+			samples = append(samples, &model.Sample{
+				Metric:    model.Metric(lset),
+				Value:     count.Value,
+				Timestamp: timestamp,
+			})
+		}
+	}
+
+	return samples
+}

vendor/github.com/prometheus/common/expfmt/encode.go

@@ -0,0 +1,88 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/matttproud/golang_protobuf_extensions/pbutil"
+	"github.com/prometheus/common/internal/bitbucket.org/ww/goautoneg"
+
+	dto "github.com/prometheus/client_model/go"
+)
+
+// Encoder types encode metric families into an underlying wire protocol.
+type Encoder interface {
+	Encode(*dto.MetricFamily) error
+}
+
+type encoder func(*dto.MetricFamily) error
+
+func (e encoder) Encode(v *dto.MetricFamily) error {
+	return e(v)
+}
+
+// Negotiate returns the Content-Type based on the given Accept header.
+// If no appropriate accepted type is found, FmtText is returned.
+func Negotiate(h http.Header) Format {
+	for _, ac := range goautoneg.ParseAccept(h.Get(hdrAccept)) {
+		// Check for protocol buffer
+		if ac.Type+"/"+ac.SubType == ProtoType && ac.Params["proto"] == ProtoProtocol {
+			switch ac.Params["encoding"] {
+			case "delimited":
+				return FmtProtoDelim
+			case "text":
+				return FmtProtoText
+			case "compact-text":
+				return FmtProtoCompact
+			}
+		}
+		// Check for text format.
+		ver := ac.Params["version"]
+		if ac.Type == "text" && ac.SubType == "plain" && (ver == TextVersion || ver == "") {
+			return FmtText
+		}
+	}
+	return FmtText
+}
+
+// NewEncoder returns a new encoder based on content type negotiation.
+func NewEncoder(w io.Writer, format Format) Encoder {
+	switch format {
+	case FmtProtoDelim:
+		return encoder(func(v *dto.MetricFamily) error {
+			_, err := pbutil.WriteDelimited(w, v)
+			return err
+		})
+	case FmtProtoCompact:
+		return encoder(func(v *dto.MetricFamily) error {
+			_, err := fmt.Fprintln(w, v.String())
+			return err
+		})
+	case FmtProtoText:
+		return encoder(func(v *dto.MetricFamily) error {
+			_, err := fmt.Fprintln(w, proto.MarshalTextString(v))
+			return err
+		})
+	case FmtText:
+		return encoder(func(v *dto.MetricFamily) error {
+			_, err := MetricFamilyToText(w, v)
+			return err
+		})
+	}
+	panic("expfmt.NewEncoder: unknown format")
+}

vendor/github.com/prometheus/common/expfmt/expfmt.go

@@ -0,0 +1,38 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package expfmt contains tools for reading and writing Prometheus metrics.
+package expfmt
+
+// Format specifies the HTTP content type of the different wire protocols.
+type Format string
+
+// Constants to assemble the Content-Type values for the different wire protocols.
+const (
+	TextVersion   = "0.0.4"
+	ProtoType     = `application/vnd.google.protobuf`
+	ProtoProtocol = `io.prometheus.client.MetricFamily`
+	ProtoFmt      = ProtoType + "; proto=" + ProtoProtocol + ";"
+
+	// The Content-Type values for the different wire protocols.
+	FmtUnknown      Format = `<unknown>`
+	FmtText         Format = `text/plain; version=` + TextVersion + `; charset=utf-8`
+	FmtProtoDelim   Format = ProtoFmt + ` encoding=delimited`
+	FmtProtoText    Format = ProtoFmt + ` encoding=text`
+	FmtProtoCompact Format = ProtoFmt + ` encoding=compact-text`
+)
+
+const (
+	hdrContentType = "Content-Type"
+	hdrAccept      = "Accept"
+)

vendor/github.com/prometheus/common/expfmt/fuzz.go

@@ -0,0 +1,36 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Build only when actually fuzzing
+// +build gofuzz
+
+package expfmt
+
+import "bytes"
+
+// Fuzz text metric parser with with github.com/dvyukov/go-fuzz:
+//
+//     go-fuzz-build github.com/prometheus/common/expfmt
+//     go-fuzz -bin expfmt-fuzz.zip -workdir fuzz
+//
+// Further input samples should go in the folder fuzz/corpus.
+func Fuzz(in []byte) int {
+	parser := TextParser{}
+	_, err := parser.TextToMetricFamilies(bytes.NewReader(in))
+
+	if err != nil {
+		return 0
+	}
+
+	return 1
+}

vendor/github.com/prometheus/common/expfmt/text_create.go

@@ -0,0 +1,303 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"fmt"
+	"io"
+	"math"
+	"strings"
+
+	dto "github.com/prometheus/client_model/go"
+	"github.com/prometheus/common/model"
+)
+
+// MetricFamilyToText converts a MetricFamily proto message into text format and
+// writes the resulting lines to 'out'. It returns the number of bytes written
+// and any error encountered. The output will have the same order as the input,
+// no further sorting is performed. Furthermore, this function assumes the input
+// is already sanitized and does not perform any sanity checks. If the input
+// contains duplicate metrics or invalid metric or label names, the conversion
+// will result in invalid text format output.
+//
+// This method fulfills the type 'prometheus.encoder'.
+func MetricFamilyToText(out io.Writer, in *dto.MetricFamily) (int, error) {
+	var written int
+
+	// Fail-fast checks.
+	if len(in.Metric) == 0 {
+		return written, fmt.Errorf("MetricFamily has no metrics: %s", in)
+	}
+	name := in.GetName()
+	if name == "" {
+		return written, fmt.Errorf("MetricFamily has no name: %s", in)
+	}
+
+	// Comments, first HELP, then TYPE.
+	if in.Help != nil {
+		n, err := fmt.Fprintf(
+			out, "# HELP %s %s\n",
+			name, escapeString(*in.Help, false),
+		)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	metricType := in.GetType()
+	n, err := fmt.Fprintf(
+		out, "# TYPE %s %s\n",
+		name, strings.ToLower(metricType.String()),
+	)
+	written += n
+	if err != nil {
+		return written, err
+	}
+
+	// Finally the samples, one line for each.
+	for _, metric := range in.Metric {
+		switch metricType {
+		case dto.MetricType_COUNTER:
+			if metric.Counter == nil {
+				return written, fmt.Errorf(
+					"expected counter in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeSample(
+				name, metric, "", "",
+				metric.Counter.GetValue(),
+				out,
+			)
+		case dto.MetricType_GAUGE:
+			if metric.Gauge == nil {
+				return written, fmt.Errorf(
+					"expected gauge in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeSample(
+				name, metric, "", "",
+				metric.Gauge.GetValue(),
+				out,
+			)
+		case dto.MetricType_UNTYPED:
+			if metric.Untyped == nil {
+				return written, fmt.Errorf(
+					"expected untyped in metric %s %s", name, metric,
+				)
+			}
+			n, err = writeSample(
+				name, metric, "", "",
+				metric.Untyped.GetValue(),
+				out,
+			)
+		case dto.MetricType_SUMMARY:
+			if metric.Summary == nil {
+				return written, fmt.Errorf(
+					"expected summary in metric %s %s", name, metric,
+				)
+			}
+			for _, q := range metric.Summary.Quantile {
+				n, err = writeSample(
+					name, metric,
+					model.QuantileLabel, fmt.Sprint(q.GetQuantile()),
+					q.GetValue(),
+					out,
+				)
+				written += n
+				if err != nil {
+					return written, err
+				}
+			}
+			n, err = writeSample(
+				name+"_sum", metric, "", "",
+				metric.Summary.GetSampleSum(),
+				out,
+			)
+			if err != nil {
+				return written, err
+			}
+			written += n
+			n, err = writeSample(
+				name+"_count", metric, "", "",
+				float64(metric.Summary.GetSampleCount()),
+				out,
+			)
+		case dto.MetricType_HISTOGRAM:
+			if metric.Histogram == nil {
+				return written, fmt.Errorf(
+					"expected histogram in metric %s %s", name, metric,
+				)
+			}
+			infSeen := false
+			for _, q := range metric.Histogram.Bucket {
+				n, err = writeSample(
+					name+"_bucket", metric,
+					model.BucketLabel, fmt.Sprint(q.GetUpperBound()),
+					float64(q.GetCumulativeCount()),
+					out,
+				)
+				written += n
+				if err != nil {
+					return written, err
+				}
+				if math.IsInf(q.GetUpperBound(), +1) {
+					infSeen = true
+				}
+			}
+			if !infSeen {
+				n, err = writeSample(
+					name+"_bucket", metric,
+					model.BucketLabel, "+Inf",
+					float64(metric.Histogram.GetSampleCount()),
+					out,
+				)
+				if err != nil {
+					return written, err
+				}
+				written += n
+			}
+			n, err = writeSample(
+				name+"_sum", metric, "", "",
+				metric.Histogram.GetSampleSum(),
+				out,
+			)
+			if err != nil {
+				return written, err
+			}
+			written += n
+			n, err = writeSample(
+				name+"_count", metric, "", "",
+				float64(metric.Histogram.GetSampleCount()),
+				out,
+			)
+		default:
+			return written, fmt.Errorf(
+				"unexpected type in metric %s %s", name, metric,
+			)
+		}
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	return written, nil
+}
+
+// writeSample writes a single sample in text format to out, given the metric
+// name, the metric proto message itself, optionally an additional label name
+// and value (use empty strings if not required), and the value. The function
+// returns the number of bytes written and any error encountered.
+func writeSample(
+	name string,
+	metric *dto.Metric,
+	additionalLabelName, additionalLabelValue string,
+	value float64,
+	out io.Writer,
+) (int, error) {
+	var written int
+	n, err := fmt.Fprint(out, name)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	n, err = labelPairsToText(
+		metric.Label,
+		additionalLabelName, additionalLabelValue,
+		out,
+	)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	n, err = fmt.Fprintf(out, " %v", value)
+	written += n
+	if err != nil {
+		return written, err
+	}
+	if metric.TimestampMs != nil {
+		n, err = fmt.Fprintf(out, " %v", *metric.TimestampMs)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	n, err = out.Write([]byte{'\n'})
+	written += n
+	if err != nil {
+		return written, err
+	}
+	return written, nil
+}
+
+// labelPairsToText converts a slice of LabelPair proto messages plus the
+// explicitly given additional label pair into text formatted as required by the
+// text format and writes it to 'out'. An empty slice in combination with an
+// empty string 'additionalLabelName' results in nothing being
+// written. Otherwise, the label pairs are written, escaped as required by the
+// text format, and enclosed in '{...}'. The function returns the number of
+// bytes written and any error encountered.
+func labelPairsToText(
+	in []*dto.LabelPair,
+	additionalLabelName, additionalLabelValue string,
+	out io.Writer,
+) (int, error) {
+	if len(in) == 0 && additionalLabelName == "" {
+		return 0, nil
+	}
+	var written int
+	separator := '{'
+	for _, lp := range in {
+		n, err := fmt.Fprintf(
+			out, `%c%s="%s"`,
+			separator, lp.GetName(), escapeString(lp.GetValue(), true),
+		)
+		written += n
+		if err != nil {
+			return written, err
+		}
+		separator = ','
+	}
+	if additionalLabelName != "" {
+		n, err := fmt.Fprintf(
+			out, `%c%s="%s"`,
+			separator, additionalLabelName,
+			escapeString(additionalLabelValue, true),
+		)
+		written += n
+		if err != nil {
+			return written, err
+		}
+	}
+	n, err := out.Write([]byte{'}'})
+	written += n
+	if err != nil {
+		return written, err
+	}
+	return written, nil
+}
+
+var (
+	escape                = strings.NewReplacer("\\", `\\`, "\n", `\n`)
+	escapeWithDoubleQuote = strings.NewReplacer("\\", `\\`, "\n", `\n`, "\"", `\"`)
+)
+
+// escapeString replaces '\' by '\\', new line character by '\n', and - if
+// includeDoubleQuote is true - '"' by '\"'.
+func escapeString(v string, includeDoubleQuote bool) string {
+	if includeDoubleQuote {
+		return escapeWithDoubleQuote.Replace(v)
+	}
+
+	return escape.Replace(v)
+}

vendor/github.com/prometheus/common/expfmt/text_parse.go

@@ -0,0 +1,757 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package expfmt
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"math"
+	"strconv"
+	"strings"
+
+	dto "github.com/prometheus/client_model/go"
+
+	"github.com/golang/protobuf/proto"
+	"github.com/prometheus/common/model"
+)
+
+// A stateFn is a function that represents a state in a state machine. By
+// executing it, the state is progressed to the next state. The stateFn returns
+// another stateFn, which represents the new state. The end state is represented
+// by nil.
+type stateFn func() stateFn
+
+// ParseError signals errors while parsing the simple and flat text-based
+// exchange format.
+type ParseError struct {
+	Line int
+	Msg  string
+}
+
+// Error implements the error interface.
+func (e ParseError) Error() string {
+	return fmt.Sprintf("text format parsing error in line %d: %s", e.Line, e.Msg)
+}
+
+// TextParser is used to parse the simple and flat text-based exchange format. Its
+// zero value is ready to use.
+type TextParser struct {
+	metricFamiliesByName map[string]*dto.MetricFamily
+	buf                  *bufio.Reader // Where the parsed input is read through.
+	err                  error         // Most recent error.
+	lineCount            int           // Tracks the line count for error messages.
+	currentByte          byte          // The most recent byte read.
+	currentToken         bytes.Buffer  // Re-used each time a token has to be gathered from multiple bytes.
+	currentMF            *dto.MetricFamily
+	currentMetric        *dto.Metric
+	currentLabelPair     *dto.LabelPair
+
+	// The remaining member variables are only used for summaries/histograms.
+	currentLabels map[string]string // All labels including '__name__' but excluding 'quantile'/'le'
+	// Summary specific.
+	summaries       map[uint64]*dto.Metric // Key is created with LabelsToSignature.
+	currentQuantile float64
+	// Histogram specific.
+	histograms    map[uint64]*dto.Metric // Key is created with LabelsToSignature.
+	currentBucket float64
+	// These tell us if the currently processed line ends on '_count' or
+	// '_sum' respectively and belong to a summary/histogram, representing the sample
+	// count and sum of that summary/histogram.
+	currentIsSummaryCount, currentIsSummarySum     bool
+	currentIsHistogramCount, currentIsHistogramSum bool
+}
+
+// TextToMetricFamilies reads 'in' as the simple and flat text-based exchange
+// format and creates MetricFamily proto messages. It returns the MetricFamily
+// proto messages in a map where the metric names are the keys, along with any
+// error encountered.
+//
+// If the input contains duplicate metrics (i.e. lines with the same metric name
+// and exactly the same label set), the resulting MetricFamily will contain
+// duplicate Metric proto messages. Similar is true for duplicate label
+// names. Checks for duplicates have to be performed separately, if required.
+// Also note that neither the metrics within each MetricFamily are sorted nor
+// the label pairs within each Metric. Sorting is not required for the most
+// frequent use of this method, which is sample ingestion in the Prometheus
+// server. However, for presentation purposes, you might want to sort the
+// metrics, and in some cases, you must sort the labels, e.g. for consumption by
+// the metric family injection hook of the Prometheus registry.
+//
+// Summaries and histograms are rather special beasts. You would probably not
+// use them in the simple text format anyway. This method can deal with
+// summaries and histograms if they are presented in exactly the way the
+// text.Create function creates them.
+//
+// This method must not be called concurrently. If you want to parse different
+// input concurrently, instantiate a separate Parser for each goroutine.
+func (p *TextParser) TextToMetricFamilies(in io.Reader) (map[string]*dto.MetricFamily, error) {
+	p.reset(in)
+	for nextState := p.startOfLine; nextState != nil; nextState = nextState() {
+		// Magic happens here...
+	}
+	// Get rid of empty metric families.
+	for k, mf := range p.metricFamiliesByName {
+		if len(mf.GetMetric()) == 0 {
+			delete(p.metricFamiliesByName, k)
+		}
+	}
+	// If p.err is io.EOF now, we have run into a premature end of the input
+	// stream. Turn this error into something nicer and more
+	// meaningful. (io.EOF is often used as a signal for the legitimate end
+	// of an input stream.)
+	if p.err == io.EOF {
+		p.parseError("unexpected end of input stream")
+	}
+	return p.metricFamiliesByName, p.err
+}
+
+func (p *TextParser) reset(in io.Reader) {
+	p.metricFamiliesByName = map[string]*dto.MetricFamily{}
+	if p.buf == nil {
+		p.buf = bufio.NewReader(in)
+	} else {
+		p.buf.Reset(in)
+	}
+	p.err = nil
+	p.lineCount = 0
+	if p.summaries == nil || len(p.summaries) > 0 {
+		p.summaries = map[uint64]*dto.Metric{}
+	}
+	if p.histograms == nil || len(p.histograms) > 0 {
+		p.histograms = map[uint64]*dto.Metric{}
+	}
+	p.currentQuantile = math.NaN()
+	p.currentBucket = math.NaN()
+}
+
+// startOfLine represents the state where the next byte read from p.buf is the
+// start of a line (or whitespace leading up to it).
+func (p *TextParser) startOfLine() stateFn {
+	p.lineCount++
+	if p.skipBlankTab(); p.err != nil {
+		// End of input reached. This is the only case where
+		// that is not an error but a signal that we are done.
+		p.err = nil
+		return nil
+	}
+	switch p.currentByte {
+	case '#':
+		return p.startComment
+	case '\n':
+		return p.startOfLine // Empty line, start the next one.
+	}
+	return p.readingMetricName
+}
+
+// startComment represents the state where the next byte read from p.buf is the
+// start of a comment (or whitespace leading up to it).
+func (p *TextParser) startComment() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '\n' {
+		return p.startOfLine
+	}
+	if p.readTokenUntilWhitespace(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	// If we have hit the end of line already, there is nothing left
+	// to do. This is not considered a syntax error.
+	if p.currentByte == '\n' {
+		return p.startOfLine
+	}
+	keyword := p.currentToken.String()
+	if keyword != "HELP" && keyword != "TYPE" {
+		// Generic comment, ignore by fast forwarding to end of line.
+		for p.currentByte != '\n' {
+			if p.currentByte, p.err = p.buf.ReadByte(); p.err != nil {
+				return nil // Unexpected end of input.
+			}
+		}
+		return p.startOfLine
+	}
+	// There is something. Next has to be a metric name.
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.readTokenAsMetricName(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '\n' {
+		// At the end of the line already.
+		// Again, this is not considered a syntax error.
+		return p.startOfLine
+	}
+	if !isBlankOrTab(p.currentByte) {
+		p.parseError("invalid metric name in comment")
+		return nil
+	}
+	p.setOrCreateCurrentMF()
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '\n' {
+		// At the end of the line already.
+		// Again, this is not considered a syntax error.
+		return p.startOfLine
+	}
+	switch keyword {
+	case "HELP":
+		return p.readingHelp
+	case "TYPE":
+		return p.readingType
+	}
+	panic(fmt.Sprintf("code error: unexpected keyword %q", keyword))
+}
+
+// readingMetricName represents the state where the last byte read (now in
+// p.currentByte) is the first byte of a metric name.
+func (p *TextParser) readingMetricName() stateFn {
+	if p.readTokenAsMetricName(); p.err != nil {
+		return nil
+	}
+	if p.currentToken.Len() == 0 {
+		p.parseError("invalid metric name")
+		return nil
+	}
+	p.setOrCreateCurrentMF()
+	// Now is the time to fix the type if it hasn't happened yet.
+	if p.currentMF.Type == nil {
+		p.currentMF.Type = dto.MetricType_UNTYPED.Enum()
+	}
+	p.currentMetric = &dto.Metric{}
+	// Do not append the newly created currentMetric to
+	// currentMF.Metric right now. First wait if this is a summary,
+	// and the metric exists already, which we can only know after
+	// having read all the labels.
+	if p.skipBlankTabIfCurrentBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	return p.readingLabels
+}
+
+// readingLabels represents the state where the last byte read (now in
+// p.currentByte) is either the first byte of the label set (i.e. a '{'), or the
+// first byte of the value (otherwise).
+func (p *TextParser) readingLabels() stateFn {
+	// Summaries/histograms are special. We have to reset the
+	// currentLabels map, currentQuantile and currentBucket before starting to
+	// read labels.
+	if p.currentMF.GetType() == dto.MetricType_SUMMARY || p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+		p.currentLabels = map[string]string{}
+		p.currentLabels[string(model.MetricNameLabel)] = p.currentMF.GetName()
+		p.currentQuantile = math.NaN()
+		p.currentBucket = math.NaN()
+	}
+	if p.currentByte != '{' {
+		return p.readingValue
+	}
+	return p.startLabelName
+}
+
+// startLabelName represents the state where the next byte read from p.buf is
+// the start of a label name (or whitespace leading up to it).
+func (p *TextParser) startLabelName() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte == '}' {
+		if p.skipBlankTab(); p.err != nil {
+			return nil // Unexpected end of input.
+		}
+		return p.readingValue
+	}
+	if p.readTokenAsLabelName(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentToken.Len() == 0 {
+		p.parseError(fmt.Sprintf("invalid label name for metric %q", p.currentMF.GetName()))
+		return nil
+	}
+	p.currentLabelPair = &dto.LabelPair{Name: proto.String(p.currentToken.String())}
+	if p.currentLabelPair.GetName() == string(model.MetricNameLabel) {
+		p.parseError(fmt.Sprintf("label name %q is reserved", model.MetricNameLabel))
+		return nil
+	}
+	// Special summary/histogram treatment. Don't add 'quantile' and 'le'
+	// labels to 'real' labels.
+	if !(p.currentMF.GetType() == dto.MetricType_SUMMARY && p.currentLabelPair.GetName() == model.QuantileLabel) &&
+		!(p.currentMF.GetType() == dto.MetricType_HISTOGRAM && p.currentLabelPair.GetName() == model.BucketLabel) {
+		p.currentMetric.Label = append(p.currentMetric.Label, p.currentLabelPair)
+	}
+	if p.skipBlankTabIfCurrentBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte != '=' {
+		p.parseError(fmt.Sprintf("expected '=' after label name, found %q", p.currentByte))
+		return nil
+	}
+	return p.startLabelValue
+}
+
+// startLabelValue represents the state where the next byte read from p.buf is
+// the start of a (quoted) label value (or whitespace leading up to it).
+func (p *TextParser) startLabelValue() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentByte != '"' {
+		p.parseError(fmt.Sprintf("expected '\"' at start of label value, found %q", p.currentByte))
+		return nil
+	}
+	if p.readTokenAsLabelValue(); p.err != nil {
+		return nil
+	}
+	if !model.LabelValue(p.currentToken.String()).IsValid() {
+		p.parseError(fmt.Sprintf("invalid label value %q", p.currentToken.String()))
+		return nil
+	}
+	p.currentLabelPair.Value = proto.String(p.currentToken.String())
+	// Special treatment of summaries:
+	// - Quantile labels are special, will result in dto.Quantile later.
+	// - Other labels have to be added to currentLabels for signature calculation.
+	if p.currentMF.GetType() == dto.MetricType_SUMMARY {
+		if p.currentLabelPair.GetName() == model.QuantileLabel {
+			if p.currentQuantile, p.err = strconv.ParseFloat(p.currentLabelPair.GetValue(), 64); p.err != nil {
+				// Create a more helpful error message.
+				p.parseError(fmt.Sprintf("expected float as value for 'quantile' label, got %q", p.currentLabelPair.GetValue()))
+				return nil
+			}
+		} else {
+			p.currentLabels[p.currentLabelPair.GetName()] = p.currentLabelPair.GetValue()
+		}
+	}
+	// Similar special treatment of histograms.
+	if p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+		if p.currentLabelPair.GetName() == model.BucketLabel {
+			if p.currentBucket, p.err = strconv.ParseFloat(p.currentLabelPair.GetValue(), 64); p.err != nil {
+				// Create a more helpful error message.
+				p.parseError(fmt.Sprintf("expected float as value for 'le' label, got %q", p.currentLabelPair.GetValue()))
+				return nil
+			}
+		} else {
+			p.currentLabels[p.currentLabelPair.GetName()] = p.currentLabelPair.GetValue()
+		}
+	}
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	switch p.currentByte {
+	case ',':
+		return p.startLabelName
+
+	case '}':
+		if p.skipBlankTab(); p.err != nil {
+			return nil // Unexpected end of input.
+		}
+		return p.readingValue
+	default:
+		p.parseError(fmt.Sprintf("unexpected end of label value %q", p.currentLabelPair.Value))
+		return nil
+	}
+}
+
+// readingValue represents the state where the last byte read (now in
+// p.currentByte) is the first byte of the sample value (i.e. a float).
+func (p *TextParser) readingValue() stateFn {
+	// When we are here, we have read all the labels, so for the
+	// special case of a summary/histogram, we can finally find out
+	// if the metric already exists.
+	if p.currentMF.GetType() == dto.MetricType_SUMMARY {
+		signature := model.LabelsToSignature(p.currentLabels)
+		if summary := p.summaries[signature]; summary != nil {
+			p.currentMetric = summary
+		} else {
+			p.summaries[signature] = p.currentMetric
+			p.currentMF.Metric = append(p.currentMF.Metric, p.currentMetric)
+		}
+	} else if p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+		signature := model.LabelsToSignature(p.currentLabels)
+		if histogram := p.histograms[signature]; histogram != nil {
+			p.currentMetric = histogram
+		} else {
+			p.histograms[signature] = p.currentMetric
+			p.currentMF.Metric = append(p.currentMF.Metric, p.currentMetric)
+		}
+	} else {
+		p.currentMF.Metric = append(p.currentMF.Metric, p.currentMetric)
+	}
+	if p.readTokenUntilWhitespace(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	value, err := strconv.ParseFloat(p.currentToken.String(), 64)
+	if err != nil {
+		// Create a more helpful error message.
+		p.parseError(fmt.Sprintf("expected float as value, got %q", p.currentToken.String()))
+		return nil
+	}
+	switch p.currentMF.GetType() {
+	case dto.MetricType_COUNTER:
+		p.currentMetric.Counter = &dto.Counter{Value: proto.Float64(value)}
+	case dto.MetricType_GAUGE:
+		p.currentMetric.Gauge = &dto.Gauge{Value: proto.Float64(value)}
+	case dto.MetricType_UNTYPED:
+		p.currentMetric.Untyped = &dto.Untyped{Value: proto.Float64(value)}
+	case dto.MetricType_SUMMARY:
+		// *sigh*
+		if p.currentMetric.Summary == nil {
+			p.currentMetric.Summary = &dto.Summary{}
+		}
+		switch {
+		case p.currentIsSummaryCount:
+			p.currentMetric.Summary.SampleCount = proto.Uint64(uint64(value))
+		case p.currentIsSummarySum:
+			p.currentMetric.Summary.SampleSum = proto.Float64(value)
+		case !math.IsNaN(p.currentQuantile):
+			p.currentMetric.Summary.Quantile = append(
+				p.currentMetric.Summary.Quantile,
+				&dto.Quantile{
+					Quantile: proto.Float64(p.currentQuantile),
+					Value:    proto.Float64(value),
+				},
+			)
+		}
+	case dto.MetricType_HISTOGRAM:
+		// *sigh*
+		if p.currentMetric.Histogram == nil {
+			p.currentMetric.Histogram = &dto.Histogram{}
+		}
+		switch {
+		case p.currentIsHistogramCount:
+			p.currentMetric.Histogram.SampleCount = proto.Uint64(uint64(value))
+		case p.currentIsHistogramSum:
+			p.currentMetric.Histogram.SampleSum = proto.Float64(value)
+		case !math.IsNaN(p.currentBucket):
+			p.currentMetric.Histogram.Bucket = append(
+				p.currentMetric.Histogram.Bucket,
+				&dto.Bucket{
+					UpperBound:      proto.Float64(p.currentBucket),
+					CumulativeCount: proto.Uint64(uint64(value)),
+				},
+			)
+		}
+	default:
+		p.err = fmt.Errorf("unexpected type for metric name %q", p.currentMF.GetName())
+	}
+	if p.currentByte == '\n' {
+		return p.startOfLine
+	}
+	return p.startTimestamp
+}
+
+// startTimestamp represents the state where the next byte read from p.buf is
+// the start of the timestamp (or whitespace leading up to it).
+func (p *TextParser) startTimestamp() stateFn {
+	if p.skipBlankTab(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.readTokenUntilWhitespace(); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	timestamp, err := strconv.ParseInt(p.currentToken.String(), 10, 64)
+	if err != nil {
+		// Create a more helpful error message.
+		p.parseError(fmt.Sprintf("expected integer as timestamp, got %q", p.currentToken.String()))
+		return nil
+	}
+	p.currentMetric.TimestampMs = proto.Int64(timestamp)
+	if p.readTokenUntilNewline(false); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	if p.currentToken.Len() > 0 {
+		p.parseError(fmt.Sprintf("spurious string after timestamp: %q", p.currentToken.String()))
+		return nil
+	}
+	return p.startOfLine
+}
+
+// readingHelp represents the state where the last byte read (now in
+// p.currentByte) is the first byte of the docstring after 'HELP'.
+func (p *TextParser) readingHelp() stateFn {
+	if p.currentMF.Help != nil {
+		p.parseError(fmt.Sprintf("second HELP line for metric name %q", p.currentMF.GetName()))
+		return nil
+	}
+	// Rest of line is the docstring.
+	if p.readTokenUntilNewline(true); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	p.currentMF.Help = proto.String(p.currentToken.String())
+	return p.startOfLine
+}
+
+// readingType represents the state where the last byte read (now in
+// p.currentByte) is the first byte of the type hint after 'HELP'.
+func (p *TextParser) readingType() stateFn {
+	if p.currentMF.Type != nil {
+		p.parseError(fmt.Sprintf("second TYPE line for metric name %q, or TYPE reported after samples", p.currentMF.GetName()))
+		return nil
+	}
+	// Rest of line is the type.
+	if p.readTokenUntilNewline(false); p.err != nil {
+		return nil // Unexpected end of input.
+	}
+	metricType, ok := dto.MetricType_value[strings.ToUpper(p.currentToken.String())]
+	if !ok {
+		p.parseError(fmt.Sprintf("unknown metric type %q", p.currentToken.String()))
+		return nil
+	}
+	p.currentMF.Type = dto.MetricType(metricType).Enum()
+	return p.startOfLine
+}
+
+// parseError sets p.err to a ParseError at the current line with the given
+// message.
+func (p *TextParser) parseError(msg string) {
+	p.err = ParseError{
+		Line: p.lineCount,
+		Msg:  msg,
+	}
+}
+
+// skipBlankTab reads (and discards) bytes from p.buf until it encounters a byte
+// that is neither ' ' nor '\t'. That byte is left in p.currentByte.
+func (p *TextParser) skipBlankTab() {
+	for {
+		if p.currentByte, p.err = p.buf.ReadByte(); p.err != nil || !isBlankOrTab(p.currentByte) {
+			return
+		}
+	}
+}
+
+// skipBlankTabIfCurrentBlankTab works exactly as skipBlankTab but doesn't do
+// anything if p.currentByte is neither ' ' nor '\t'.
+func (p *TextParser) skipBlankTabIfCurrentBlankTab() {
+	if isBlankOrTab(p.currentByte) {
+		p.skipBlankTab()
+	}
+}
+
+// readTokenUntilWhitespace copies bytes from p.buf into p.currentToken.  The
+// first byte considered is the byte already read (now in p.currentByte).  The
+// first whitespace byte encountered is still copied into p.currentByte, but not
+// into p.currentToken.
+func (p *TextParser) readTokenUntilWhitespace() {
+	p.currentToken.Reset()
+	for p.err == nil && !isBlankOrTab(p.currentByte) && p.currentByte != '\n' {
+		p.currentToken.WriteByte(p.currentByte)
+		p.currentByte, p.err = p.buf.ReadByte()
+	}
+}
+
+// readTokenUntilNewline copies bytes from p.buf into p.currentToken.  The first
+// byte considered is the byte already read (now in p.currentByte).  The first
+// newline byte encountered is still copied into p.currentByte, but not into
+// p.currentToken. If recognizeEscapeSequence is true, two escape sequences are
+// recognized: '\\' translates into '\', and '\n' into a line-feed character.
+// All other escape sequences are invalid and cause an error.
+func (p *TextParser) readTokenUntilNewline(recognizeEscapeSequence bool) {
+	p.currentToken.Reset()
+	escaped := false
+	for p.err == nil {
+		if recognizeEscapeSequence && escaped {
+			switch p.currentByte {
+			case '\\':
+				p.currentToken.WriteByte(p.currentByte)
+			case 'n':
+				p.currentToken.WriteByte('\n')
+			default:
+				p.parseError(fmt.Sprintf("invalid escape sequence '\\%c'", p.currentByte))
+				return
+			}
+			escaped = false
+		} else {
+			switch p.currentByte {
+			case '\n':
+				return
+			case '\\':
+				escaped = true
+			default:
+				p.currentToken.WriteByte(p.currentByte)
+			}
+		}
+		p.currentByte, p.err = p.buf.ReadByte()
+	}
+}
+
+// readTokenAsMetricName copies a metric name from p.buf into p.currentToken.
+// The first byte considered is the byte already read (now in p.currentByte).
+// The first byte not part of a metric name is still copied into p.currentByte,
+// but not into p.currentToken.
+func (p *TextParser) readTokenAsMetricName() {
+	p.currentToken.Reset()
+	if !isValidMetricNameStart(p.currentByte) {
+		return
+	}
+	for {
+		p.currentToken.WriteByte(p.currentByte)
+		p.currentByte, p.err = p.buf.ReadByte()
+		if p.err != nil || !isValidMetricNameContinuation(p.currentByte) {
+			return
+		}
+	}
+}
+
+// readTokenAsLabelName copies a label name from p.buf into p.currentToken.
+// The first byte considered is the byte already read (now in p.currentByte).
+// The first byte not part of a label name is still copied into p.currentByte,
+// but not into p.currentToken.
+func (p *TextParser) readTokenAsLabelName() {
+	p.currentToken.Reset()
+	if !isValidLabelNameStart(p.currentByte) {
+		return
+	}
+	for {
+		p.currentToken.WriteByte(p.currentByte)
+		p.currentByte, p.err = p.buf.ReadByte()
+		if p.err != nil || !isValidLabelNameContinuation(p.currentByte) {
+			return
+		}
+	}
+}
+
+// readTokenAsLabelValue copies a label value from p.buf into p.currentToken.
+// In contrast to the other 'readTokenAs...' functions, which start with the
+// last read byte in p.currentByte, this method ignores p.currentByte and starts
+// with reading a new byte from p.buf. The first byte not part of a label value
+// is still copied into p.currentByte, but not into p.currentToken.
+func (p *TextParser) readTokenAsLabelValue() {
+	p.currentToken.Reset()
+	escaped := false
+	for {
+		if p.currentByte, p.err = p.buf.ReadByte(); p.err != nil {
+			return
+		}
+		if escaped {
+			switch p.currentByte {
+			case '"', '\\':
+				p.currentToken.WriteByte(p.currentByte)
+			case 'n':
+				p.currentToken.WriteByte('\n')
+			default:
+				p.parseError(fmt.Sprintf("invalid escape sequence '\\%c'", p.currentByte))
+				return
+			}
+			escaped = false
+			continue
+		}
+		switch p.currentByte {
+		case '"':
+			return
+		case '\n':
+			p.parseError(fmt.Sprintf("label value %q contains unescaped new-line", p.currentToken.String()))
+			return
+		case '\\':
+			escaped = true
+		default:
+			p.currentToken.WriteByte(p.currentByte)
+		}
+	}
+}
+
+func (p *TextParser) setOrCreateCurrentMF() {
+	p.currentIsSummaryCount = false
+	p.currentIsSummarySum = false
+	p.currentIsHistogramCount = false
+	p.currentIsHistogramSum = false
+	name := p.currentToken.String()
+	if p.currentMF = p.metricFamiliesByName[name]; p.currentMF != nil {
+		return
+	}
+	// Try out if this is a _sum or _count for a summary/histogram.
+	summaryName := summaryMetricName(name)
+	if p.currentMF = p.metricFamiliesByName[summaryName]; p.currentMF != nil {
+		if p.currentMF.GetType() == dto.MetricType_SUMMARY {
+			if isCount(name) {
+				p.currentIsSummaryCount = true
+			}
+			if isSum(name) {
+				p.currentIsSummarySum = true
+			}
+			return
+		}
+	}
+	histogramName := histogramMetricName(name)
+	if p.currentMF = p.metricFamiliesByName[histogramName]; p.currentMF != nil {
+		if p.currentMF.GetType() == dto.MetricType_HISTOGRAM {
+			if isCount(name) {
+				p.currentIsHistogramCount = true
+			}
+			if isSum(name) {
+				p.currentIsHistogramSum = true
+			}
+			return
+		}
+	}
+	p.currentMF = &dto.MetricFamily{Name: proto.String(name)}
+	p.metricFamiliesByName[name] = p.currentMF
+}
+
+func isValidLabelNameStart(b byte) bool {
+	return (b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_'
+}
+
+func isValidLabelNameContinuation(b byte) bool {
+	return isValidLabelNameStart(b) || (b >= '0' && b <= '9')
+}
+
+func isValidMetricNameStart(b byte) bool {
+	return isValidLabelNameStart(b) || b == ':'
+}
+
+func isValidMetricNameContinuation(b byte) bool {
+	return isValidLabelNameContinuation(b) || b == ':'
+}
+
+func isBlankOrTab(b byte) bool {
+	return b == ' ' || b == '\t'
+}
+
+func isCount(name string) bool {
+	return len(name) > 6 && name[len(name)-6:] == "_count"
+}
+
+func isSum(name string) bool {
+	return len(name) > 4 && name[len(name)-4:] == "_sum"
+}
+
+func isBucket(name string) bool {
+	return len(name) > 7 && name[len(name)-7:] == "_bucket"
+}
+
+func summaryMetricName(name string) string {
+	switch {
+	case isCount(name):
+		return name[:len(name)-6]
+	case isSum(name):
+		return name[:len(name)-4]
+	default:
+		return name
+	}
+}
+
+func histogramMetricName(name string) string {
+	switch {
+	case isCount(name):
+		return name[:len(name)-6]
+	case isSum(name):
+		return name[:len(name)-4]
+	case isBucket(name):
+		return name[:len(name)-7]
+	default:
+		return name
+	}
+}

vendor/github.com/prometheus/common/internal/bitbucket.org/ww/goautoneg/autoneg.go

@@ -0,0 +1,162 @@
+/*
+HTTP Content-Type Autonegotiation.
+
+The functions in this package implement the behaviour specified in
+http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html
+
+Copyright (c) 2011, Open Knowledge Foundation Ltd.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+
+    Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+
+    Neither the name of the Open Knowledge Foundation Ltd. nor the
+    names of its contributors may be used to endorse or promote
+    products derived from this software without specific prior written
+    permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+
+*/
+package goautoneg
+
+import (
+	"sort"
+	"strconv"
+	"strings"
+)
+
+// Structure to represent a clause in an HTTP Accept Header
+type Accept struct {
+	Type, SubType string
+	Q             float64
+	Params        map[string]string
+}
+
+// For internal use, so that we can use the sort interface
+type accept_slice []Accept
+
+func (accept accept_slice) Len() int {
+	slice := []Accept(accept)
+	return len(slice)
+}
+
+func (accept accept_slice) Less(i, j int) bool {
+	slice := []Accept(accept)
+	ai, aj := slice[i], slice[j]
+	if ai.Q > aj.Q {
+		return true
+	}
+	if ai.Type != "*" && aj.Type == "*" {
+		return true
+	}
+	if ai.SubType != "*" && aj.SubType == "*" {
+		return true
+	}
+	return false
+}
+
+func (accept accept_slice) Swap(i, j int) {
+	slice := []Accept(accept)
+	slice[i], slice[j] = slice[j], slice[i]
+}
+
+// Parse an Accept Header string returning a sorted list
+// of clauses
+func ParseAccept(header string) (accept []Accept) {
+	parts := strings.Split(header, ",")
+	accept = make([]Accept, 0, len(parts))
+	for _, part := range parts {
+		part := strings.Trim(part, " ")
+
+		a := Accept{}
+		a.Params = make(map[string]string)
+		a.Q = 1.0
+
+		mrp := strings.Split(part, ";")
+
+		media_range := mrp[0]
+		sp := strings.Split(media_range, "/")
+		a.Type = strings.Trim(sp[0], " ")
+
+		switch {
+		case len(sp) == 1 && a.Type == "*":
+			a.SubType = "*"
+		case len(sp) == 2:
+			a.SubType = strings.Trim(sp[1], " ")
+		default:
+			continue
+		}
+
+		if len(mrp) == 1 {
+			accept = append(accept, a)
+			continue
+		}
+
+		for _, param := range mrp[1:] {
+			sp := strings.SplitN(param, "=", 2)
+			if len(sp) != 2 {
+				continue
+			}
+			token := strings.Trim(sp[0], " ")
+			if token == "q" {
+				a.Q, _ = strconv.ParseFloat(sp[1], 32)
+			} else {
+				a.Params[token] = strings.Trim(sp[1], " ")
+			}
+		}
+
+		accept = append(accept, a)
+	}
+
+	slice := accept_slice(accept)
+	sort.Sort(slice)
+
+	return
+}
+
+// Negotiate the most appropriate content_type given the accept header
+// and a list of alternatives.
+func Negotiate(header string, alternatives []string) (content_type string) {
+	asp := make([][]string, 0, len(alternatives))
+	for _, ctype := range alternatives {
+		asp = append(asp, strings.SplitN(ctype, "/", 2))
+	}
+	for _, clause := range ParseAccept(header) {
+		for i, ctsp := range asp {
+			if clause.Type == ctsp[0] && clause.SubType == ctsp[1] {
+				content_type = alternatives[i]
+				return
+			}
+			if clause.Type == ctsp[0] && clause.SubType == "*" {
+				content_type = alternatives[i]
+				return
+			}
+			if clause.Type == "*" && clause.SubType == "*" {
+				content_type = alternatives[i]
+				return
+			}
+		}
+	}
+	return
+}

vendor/github.com/prometheus/common/model/alert.go

@@ -0,0 +1,136 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"fmt"
+	"time"
+)
+
+type AlertStatus string
+
+const (
+	AlertFiring   AlertStatus = "firing"
+	AlertResolved AlertStatus = "resolved"
+)
+
+// Alert is a generic representation of an alert in the Prometheus eco-system.
+type Alert struct {
+	// Label value pairs for purpose of aggregation, matching, and disposition
+	// dispatching. This must minimally include an "alertname" label.
+	Labels LabelSet `json:"labels"`
+
+	// Extra key/value information which does not define alert identity.
+	Annotations LabelSet `json:"annotations"`
+
+	// The known time range for this alert. Both ends are optional.
+	StartsAt     time.Time `json:"startsAt,omitempty"`
+	EndsAt       time.Time `json:"endsAt,omitempty"`
+	GeneratorURL string    `json:"generatorURL"`
+}
+
+// Name returns the name of the alert. It is equivalent to the "alertname" label.
+func (a *Alert) Name() string {
+	return string(a.Labels[AlertNameLabel])
+}
+
+// Fingerprint returns a unique hash for the alert. It is equivalent to
+// the fingerprint of the alert's label set.
+func (a *Alert) Fingerprint() Fingerprint {
+	return a.Labels.Fingerprint()
+}
+
+func (a *Alert) String() string {
+	s := fmt.Sprintf("%s[%s]", a.Name(), a.Fingerprint().String()[:7])
+	if a.Resolved() {
+		return s + "[resolved]"
+	}
+	return s + "[active]"
+}
+
+// Resolved returns true iff the activity interval ended in the past.
+func (a *Alert) Resolved() bool {
+	return a.ResolvedAt(time.Now())
+}
+
+// ResolvedAt returns true off the activity interval ended before
+// the given timestamp.
+func (a *Alert) ResolvedAt(ts time.Time) bool {
+	if a.EndsAt.IsZero() {
+		return false
+	}
+	return !a.EndsAt.After(ts)
+}
+
+// Status returns the status of the alert.
+func (a *Alert) Status() AlertStatus {
+	if a.Resolved() {
+		return AlertResolved
+	}
+	return AlertFiring
+}
+
+// Validate checks whether the alert data is inconsistent.
+func (a *Alert) Validate() error {
+	if a.StartsAt.IsZero() {
+		return fmt.Errorf("start time missing")
+	}
+	if !a.EndsAt.IsZero() && a.EndsAt.Before(a.StartsAt) {
+		return fmt.Errorf("start time must be before end time")
+	}
+	if err := a.Labels.Validate(); err != nil {
+		return fmt.Errorf("invalid label set: %s", err)
+	}
+	if len(a.Labels) == 0 {
+		return fmt.Errorf("at least one label pair required")
+	}
+	if err := a.Annotations.Validate(); err != nil {
+		return fmt.Errorf("invalid annotations: %s", err)
+	}
+	return nil
+}
+
+// Alert is a list of alerts that can be sorted in chronological order.
+type Alerts []*Alert
+
+func (as Alerts) Len() int      { return len(as) }
+func (as Alerts) Swap(i, j int) { as[i], as[j] = as[j], as[i] }
+
+func (as Alerts) Less(i, j int) bool {
+	if as[i].StartsAt.Before(as[j].StartsAt) {
+		return true
+	}
+	if as[i].EndsAt.Before(as[j].EndsAt) {
+		return true
+	}
+	return as[i].Fingerprint() < as[j].Fingerprint()
+}
+
+// HasFiring returns true iff one of the alerts is not resolved.
+func (as Alerts) HasFiring() bool {
+	for _, a := range as {
+		if !a.Resolved() {
+			return true
+		}
+	}
+	return false
+}
+
+// Status returns StatusFiring iff at least one of the alerts is firing.
+func (as Alerts) Status() AlertStatus {
+	if as.HasFiring() {
+		return AlertFiring
+	}
+	return AlertResolved
+}

vendor/github.com/prometheus/common/model/fingerprinting.go

@@ -0,0 +1,105 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"fmt"
+	"strconv"
+)
+
+// Fingerprint provides a hash-capable representation of a Metric.
+// For our purposes, FNV-1A 64-bit is used.
+type Fingerprint uint64
+
+// FingerprintFromString transforms a string representation into a Fingerprint.
+func FingerprintFromString(s string) (Fingerprint, error) {
+	num, err := strconv.ParseUint(s, 16, 64)
+	return Fingerprint(num), err
+}
+
+// ParseFingerprint parses the input string into a fingerprint.
+func ParseFingerprint(s string) (Fingerprint, error) {
+	num, err := strconv.ParseUint(s, 16, 64)
+	if err != nil {
+		return 0, err
+	}
+	return Fingerprint(num), nil
+}
+
+func (f Fingerprint) String() string {
+	return fmt.Sprintf("%016x", uint64(f))
+}
+
+// Fingerprints represents a collection of Fingerprint subject to a given
+// natural sorting scheme. It implements sort.Interface.
+type Fingerprints []Fingerprint
+
+// Len implements sort.Interface.
+func (f Fingerprints) Len() int {
+	return len(f)
+}
+
+// Less implements sort.Interface.
+func (f Fingerprints) Less(i, j int) bool {
+	return f[i] < f[j]
+}
+
+// Swap implements sort.Interface.
+func (f Fingerprints) Swap(i, j int) {
+	f[i], f[j] = f[j], f[i]
+}
+
+// FingerprintSet is a set of Fingerprints.
+type FingerprintSet map[Fingerprint]struct{}
+
+// Equal returns true if both sets contain the same elements (and not more).
+func (s FingerprintSet) Equal(o FingerprintSet) bool {
+	if len(s) != len(o) {
+		return false
+	}
+
+	for k := range s {
+		if _, ok := o[k]; !ok {
+			return false
+		}
+	}
+
+	return true
+}
+
+// Intersection returns the elements contained in both sets.
+func (s FingerprintSet) Intersection(o FingerprintSet) FingerprintSet {
+	myLength, otherLength := len(s), len(o)
+	if myLength == 0 || otherLength == 0 {
+		return FingerprintSet{}
+	}
+
+	subSet := s
+	superSet := o
+
+	if otherLength < myLength {
+		subSet = o
+		superSet = s
+	}
+
+	out := FingerprintSet{}
+
+	for k := range subSet {
+		if _, ok := superSet[k]; ok {
+			out[k] = struct{}{}
+		}
+	}
+
+	return out
+}

vendor/github.com/prometheus/common/model/fnv.go

@@ -0,0 +1,42 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+// Inline and byte-free variant of hash/fnv's fnv64a.
+
+const (
+	offset64 = 14695981039346656037
+	prime64  = 1099511628211
+)
+
+// hashNew initializies a new fnv64a hash value.
+func hashNew() uint64 {
+	return offset64
+}
+
+// hashAdd adds a string to a fnv64a hash value, returning the updated hash.
+func hashAdd(h uint64, s string) uint64 {
+	for i := 0; i < len(s); i++ {
+		h ^= uint64(s[i])
+		h *= prime64
+	}
+	return h
+}
+
+// hashAddByte adds a byte to a fnv64a hash value, returning the updated hash.
+func hashAddByte(h uint64, b byte) uint64 {
+	h ^= uint64(b)
+	h *= prime64
+	return h
+}

vendor/github.com/prometheus/common/model/labels.go

@@ -0,0 +1,210 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"encoding/json"
+	"fmt"
+	"regexp"
+	"strings"
+	"unicode/utf8"
+)
+
+const (
+	// AlertNameLabel is the name of the label containing the an alert's name.
+	AlertNameLabel = "alertname"
+
+	// ExportedLabelPrefix is the prefix to prepend to the label names present in
+	// exported metrics if a label of the same name is added by the server.
+	ExportedLabelPrefix = "exported_"
+
+	// MetricNameLabel is the label name indicating the metric name of a
+	// timeseries.
+	MetricNameLabel = "__name__"
+
+	// SchemeLabel is the name of the label that holds the scheme on which to
+	// scrape a target.
+	SchemeLabel = "__scheme__"
+
+	// AddressLabel is the name of the label that holds the address of
+	// a scrape target.
+	AddressLabel = "__address__"
+
+	// MetricsPathLabel is the name of the label that holds the path on which to
+	// scrape a target.
+	MetricsPathLabel = "__metrics_path__"
+
+	// ReservedLabelPrefix is a prefix which is not legal in user-supplied
+	// label names.
+	ReservedLabelPrefix = "__"
+
+	// MetaLabelPrefix is a prefix for labels that provide meta information.
+	// Labels with this prefix are used for intermediate label processing and
+	// will not be attached to time series.
+	MetaLabelPrefix = "__meta_"
+
+	// TmpLabelPrefix is a prefix for temporary labels as part of relabelling.
+	// Labels with this prefix are used for intermediate label processing and
+	// will not be attached to time series. This is reserved for use in
+	// Prometheus configuration files by users.
+	TmpLabelPrefix = "__tmp_"
+
+	// ParamLabelPrefix is a prefix for labels that provide URL parameters
+	// used to scrape a target.
+	ParamLabelPrefix = "__param_"
+
+	// JobLabel is the label name indicating the job from which a timeseries
+	// was scraped.
+	JobLabel = "job"
+
+	// InstanceLabel is the label name used for the instance label.
+	InstanceLabel = "instance"
+
+	// BucketLabel is used for the label that defines the upper bound of a
+	// bucket of a histogram ("le" -> "less or equal").
+	BucketLabel = "le"
+
+	// QuantileLabel is used for the label that defines the quantile in a
+	// summary.
+	QuantileLabel = "quantile"
+)
+
+// LabelNameRE is a regular expression matching valid label names. Note that the
+// IsValid method of LabelName performs the same check but faster than a match
+// with this regular expression.
+var LabelNameRE = regexp.MustCompile("^[a-zA-Z_][a-zA-Z0-9_]*$")
+
+// A LabelName is a key for a LabelSet or Metric.  It has a value associated
+// therewith.
+type LabelName string
+
+// IsValid is true iff the label name matches the pattern of LabelNameRE. This
+// method, however, does not use LabelNameRE for the check but a much faster
+// hardcoded implementation.
+func (ln LabelName) IsValid() bool {
+	if len(ln) == 0 {
+		return false
+	}
+	for i, b := range ln {
+		if !((b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_' || (b >= '0' && b <= '9' && i > 0)) {
+			return false
+		}
+	}
+	return true
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (ln *LabelName) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var s string
+	if err := unmarshal(&s); err != nil {
+		return err
+	}
+	if !LabelName(s).IsValid() {
+		return fmt.Errorf("%q is not a valid label name", s)
+	}
+	*ln = LabelName(s)
+	return nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (ln *LabelName) UnmarshalJSON(b []byte) error {
+	var s string
+	if err := json.Unmarshal(b, &s); err != nil {
+		return err
+	}
+	if !LabelName(s).IsValid() {
+		return fmt.Errorf("%q is not a valid label name", s)
+	}
+	*ln = LabelName(s)
+	return nil
+}
+
+// LabelNames is a sortable LabelName slice. In implements sort.Interface.
+type LabelNames []LabelName
+
+func (l LabelNames) Len() int {
+	return len(l)
+}
+
+func (l LabelNames) Less(i, j int) bool {
+	return l[i] < l[j]
+}
+
+func (l LabelNames) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}
+
+func (l LabelNames) String() string {
+	labelStrings := make([]string, 0, len(l))
+	for _, label := range l {
+		labelStrings = append(labelStrings, string(label))
+	}
+	return strings.Join(labelStrings, ", ")
+}
+
+// A LabelValue is an associated value for a LabelName.
+type LabelValue string
+
+// IsValid returns true iff the string is a valid UTF8.
+func (lv LabelValue) IsValid() bool {
+	return utf8.ValidString(string(lv))
+}
+
+// LabelValues is a sortable LabelValue slice. It implements sort.Interface.
+type LabelValues []LabelValue
+
+func (l LabelValues) Len() int {
+	return len(l)
+}
+
+func (l LabelValues) Less(i, j int) bool {
+	return string(l[i]) < string(l[j])
+}
+
+func (l LabelValues) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}
+
+// LabelPair pairs a name with a value.
+type LabelPair struct {
+	Name  LabelName
+	Value LabelValue
+}
+
+// LabelPairs is a sortable slice of LabelPair pointers. It implements
+// sort.Interface.
+type LabelPairs []*LabelPair
+
+func (l LabelPairs) Len() int {
+	return len(l)
+}
+
+func (l LabelPairs) Less(i, j int) bool {
+	switch {
+	case l[i].Name > l[j].Name:
+		return false
+	case l[i].Name < l[j].Name:
+		return true
+	case l[i].Value > l[j].Value:
+		return false
+	case l[i].Value < l[j].Value:
+		return true
+	default:
+		return false
+	}
+}
+
+func (l LabelPairs) Swap(i, j int) {
+	l[i], l[j] = l[j], l[i]
+}

vendor/github.com/prometheus/common/model/labelset.go

@@ -0,0 +1,169 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"encoding/json"
+	"fmt"
+	"sort"
+	"strings"
+)
+
+// A LabelSet is a collection of LabelName and LabelValue pairs.  The LabelSet
+// may be fully-qualified down to the point where it may resolve to a single
+// Metric in the data store or not.  All operations that occur within the realm
+// of a LabelSet can emit a vector of Metric entities to which the LabelSet may
+// match.
+type LabelSet map[LabelName]LabelValue
+
+// Validate checks whether all names and values in the label set
+// are valid.
+func (ls LabelSet) Validate() error {
+	for ln, lv := range ls {
+		if !ln.IsValid() {
+			return fmt.Errorf("invalid name %q", ln)
+		}
+		if !lv.IsValid() {
+			return fmt.Errorf("invalid value %q", lv)
+		}
+	}
+	return nil
+}
+
+// Equal returns true iff both label sets have exactly the same key/value pairs.
+func (ls LabelSet) Equal(o LabelSet) bool {
+	if len(ls) != len(o) {
+		return false
+	}
+	for ln, lv := range ls {
+		olv, ok := o[ln]
+		if !ok {
+			return false
+		}
+		if olv != lv {
+			return false
+		}
+	}
+	return true
+}
+
+// Before compares the metrics, using the following criteria:
+//
+// If m has fewer labels than o, it is before o. If it has more, it is not.
+//
+// If the number of labels is the same, the superset of all label names is
+// sorted alphanumerically. The first differing label pair found in that order
+// determines the outcome: If the label does not exist at all in m, then m is
+// before o, and vice versa. Otherwise the label value is compared
+// alphanumerically.
+//
+// If m and o are equal, the method returns false.
+func (ls LabelSet) Before(o LabelSet) bool {
+	if len(ls) < len(o) {
+		return true
+	}
+	if len(ls) > len(o) {
+		return false
+	}
+
+	lns := make(LabelNames, 0, len(ls)+len(o))
+	for ln := range ls {
+		lns = append(lns, ln)
+	}
+	for ln := range o {
+		lns = append(lns, ln)
+	}
+	// It's probably not worth it to de-dup lns.
+	sort.Sort(lns)
+	for _, ln := range lns {
+		mlv, ok := ls[ln]
+		if !ok {
+			return true
+		}
+		olv, ok := o[ln]
+		if !ok {
+			return false
+		}
+		if mlv < olv {
+			return true
+		}
+		if mlv > olv {
+			return false
+		}
+	}
+	return false
+}
+
+// Clone returns a copy of the label set.
+func (ls LabelSet) Clone() LabelSet {
+	lsn := make(LabelSet, len(ls))
+	for ln, lv := range ls {
+		lsn[ln] = lv
+	}
+	return lsn
+}
+
+// Merge is a helper function to non-destructively merge two label sets.
+func (l LabelSet) Merge(other LabelSet) LabelSet {
+	result := make(LabelSet, len(l))
+
+	for k, v := range l {
+		result[k] = v
+	}
+
+	for k, v := range other {
+		result[k] = v
+	}
+
+	return result
+}
+
+func (l LabelSet) String() string {
+	lstrs := make([]string, 0, len(l))
+	for l, v := range l {
+		lstrs = append(lstrs, fmt.Sprintf("%s=%q", l, v))
+	}
+
+	sort.Strings(lstrs)
+	return fmt.Sprintf("{%s}", strings.Join(lstrs, ", "))
+}
+
+// Fingerprint returns the LabelSet's fingerprint.
+func (ls LabelSet) Fingerprint() Fingerprint {
+	return labelSetToFingerprint(ls)
+}
+
+// FastFingerprint returns the LabelSet's Fingerprint calculated by a faster hashing
+// algorithm, which is, however, more susceptible to hash collisions.
+func (ls LabelSet) FastFingerprint() Fingerprint {
+	return labelSetToFastFingerprint(ls)
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (l *LabelSet) UnmarshalJSON(b []byte) error {
+	var m map[LabelName]LabelValue
+	if err := json.Unmarshal(b, &m); err != nil {
+		return err
+	}
+	// encoding/json only unmarshals maps of the form map[string]T. It treats
+	// LabelName as a string and does not call its UnmarshalJSON method.
+	// Thus, we have to replicate the behavior here.
+	for ln := range m {
+		if !ln.IsValid() {
+			return fmt.Errorf("%q is not a valid label name", ln)
+		}
+	}
+	*l = LabelSet(m)
+	return nil
+}

vendor/github.com/prometheus/common/model/metric.go

@@ -0,0 +1,103 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"fmt"
+	"regexp"
+	"sort"
+	"strings"
+)
+
+var (
+	separator = []byte{0}
+	// MetricNameRE is a regular expression matching valid metric
+	// names. Note that the IsValidMetricName function performs the same
+	// check but faster than a match with this regular expression.
+	MetricNameRE = regexp.MustCompile(`^[a-zA-Z_:][a-zA-Z0-9_:]*$`)
+)
+
+// A Metric is similar to a LabelSet, but the key difference is that a Metric is
+// a singleton and refers to one and only one stream of samples.
+type Metric LabelSet
+
+// Equal compares the metrics.
+func (m Metric) Equal(o Metric) bool {
+	return LabelSet(m).Equal(LabelSet(o))
+}
+
+// Before compares the metrics' underlying label sets.
+func (m Metric) Before(o Metric) bool {
+	return LabelSet(m).Before(LabelSet(o))
+}
+
+// Clone returns a copy of the Metric.
+func (m Metric) Clone() Metric {
+	clone := make(Metric, len(m))
+	for k, v := range m {
+		clone[k] = v
+	}
+	return clone
+}
+
+func (m Metric) String() string {
+	metricName, hasName := m[MetricNameLabel]
+	numLabels := len(m) - 1
+	if !hasName {
+		numLabels = len(m)
+	}
+	labelStrings := make([]string, 0, numLabels)
+	for label, value := range m {
+		if label != MetricNameLabel {
+			labelStrings = append(labelStrings, fmt.Sprintf("%s=%q", label, value))
+		}
+	}
+
+	switch numLabels {
+	case 0:
+		if hasName {
+			return string(metricName)
+		}
+		return "{}"
+	default:
+		sort.Strings(labelStrings)
+		return fmt.Sprintf("%s{%s}", metricName, strings.Join(labelStrings, ", "))
+	}
+}
+
+// Fingerprint returns a Metric's Fingerprint.
+func (m Metric) Fingerprint() Fingerprint {
+	return LabelSet(m).Fingerprint()
+}
+
+// FastFingerprint returns a Metric's Fingerprint calculated by a faster hashing
+// algorithm, which is, however, more susceptible to hash collisions.
+func (m Metric) FastFingerprint() Fingerprint {
+	return LabelSet(m).FastFingerprint()
+}
+
+// IsValidMetricName returns true iff name matches the pattern of MetricNameRE.
+// This function, however, does not use MetricNameRE for the check but a much
+// faster hardcoded implementation.
+func IsValidMetricName(n LabelValue) bool {
+	if len(n) == 0 {
+		return false
+	}
+	for i, b := range n {
+		if !((b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_' || b == ':' || (b >= '0' && b <= '9' && i > 0)) {
+			return false
+		}
+	}
+	return true
+}

vendor/github.com/prometheus/common/model/model.go

@@ -0,0 +1,16 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package model contains common data structures that are shared across
+// Prometheus components and libraries.
+package model

vendor/github.com/prometheus/common/model/signature.go

@@ -0,0 +1,144 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"sort"
+)
+
+// SeparatorByte is a byte that cannot occur in valid UTF-8 sequences and is
+// used to separate label names, label values, and other strings from each other
+// when calculating their combined hash value (aka signature aka fingerprint).
+const SeparatorByte byte = 255
+
+var (
+	// cache the signature of an empty label set.
+	emptyLabelSignature = hashNew()
+)
+
+// LabelsToSignature returns a quasi-unique signature (i.e., fingerprint) for a
+// given label set. (Collisions are possible but unlikely if the number of label
+// sets the function is applied to is small.)
+func LabelsToSignature(labels map[string]string) uint64 {
+	if len(labels) == 0 {
+		return emptyLabelSignature
+	}
+
+	labelNames := make([]string, 0, len(labels))
+	for labelName := range labels {
+		labelNames = append(labelNames, labelName)
+	}
+	sort.Strings(labelNames)
+
+	sum := hashNew()
+	for _, labelName := range labelNames {
+		sum = hashAdd(sum, labelName)
+		sum = hashAddByte(sum, SeparatorByte)
+		sum = hashAdd(sum, labels[labelName])
+		sum = hashAddByte(sum, SeparatorByte)
+	}
+	return sum
+}
+
+// labelSetToFingerprint works exactly as LabelsToSignature but takes a LabelSet as
+// parameter (rather than a label map) and returns a Fingerprint.
+func labelSetToFingerprint(ls LabelSet) Fingerprint {
+	if len(ls) == 0 {
+		return Fingerprint(emptyLabelSignature)
+	}
+
+	labelNames := make(LabelNames, 0, len(ls))
+	for labelName := range ls {
+		labelNames = append(labelNames, labelName)
+	}
+	sort.Sort(labelNames)
+
+	sum := hashNew()
+	for _, labelName := range labelNames {
+		sum = hashAdd(sum, string(labelName))
+		sum = hashAddByte(sum, SeparatorByte)
+		sum = hashAdd(sum, string(ls[labelName]))
+		sum = hashAddByte(sum, SeparatorByte)
+	}
+	return Fingerprint(sum)
+}
+
+// labelSetToFastFingerprint works similar to labelSetToFingerprint but uses a
+// faster and less allocation-heavy hash function, which is more susceptible to
+// create hash collisions. Therefore, collision detection should be applied.
+func labelSetToFastFingerprint(ls LabelSet) Fingerprint {
+	if len(ls) == 0 {
+		return Fingerprint(emptyLabelSignature)
+	}
+
+	var result uint64
+	for labelName, labelValue := range ls {
+		sum := hashNew()
+		sum = hashAdd(sum, string(labelName))
+		sum = hashAddByte(sum, SeparatorByte)
+		sum = hashAdd(sum, string(labelValue))
+		result ^= sum
+	}
+	return Fingerprint(result)
+}
+
+// SignatureForLabels works like LabelsToSignature but takes a Metric as
+// parameter (rather than a label map) and only includes the labels with the
+// specified LabelNames into the signature calculation. The labels passed in
+// will be sorted by this function.
+func SignatureForLabels(m Metric, labels ...LabelName) uint64 {
+	if len(labels) == 0 {
+		return emptyLabelSignature
+	}
+
+	sort.Sort(LabelNames(labels))
+
+	sum := hashNew()
+	for _, label := range labels {
+		sum = hashAdd(sum, string(label))
+		sum = hashAddByte(sum, SeparatorByte)
+		sum = hashAdd(sum, string(m[label]))
+		sum = hashAddByte(sum, SeparatorByte)
+	}
+	return sum
+}
+
+// SignatureWithoutLabels works like LabelsToSignature but takes a Metric as
+// parameter (rather than a label map) and excludes the labels with any of the
+// specified LabelNames from the signature calculation.
+func SignatureWithoutLabels(m Metric, labels map[LabelName]struct{}) uint64 {
+	if len(m) == 0 {
+		return emptyLabelSignature
+	}
+
+	labelNames := make(LabelNames, 0, len(m))
+	for labelName := range m {
+		if _, exclude := labels[labelName]; !exclude {
+			labelNames = append(labelNames, labelName)
+		}
+	}
+	if len(labelNames) == 0 {
+		return emptyLabelSignature
+	}
+	sort.Sort(labelNames)
+
+	sum := hashNew()
+	for _, labelName := range labelNames {
+		sum = hashAdd(sum, string(labelName))
+		sum = hashAddByte(sum, SeparatorByte)
+		sum = hashAdd(sum, string(m[labelName]))
+		sum = hashAddByte(sum, SeparatorByte)
+	}
+	return sum
+}

vendor/github.com/prometheus/common/model/silence.go

@@ -0,0 +1,106 @@
+// Copyright 2015 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"encoding/json"
+	"fmt"
+	"regexp"
+	"time"
+)
+
+// Matcher describes a matches the value of a given label.
+type Matcher struct {
+	Name    LabelName `json:"name"`
+	Value   string    `json:"value"`
+	IsRegex bool      `json:"isRegex"`
+}
+
+func (m *Matcher) UnmarshalJSON(b []byte) error {
+	type plain Matcher
+	if err := json.Unmarshal(b, (*plain)(m)); err != nil {
+		return err
+	}
+
+	if len(m.Name) == 0 {
+		return fmt.Errorf("label name in matcher must not be empty")
+	}
+	if m.IsRegex {
+		if _, err := regexp.Compile(m.Value); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// Validate returns true iff all fields of the matcher have valid values.
+func (m *Matcher) Validate() error {
+	if !m.Name.IsValid() {
+		return fmt.Errorf("invalid name %q", m.Name)
+	}
+	if m.IsRegex {
+		if _, err := regexp.Compile(m.Value); err != nil {
+			return fmt.Errorf("invalid regular expression %q", m.Value)
+		}
+	} else if !LabelValue(m.Value).IsValid() || len(m.Value) == 0 {
+		return fmt.Errorf("invalid value %q", m.Value)
+	}
+	return nil
+}
+
+// Silence defines the representation of a silence definition in the Prometheus
+// eco-system.
+type Silence struct {
+	ID uint64 `json:"id,omitempty"`
+
+	Matchers []*Matcher `json:"matchers"`
+
+	StartsAt time.Time `json:"startsAt"`
+	EndsAt   time.Time `json:"endsAt"`
+
+	CreatedAt time.Time `json:"createdAt,omitempty"`
+	CreatedBy string    `json:"createdBy"`
+	Comment   string    `json:"comment,omitempty"`
+}
+
+// Validate returns true iff all fields of the silence have valid values.
+func (s *Silence) Validate() error {
+	if len(s.Matchers) == 0 {
+		return fmt.Errorf("at least one matcher required")
+	}
+	for _, m := range s.Matchers {
+		if err := m.Validate(); err != nil {
+			return fmt.Errorf("invalid matcher: %s", err)
+		}
+	}
+	if s.StartsAt.IsZero() {
+		return fmt.Errorf("start time missing")
+	}
+	if s.EndsAt.IsZero() {
+		return fmt.Errorf("end time missing")
+	}
+	if s.EndsAt.Before(s.StartsAt) {
+		return fmt.Errorf("start time must be before end time")
+	}
+	if s.CreatedBy == "" {
+		return fmt.Errorf("creator information missing")
+	}
+	if s.Comment == "" {
+		return fmt.Errorf("comment missing")
+	}
+	if s.CreatedAt.IsZero() {
+		return fmt.Errorf("creation timestamp missing")
+	}
+	return nil
+}

vendor/github.com/prometheus/common/model/time.go

@@ -0,0 +1,264 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"fmt"
+	"math"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+)
+
+const (
+	// MinimumTick is the minimum supported time resolution. This has to be
+	// at least time.Second in order for the code below to work.
+	minimumTick = time.Millisecond
+	// second is the Time duration equivalent to one second.
+	second = int64(time.Second / minimumTick)
+	// The number of nanoseconds per minimum tick.
+	nanosPerTick = int64(minimumTick / time.Nanosecond)
+
+	// Earliest is the earliest Time representable. Handy for
+	// initializing a high watermark.
+	Earliest = Time(math.MinInt64)
+	// Latest is the latest Time representable. Handy for initializing
+	// a low watermark.
+	Latest = Time(math.MaxInt64)
+)
+
+// Time is the number of milliseconds since the epoch
+// (1970-01-01 00:00 UTC) excluding leap seconds.
+type Time int64
+
+// Interval describes and interval between two timestamps.
+type Interval struct {
+	Start, End Time
+}
+
+// Now returns the current time as a Time.
+func Now() Time {
+	return TimeFromUnixNano(time.Now().UnixNano())
+}
+
+// TimeFromUnix returns the Time equivalent to the Unix Time t
+// provided in seconds.
+func TimeFromUnix(t int64) Time {
+	return Time(t * second)
+}
+
+// TimeFromUnixNano returns the Time equivalent to the Unix Time
+// t provided in nanoseconds.
+func TimeFromUnixNano(t int64) Time {
+	return Time(t / nanosPerTick)
+}
+
+// Equal reports whether two Times represent the same instant.
+func (t Time) Equal(o Time) bool {
+	return t == o
+}
+
+// Before reports whether the Time t is before o.
+func (t Time) Before(o Time) bool {
+	return t < o
+}
+
+// After reports whether the Time t is after o.
+func (t Time) After(o Time) bool {
+	return t > o
+}
+
+// Add returns the Time t + d.
+func (t Time) Add(d time.Duration) Time {
+	return t + Time(d/minimumTick)
+}
+
+// Sub returns the Duration t - o.
+func (t Time) Sub(o Time) time.Duration {
+	return time.Duration(t-o) * minimumTick
+}
+
+// Time returns the time.Time representation of t.
+func (t Time) Time() time.Time {
+	return time.Unix(int64(t)/second, (int64(t)%second)*nanosPerTick)
+}
+
+// Unix returns t as a Unix time, the number of seconds elapsed
+// since January 1, 1970 UTC.
+func (t Time) Unix() int64 {
+	return int64(t) / second
+}
+
+// UnixNano returns t as a Unix time, the number of nanoseconds elapsed
+// since January 1, 1970 UTC.
+func (t Time) UnixNano() int64 {
+	return int64(t) * nanosPerTick
+}
+
+// The number of digits after the dot.
+var dotPrecision = int(math.Log10(float64(second)))
+
+// String returns a string representation of the Time.
+func (t Time) String() string {
+	return strconv.FormatFloat(float64(t)/float64(second), 'f', -1, 64)
+}
+
+// MarshalJSON implements the json.Marshaler interface.
+func (t Time) MarshalJSON() ([]byte, error) {
+	return []byte(t.String()), nil
+}
+
+// UnmarshalJSON implements the json.Unmarshaler interface.
+func (t *Time) UnmarshalJSON(b []byte) error {
+	p := strings.Split(string(b), ".")
+	switch len(p) {
+	case 1:
+		v, err := strconv.ParseInt(string(p[0]), 10, 64)
+		if err != nil {
+			return err
+		}
+		*t = Time(v * second)
+
+	case 2:
+		v, err := strconv.ParseInt(string(p[0]), 10, 64)
+		if err != nil {
+			return err
+		}
+		v *= second
+
+		prec := dotPrecision - len(p[1])
+		if prec < 0 {
+			p[1] = p[1][:dotPrecision]
+		} else if prec > 0 {
+			p[1] = p[1] + strings.Repeat("0", prec)
+		}
+
+		va, err := strconv.ParseInt(p[1], 10, 32)
+		if err != nil {
+			return err
+		}
+
+		*t = Time(v + va)
+
+	default:
+		return fmt.Errorf("invalid time %q", string(b))
+	}
+	return nil
+}
+
+// Duration wraps time.Duration. It is used to parse the custom duration format
+// from YAML.
+// This type should not propagate beyond the scope of input/output processing.
+type Duration time.Duration
+
+// Set implements pflag/flag.Value
+func (d *Duration) Set(s string) error {
+	var err error
+	*d, err = ParseDuration(s)
+	return err
+}
+
+// Type implements pflag.Value
+func (d *Duration) Type() string {
+	return "duration"
+}
+
+var durationRE = regexp.MustCompile("^([0-9]+)(y|w|d|h|m|s|ms)$")
+
+// ParseDuration parses a string into a time.Duration, assuming that a year
+// always has 365d, a week always has 7d, and a day always has 24h.
+func ParseDuration(durationStr string) (Duration, error) {
+	matches := durationRE.FindStringSubmatch(durationStr)
+	if len(matches) != 3 {
+		return 0, fmt.Errorf("not a valid duration string: %q", durationStr)
+	}
+	var (
+		n, _ = strconv.Atoi(matches[1])
+		dur  = time.Duration(n) * time.Millisecond
+	)
+	switch unit := matches[2]; unit {
+	case "y":
+		dur *= 1000 * 60 * 60 * 24 * 365
+	case "w":
+		dur *= 1000 * 60 * 60 * 24 * 7
+	case "d":
+		dur *= 1000 * 60 * 60 * 24
+	case "h":
+		dur *= 1000 * 60 * 60
+	case "m":
+		dur *= 1000 * 60
+	case "s":
+		dur *= 1000
+	case "ms":
+		// Value already correct
+	default:
+		return 0, fmt.Errorf("invalid time unit in duration string: %q", unit)
+	}
+	return Duration(dur), nil
+}
+
+func (d Duration) String() string {
+	var (
+		ms   = int64(time.Duration(d) / time.Millisecond)
+		unit = "ms"
+	)
+	if ms == 0 {
+		return "0s"
+	}
+	factors := map[string]int64{
+		"y":  1000 * 60 * 60 * 24 * 365,
+		"w":  1000 * 60 * 60 * 24 * 7,
+		"d":  1000 * 60 * 60 * 24,
+		"h":  1000 * 60 * 60,
+		"m":  1000 * 60,
+		"s":  1000,
+		"ms": 1,
+	}
+
+	switch int64(0) {
+	case ms % factors["y"]:
+		unit = "y"
+	case ms % factors["w"]:
+		unit = "w"
+	case ms % factors["d"]:
+		unit = "d"
+	case ms % factors["h"]:
+		unit = "h"
+	case ms % factors["m"]:
+		unit = "m"
+	case ms % factors["s"]:
+		unit = "s"
+	}
+	return fmt.Sprintf("%v%v", ms/factors[unit], unit)
+}
+
+// MarshalYAML implements the yaml.Marshaler interface.
+func (d Duration) MarshalYAML() (interface{}, error) {
+	return d.String(), nil
+}
+
+// UnmarshalYAML implements the yaml.Unmarshaler interface.
+func (d *Duration) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var s string
+	if err := unmarshal(&s); err != nil {
+		return err
+	}
+	dur, err := ParseDuration(s)
+	if err != nil {
+		return err
+	}
+	*d = dur
+	return nil
+}

vendor/github.com/prometheus/common/model/value.go

@@ -0,0 +1,416 @@
+// Copyright 2013 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package model
+
+import (
+	"encoding/json"
+	"fmt"
+	"math"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+var (
+	// ZeroSamplePair is the pseudo zero-value of SamplePair used to signal a
+	// non-existing sample pair. It is a SamplePair with timestamp Earliest and
+	// value 0.0. Note that the natural zero value of SamplePair has a timestamp
+	// of 0, which is possible to appear in a real SamplePair and thus not
+	// suitable to signal a non-existing SamplePair.
+	ZeroSamplePair = SamplePair{Timestamp: Earliest}
+
+	// ZeroSample is the pseudo zero-value of Sample used to signal a
+	// non-existing sample. It is a Sample with timestamp Earliest, value 0.0,
+	// and metric nil. Note that the natural zero value of Sample has a timestamp
+	// of 0, which is possible to appear in a real Sample and thus not suitable
+	// to signal a non-existing Sample.
+	ZeroSample = Sample{Timestamp: Earliest}
+)
+
+// A SampleValue is a representation of a value for a given sample at a given
+// time.
+type SampleValue float64
+
+// MarshalJSON implements json.Marshaler.
+func (v SampleValue) MarshalJSON() ([]byte, error) {
+	return json.Marshal(v.String())
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (v *SampleValue) UnmarshalJSON(b []byte) error {
+	if len(b) < 2 || b[0] != '"' || b[len(b)-1] != '"' {
+		return fmt.Errorf("sample value must be a quoted string")
+	}
+	f, err := strconv.ParseFloat(string(b[1:len(b)-1]), 64)
+	if err != nil {
+		return err
+	}
+	*v = SampleValue(f)
+	return nil
+}
+
+// Equal returns true if the value of v and o is equal or if both are NaN. Note
+// that v==o is false if both are NaN. If you want the conventional float
+// behavior, use == to compare two SampleValues.
+func (v SampleValue) Equal(o SampleValue) bool {
+	if v == o {
+		return true
+	}
+	return math.IsNaN(float64(v)) && math.IsNaN(float64(o))
+}
+
+func (v SampleValue) String() string {
+	return strconv.FormatFloat(float64(v), 'f', -1, 64)
+}
+
+// SamplePair pairs a SampleValue with a Timestamp.
+type SamplePair struct {
+	Timestamp Time
+	Value     SampleValue
+}
+
+// MarshalJSON implements json.Marshaler.
+func (s SamplePair) MarshalJSON() ([]byte, error) {
+	t, err := json.Marshal(s.Timestamp)
+	if err != nil {
+		return nil, err
+	}
+	v, err := json.Marshal(s.Value)
+	if err != nil {
+		return nil, err
+	}
+	return []byte(fmt.Sprintf("[%s,%s]", t, v)), nil
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *SamplePair) UnmarshalJSON(b []byte) error {
+	v := [...]json.Unmarshaler{&s.Timestamp, &s.Value}
+	return json.Unmarshal(b, &v)
+}
+
+// Equal returns true if this SamplePair and o have equal Values and equal
+// Timestamps. The semantics of Value equality is defined by SampleValue.Equal.
+func (s *SamplePair) Equal(o *SamplePair) bool {
+	return s == o || (s.Value.Equal(o.Value) && s.Timestamp.Equal(o.Timestamp))
+}
+
+func (s SamplePair) String() string {
+	return fmt.Sprintf("%s @[%s]", s.Value, s.Timestamp)
+}
+
+// Sample is a sample pair associated with a metric.
+type Sample struct {
+	Metric    Metric      `json:"metric"`
+	Value     SampleValue `json:"value"`
+	Timestamp Time        `json:"timestamp"`
+}
+
+// Equal compares first the metrics, then the timestamp, then the value. The
+// semantics of value equality is defined by SampleValue.Equal.
+func (s *Sample) Equal(o *Sample) bool {
+	if s == o {
+		return true
+	}
+
+	if !s.Metric.Equal(o.Metric) {
+		return false
+	}
+	if !s.Timestamp.Equal(o.Timestamp) {
+		return false
+	}
+
+	return s.Value.Equal(o.Value)
+}
+
+func (s Sample) String() string {
+	return fmt.Sprintf("%s => %s", s.Metric, SamplePair{
+		Timestamp: s.Timestamp,
+		Value:     s.Value,
+	})
+}
+
+// MarshalJSON implements json.Marshaler.
+func (s Sample) MarshalJSON() ([]byte, error) {
+	v := struct {
+		Metric Metric     `json:"metric"`
+		Value  SamplePair `json:"value"`
+	}{
+		Metric: s.Metric,
+		Value: SamplePair{
+			Timestamp: s.Timestamp,
+			Value:     s.Value,
+		},
+	}
+
+	return json.Marshal(&v)
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *Sample) UnmarshalJSON(b []byte) error {
+	v := struct {
+		Metric Metric     `json:"metric"`
+		Value  SamplePair `json:"value"`
+	}{
+		Metric: s.Metric,
+		Value: SamplePair{
+			Timestamp: s.Timestamp,
+			Value:     s.Value,
+		},
+	}
+
+	if err := json.Unmarshal(b, &v); err != nil {
+		return err
+	}
+
+	s.Metric = v.Metric
+	s.Timestamp = v.Value.Timestamp
+	s.Value = v.Value.Value
+
+	return nil
+}
+
+// Samples is a sortable Sample slice. It implements sort.Interface.
+type Samples []*Sample
+
+func (s Samples) Len() int {
+	return len(s)
+}
+
+// Less compares first the metrics, then the timestamp.
+func (s Samples) Less(i, j int) bool {
+	switch {
+	case s[i].Metric.Before(s[j].Metric):
+		return true
+	case s[j].Metric.Before(s[i].Metric):
+		return false
+	case s[i].Timestamp.Before(s[j].Timestamp):
+		return true
+	default:
+		return false
+	}
+}
+
+func (s Samples) Swap(i, j int) {
+	s[i], s[j] = s[j], s[i]
+}
+
+// Equal compares two sets of samples and returns true if they are equal.
+func (s Samples) Equal(o Samples) bool {
+	if len(s) != len(o) {
+		return false
+	}
+
+	for i, sample := range s {
+		if !sample.Equal(o[i]) {
+			return false
+		}
+	}
+	return true
+}
+
+// SampleStream is a stream of Values belonging to an attached COWMetric.
+type SampleStream struct {
+	Metric Metric       `json:"metric"`
+	Values []SamplePair `json:"values"`
+}
+
+func (ss SampleStream) String() string {
+	vals := make([]string, len(ss.Values))
+	for i, v := range ss.Values {
+		vals[i] = v.String()
+	}
+	return fmt.Sprintf("%s =>\n%s", ss.Metric, strings.Join(vals, "\n"))
+}
+
+// Value is a generic interface for values resulting from a query evaluation.
+type Value interface {
+	Type() ValueType
+	String() string
+}
+
+func (Matrix) Type() ValueType  { return ValMatrix }
+func (Vector) Type() ValueType  { return ValVector }
+func (*Scalar) Type() ValueType { return ValScalar }
+func (*String) Type() ValueType { return ValString }
+
+type ValueType int
+
+const (
+	ValNone ValueType = iota
+	ValScalar
+	ValVector
+	ValMatrix
+	ValString
+)
+
+// MarshalJSON implements json.Marshaler.
+func (et ValueType) MarshalJSON() ([]byte, error) {
+	return json.Marshal(et.String())
+}
+
+func (et *ValueType) UnmarshalJSON(b []byte) error {
+	var s string
+	if err := json.Unmarshal(b, &s); err != nil {
+		return err
+	}
+	switch s {
+	case "<ValNone>":
+		*et = ValNone
+	case "scalar":
+		*et = ValScalar
+	case "vector":
+		*et = ValVector
+	case "matrix":
+		*et = ValMatrix
+	case "string":
+		*et = ValString
+	default:
+		return fmt.Errorf("unknown value type %q", s)
+	}
+	return nil
+}
+
+func (e ValueType) String() string {
+	switch e {
+	case ValNone:
+		return "<ValNone>"
+	case ValScalar:
+		return "scalar"
+	case ValVector:
+		return "vector"
+	case ValMatrix:
+		return "matrix"
+	case ValString:
+		return "string"
+	}
+	panic("ValueType.String: unhandled value type")
+}
+
+// Scalar is a scalar value evaluated at the set timestamp.
+type Scalar struct {
+	Value     SampleValue `json:"value"`
+	Timestamp Time        `json:"timestamp"`
+}
+
+func (s Scalar) String() string {
+	return fmt.Sprintf("scalar: %v @[%v]", s.Value, s.Timestamp)
+}
+
+// MarshalJSON implements json.Marshaler.
+func (s Scalar) MarshalJSON() ([]byte, error) {
+	v := strconv.FormatFloat(float64(s.Value), 'f', -1, 64)
+	return json.Marshal([...]interface{}{s.Timestamp, string(v)})
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *Scalar) UnmarshalJSON(b []byte) error {
+	var f string
+	v := [...]interface{}{&s.Timestamp, &f}
+
+	if err := json.Unmarshal(b, &v); err != nil {
+		return err
+	}
+
+	value, err := strconv.ParseFloat(f, 64)
+	if err != nil {
+		return fmt.Errorf("error parsing sample value: %s", err)
+	}
+	s.Value = SampleValue(value)
+	return nil
+}
+
+// String is a string value evaluated at the set timestamp.
+type String struct {
+	Value     string `json:"value"`
+	Timestamp Time   `json:"timestamp"`
+}
+
+func (s *String) String() string {
+	return s.Value
+}
+
+// MarshalJSON implements json.Marshaler.
+func (s String) MarshalJSON() ([]byte, error) {
+	return json.Marshal([]interface{}{s.Timestamp, s.Value})
+}
+
+// UnmarshalJSON implements json.Unmarshaler.
+func (s *String) UnmarshalJSON(b []byte) error {
+	v := [...]interface{}{&s.Timestamp, &s.Value}
+	return json.Unmarshal(b, &v)
+}
+
+// Vector is basically only an alias for Samples, but the
+// contract is that in a Vector, all Samples have the same timestamp.
+type Vector []*Sample
+
+func (vec Vector) String() string {
+	entries := make([]string, len(vec))
+	for i, s := range vec {
+		entries[i] = s.String()
+	}
+	return strings.Join(entries, "\n")
+}
+
+func (vec Vector) Len() int      { return len(vec) }
+func (vec Vector) Swap(i, j int) { vec[i], vec[j] = vec[j], vec[i] }
+
+// Less compares first the metrics, then the timestamp.
+func (vec Vector) Less(i, j int) bool {
+	switch {
+	case vec[i].Metric.Before(vec[j].Metric):
+		return true
+	case vec[j].Metric.Before(vec[i].Metric):
+		return false
+	case vec[i].Timestamp.Before(vec[j].Timestamp):
+		return true
+	default:
+		return false
+	}
+}
+
+// Equal compares two sets of samples and returns true if they are equal.
+func (vec Vector) Equal(o Vector) bool {
+	if len(vec) != len(o) {
+		return false
+	}
+
+	for i, sample := range vec {
+		if !sample.Equal(o[i]) {
+			return false
+		}
+	}
+	return true
+}
+
+// Matrix is a list of time series.
+type Matrix []*SampleStream
+
+func (m Matrix) Len() int           { return len(m) }
+func (m Matrix) Less(i, j int) bool { return m[i].Metric.Before(m[j].Metric) }
+func (m Matrix) Swap(i, j int)      { m[i], m[j] = m[j], m[i] }
+
+func (mat Matrix) String() string {
+	matCp := make(Matrix, len(mat))
+	copy(matCp, mat)
+	sort.Sort(matCp)
+
+	strs := make([]string, len(matCp))
+
+	for i, ss := range matCp {
+		strs[i] = ss.String()
+	}
+
+	return strings.Join(strs, "\n")
+}

vendor/github.com/prometheus/procfs/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

vendor/github.com/prometheus/procfs/NOTICE

@@ -0,0 +1,7 @@
+procfs provides functions to retrieve system, kernel and process
+metrics from the pseudo-filesystem proc.
+
+Copyright 2014-2015 The Prometheus Authors
+
+This product includes software developed at
+SoundCloud Ltd. (http://soundcloud.com/).

vendor/github.com/prometheus/procfs/buddyinfo.go

@@ -0,0 +1,95 @@
+// Copyright 2017 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// A BuddyInfo is the details parsed from /proc/buddyinfo.
+// The data is comprised of an array of free fragments of each size.
+// The sizes are 2^n*PAGE_SIZE, where n is the array index.
+type BuddyInfo struct {
+	Node  string
+	Zone  string
+	Sizes []float64
+}
+
+// NewBuddyInfo reads the buddyinfo statistics.
+func NewBuddyInfo() ([]BuddyInfo, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return nil, err
+	}
+
+	return fs.NewBuddyInfo()
+}
+
+// NewBuddyInfo reads the buddyinfo statistics from the specified `proc` filesystem.
+func (fs FS) NewBuddyInfo() ([]BuddyInfo, error) {
+	file, err := os.Open(fs.Path("buddyinfo"))
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	return parseBuddyInfo(file)
+}
+
+func parseBuddyInfo(r io.Reader) ([]BuddyInfo, error) {
+	var (
+		buddyInfo   = []BuddyInfo{}
+		scanner     = bufio.NewScanner(r)
+		bucketCount = -1
+	)
+
+	for scanner.Scan() {
+		var err error
+		line := scanner.Text()
+		parts := strings.Fields(line)
+
+		if len(parts) < 4 {
+			return nil, fmt.Errorf("invalid number of fields when parsing buddyinfo")
+		}
+
+		node := strings.TrimRight(parts[1], ",")
+		zone := strings.TrimRight(parts[3], ",")
+		arraySize := len(parts[4:])
+
+		if bucketCount == -1 {
+			bucketCount = arraySize
+		} else {
+			if bucketCount != arraySize {
+				return nil, fmt.Errorf("mismatch in number of buddyinfo buckets, previous count %d, new count %d", bucketCount, arraySize)
+			}
+		}
+
+		sizes := make([]float64, arraySize)
+		for i := 0; i < arraySize; i++ {
+			sizes[i], err = strconv.ParseFloat(parts[i+4], 64)
+			if err != nil {
+				return nil, fmt.Errorf("invalid value in buddyinfo: %s", err)
+			}
+		}
+
+		buddyInfo = append(buddyInfo, BuddyInfo{node, zone, sizes})
+	}
+
+	return buddyInfo, scanner.Err()
+}

vendor/github.com/prometheus/procfs/doc.go

@@ -0,0 +1,45 @@
+// Copyright 2014 Prometheus Team
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package procfs provides functions to retrieve system, kernel and process
+// metrics from the pseudo-filesystem proc.
+//
+// Example:
+//
+//    package main
+//
+//    import (
+//    	"fmt"
+//    	"log"
+//
+//    	"github.com/prometheus/procfs"
+//    )
+//
+//    func main() {
+//    	p, err := procfs.Self()
+//    	if err != nil {
+//    		log.Fatalf("could not get process: %s", err)
+//    	}
+//
+//    	stat, err := p.NewStat()
+//    	if err != nil {
+//    		log.Fatalf("could not get process stat: %s", err)
+//    	}
+//
+//    	fmt.Printf("command:  %s\n", stat.Comm)
+//    	fmt.Printf("cpu time: %fs\n", stat.CPUTime())
+//    	fmt.Printf("vsize:    %dB\n", stat.VirtualMemory())
+//    	fmt.Printf("rss:      %dB\n", stat.ResidentMemory())
+//    }
+//
+package procfs

vendor/github.com/prometheus/procfs/fs.go

@@ -0,0 +1,82 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"fmt"
+	"os"
+	"path"
+
+	"github.com/prometheus/procfs/nfs"
+	"github.com/prometheus/procfs/xfs"
+)
+
+// FS represents the pseudo-filesystem proc, which provides an interface to
+// kernel data structures.
+type FS string
+
+// DefaultMountPoint is the common mount point of the proc filesystem.
+const DefaultMountPoint = "/proc"
+
+// NewFS returns a new FS mounted under the given mountPoint. It will error
+// if the mount point can't be read.
+func NewFS(mountPoint string) (FS, error) {
+	info, err := os.Stat(mountPoint)
+	if err != nil {
+		return "", fmt.Errorf("could not read %s: %s", mountPoint, err)
+	}
+	if !info.IsDir() {
+		return "", fmt.Errorf("mount point %s is not a directory", mountPoint)
+	}
+
+	return FS(mountPoint), nil
+}
+
+// Path returns the path of the given subsystem relative to the procfs root.
+func (fs FS) Path(p ...string) string {
+	return path.Join(append([]string{string(fs)}, p...)...)
+}
+
+// XFSStats retrieves XFS filesystem runtime statistics.
+func (fs FS) XFSStats() (*xfs.Stats, error) {
+	f, err := os.Open(fs.Path("fs/xfs/stat"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return xfs.ParseStats(f)
+}
+
+// NFSClientRPCStats retrieves NFS client RPC statistics.
+func (fs FS) NFSClientRPCStats() (*nfs.ClientRPCStats, error) {
+	f, err := os.Open(fs.Path("net/rpc/nfs"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return nfs.ParseClientRPCStats(f)
+}
+
+// NFSdServerRPCStats retrieves NFS daemon RPC statistics.
+func (fs FS) NFSdServerRPCStats() (*nfs.ServerRPCStats, error) {
+	f, err := os.Open(fs.Path("net/rpc/nfsd"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return nfs.ParseServerRPCStats(f)
+}

vendor/github.com/prometheus/procfs/internal/util/parse.go

@@ -0,0 +1,46 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package util
+
+import "strconv"
+
+// ParseUint32s parses a slice of strings into a slice of uint32s.
+func ParseUint32s(ss []string) ([]uint32, error) {
+	us := make([]uint32, 0, len(ss))
+	for _, s := range ss {
+		u, err := strconv.ParseUint(s, 10, 32)
+		if err != nil {
+			return nil, err
+		}
+
+		us = append(us, uint32(u))
+	}
+
+	return us, nil
+}
+
+// ParseUint64s parses a slice of strings into a slice of uint64s.
+func ParseUint64s(ss []string) ([]uint64, error) {
+	us := make([]uint64, 0, len(ss))
+	for _, s := range ss {
+		u, err := strconv.ParseUint(s, 10, 64)
+		if err != nil {
+			return nil, err
+		}
+
+		us = append(us, u)
+	}
+
+	return us, nil
+}

vendor/github.com/prometheus/procfs/ipvs.go

@@ -0,0 +1,259 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"encoding/hex"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// IPVSStats holds IPVS statistics, as exposed by the kernel in `/proc/net/ip_vs_stats`.
+type IPVSStats struct {
+	// Total count of connections.
+	Connections uint64
+	// Total incoming packages processed.
+	IncomingPackets uint64
+	// Total outgoing packages processed.
+	OutgoingPackets uint64
+	// Total incoming traffic.
+	IncomingBytes uint64
+	// Total outgoing traffic.
+	OutgoingBytes uint64
+}
+
+// IPVSBackendStatus holds current metrics of one virtual / real address pair.
+type IPVSBackendStatus struct {
+	// The local (virtual) IP address.
+	LocalAddress net.IP
+	// The remote (real) IP address.
+	RemoteAddress net.IP
+	// The local (virtual) port.
+	LocalPort uint16
+	// The remote (real) port.
+	RemotePort uint16
+	// The local firewall mark
+	LocalMark string
+	// The transport protocol (TCP, UDP).
+	Proto string
+	// The current number of active connections for this virtual/real address pair.
+	ActiveConn uint64
+	// The current number of inactive connections for this virtual/real address pair.
+	InactConn uint64
+	// The current weight of this virtual/real address pair.
+	Weight uint64
+}
+
+// NewIPVSStats reads the IPVS statistics.
+func NewIPVSStats() (IPVSStats, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+
+	return fs.NewIPVSStats()
+}
+
+// NewIPVSStats reads the IPVS statistics from the specified `proc` filesystem.
+func (fs FS) NewIPVSStats() (IPVSStats, error) {
+	file, err := os.Open(fs.Path("net/ip_vs_stats"))
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	defer file.Close()
+
+	return parseIPVSStats(file)
+}
+
+// parseIPVSStats performs the actual parsing of `ip_vs_stats`.
+func parseIPVSStats(file io.Reader) (IPVSStats, error) {
+	var (
+		statContent []byte
+		statLines   []string
+		statFields  []string
+		stats       IPVSStats
+	)
+
+	statContent, err := ioutil.ReadAll(file)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+
+	statLines = strings.SplitN(string(statContent), "\n", 4)
+	if len(statLines) != 4 {
+		return IPVSStats{}, errors.New("ip_vs_stats corrupt: too short")
+	}
+
+	statFields = strings.Fields(statLines[2])
+	if len(statFields) != 5 {
+		return IPVSStats{}, errors.New("ip_vs_stats corrupt: unexpected number of fields")
+	}
+
+	stats.Connections, err = strconv.ParseUint(statFields[0], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	stats.IncomingPackets, err = strconv.ParseUint(statFields[1], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	stats.OutgoingPackets, err = strconv.ParseUint(statFields[2], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	stats.IncomingBytes, err = strconv.ParseUint(statFields[3], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+	stats.OutgoingBytes, err = strconv.ParseUint(statFields[4], 16, 64)
+	if err != nil {
+		return IPVSStats{}, err
+	}
+
+	return stats, nil
+}
+
+// NewIPVSBackendStatus reads and returns the status of all (virtual,real) server pairs.
+func NewIPVSBackendStatus() ([]IPVSBackendStatus, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return []IPVSBackendStatus{}, err
+	}
+
+	return fs.NewIPVSBackendStatus()
+}
+
+// NewIPVSBackendStatus reads and returns the status of all (virtual,real) server pairs from the specified `proc` filesystem.
+func (fs FS) NewIPVSBackendStatus() ([]IPVSBackendStatus, error) {
+	file, err := os.Open(fs.Path("net/ip_vs"))
+	if err != nil {
+		return nil, err
+	}
+	defer file.Close()
+
+	return parseIPVSBackendStatus(file)
+}
+
+func parseIPVSBackendStatus(file io.Reader) ([]IPVSBackendStatus, error) {
+	var (
+		status       []IPVSBackendStatus
+		scanner      = bufio.NewScanner(file)
+		proto        string
+		localMark    string
+		localAddress net.IP
+		localPort    uint16
+		err          error
+	)
+
+	for scanner.Scan() {
+		fields := strings.Fields(scanner.Text())
+		if len(fields) == 0 {
+			continue
+		}
+		switch {
+		case fields[0] == "IP" || fields[0] == "Prot" || fields[1] == "RemoteAddress:Port":
+			continue
+		case fields[0] == "TCP" || fields[0] == "UDP":
+			if len(fields) < 2 {
+				continue
+			}
+			proto = fields[0]
+			localMark = ""
+			localAddress, localPort, err = parseIPPort(fields[1])
+			if err != nil {
+				return nil, err
+			}
+		case fields[0] == "FWM":
+			if len(fields) < 2 {
+				continue
+			}
+			proto = fields[0]
+			localMark = fields[1]
+			localAddress = nil
+			localPort = 0
+		case fields[0] == "->":
+			if len(fields) < 6 {
+				continue
+			}
+			remoteAddress, remotePort, err := parseIPPort(fields[1])
+			if err != nil {
+				return nil, err
+			}
+			weight, err := strconv.ParseUint(fields[3], 10, 64)
+			if err != nil {
+				return nil, err
+			}
+			activeConn, err := strconv.ParseUint(fields[4], 10, 64)
+			if err != nil {
+				return nil, err
+			}
+			inactConn, err := strconv.ParseUint(fields[5], 10, 64)
+			if err != nil {
+				return nil, err
+			}
+			status = append(status, IPVSBackendStatus{
+				LocalAddress:  localAddress,
+				LocalPort:     localPort,
+				LocalMark:     localMark,
+				RemoteAddress: remoteAddress,
+				RemotePort:    remotePort,
+				Proto:         proto,
+				Weight:        weight,
+				ActiveConn:    activeConn,
+				InactConn:     inactConn,
+			})
+		}
+	}
+	return status, nil
+}
+
+func parseIPPort(s string) (net.IP, uint16, error) {
+	var (
+		ip  net.IP
+		err error
+	)
+
+	switch len(s) {
+	case 13:
+		ip, err = hex.DecodeString(s[0:8])
+		if err != nil {
+			return nil, 0, err
+		}
+	case 46:
+		ip = net.ParseIP(s[1:40])
+		if ip == nil {
+			return nil, 0, fmt.Errorf("invalid IPv6 address: %s", s[1:40])
+		}
+	default:
+		return nil, 0, fmt.Errorf("unexpected IP:Port: %s", s)
+	}
+
+	portString := s[len(s)-4:]
+	if len(portString) != 4 {
+		return nil, 0, fmt.Errorf("unexpected port string format: %s", portString)
+	}
+	port, err := strconv.ParseUint(portString, 16, 16)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	return ip, uint16(port), nil
+}

vendor/github.com/prometheus/procfs/mdstat.go

@@ -0,0 +1,151 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"fmt"
+	"io/ioutil"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+var (
+	statuslineRE = regexp.MustCompile(`(\d+) blocks .*\[(\d+)/(\d+)\] \[[U_]+\]`)
+	buildlineRE  = regexp.MustCompile(`\((\d+)/\d+\)`)
+)
+
+// MDStat holds info parsed from /proc/mdstat.
+type MDStat struct {
+	// Name of the device.
+	Name string
+	// activity-state of the device.
+	ActivityState string
+	// Number of active disks.
+	DisksActive int64
+	// Total number of disks the device consists of.
+	DisksTotal int64
+	// Number of blocks the device holds.
+	BlocksTotal int64
+	// Number of blocks on the device that are in sync.
+	BlocksSynced int64
+}
+
+// ParseMDStat parses an mdstat-file and returns a struct with the relevant infos.
+func (fs FS) ParseMDStat() (mdstates []MDStat, err error) {
+	mdStatusFilePath := fs.Path("mdstat")
+	content, err := ioutil.ReadFile(mdStatusFilePath)
+	if err != nil {
+		return []MDStat{}, fmt.Errorf("error parsing %s: %s", mdStatusFilePath, err)
+	}
+
+	mdStates := []MDStat{}
+	lines := strings.Split(string(content), "\n")
+	for i, l := range lines {
+		if l == "" {
+			continue
+		}
+		if l[0] == ' ' {
+			continue
+		}
+		if strings.HasPrefix(l, "Personalities") || strings.HasPrefix(l, "unused") {
+			continue
+		}
+
+		mainLine := strings.Split(l, " ")
+		if len(mainLine) < 3 {
+			return mdStates, fmt.Errorf("error parsing mdline: %s", l)
+		}
+		mdName := mainLine[0]
+		activityState := mainLine[2]
+
+		if len(lines) <= i+3 {
+			return mdStates, fmt.Errorf(
+				"error parsing %s: too few lines for md device %s",
+				mdStatusFilePath,
+				mdName,
+			)
+		}
+
+		active, total, size, err := evalStatusline(lines[i+1])
+		if err != nil {
+			return mdStates, fmt.Errorf("error parsing %s: %s", mdStatusFilePath, err)
+		}
+
+		// j is the line number of the syncing-line.
+		j := i + 2
+		if strings.Contains(lines[i+2], "bitmap") { // skip bitmap line
+			j = i + 3
+		}
+
+		// If device is syncing at the moment, get the number of currently
+		// synced bytes, otherwise that number equals the size of the device.
+		syncedBlocks := size
+		if strings.Contains(lines[j], "recovery") || strings.Contains(lines[j], "resync") {
+			syncedBlocks, err = evalBuildline(lines[j])
+			if err != nil {
+				return mdStates, fmt.Errorf("error parsing %s: %s", mdStatusFilePath, err)
+			}
+		}
+
+		mdStates = append(mdStates, MDStat{
+			Name:          mdName,
+			ActivityState: activityState,
+			DisksActive:   active,
+			DisksTotal:    total,
+			BlocksTotal:   size,
+			BlocksSynced:  syncedBlocks,
+		})
+	}
+
+	return mdStates, nil
+}
+
+func evalStatusline(statusline string) (active, total, size int64, err error) {
+	matches := statuslineRE.FindStringSubmatch(statusline)
+	if len(matches) != 4 {
+		return 0, 0, 0, fmt.Errorf("unexpected statusline: %s", statusline)
+	}
+
+	size, err = strconv.ParseInt(matches[1], 10, 64)
+	if err != nil {
+		return 0, 0, 0, fmt.Errorf("unexpected statusline %s: %s", statusline, err)
+	}
+
+	total, err = strconv.ParseInt(matches[2], 10, 64)
+	if err != nil {
+		return 0, 0, 0, fmt.Errorf("unexpected statusline %s: %s", statusline, err)
+	}
+
+	active, err = strconv.ParseInt(matches[3], 10, 64)
+	if err != nil {
+		return 0, 0, 0, fmt.Errorf("unexpected statusline %s: %s", statusline, err)
+	}
+
+	return active, total, size, nil
+}
+
+func evalBuildline(buildline string) (syncedBlocks int64, err error) {
+	matches := buildlineRE.FindStringSubmatch(buildline)
+	if len(matches) != 2 {
+		return 0, fmt.Errorf("unexpected buildline: %s", buildline)
+	}
+
+	syncedBlocks, err = strconv.ParseInt(matches[1], 10, 64)
+	if err != nil {
+		return 0, fmt.Errorf("%s in buildline: %s", err, buildline)
+	}
+
+	return syncedBlocks, nil
+}

vendor/github.com/prometheus/procfs/mountstats.go

@@ -0,0 +1,569 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+// While implementing parsing of /proc/[pid]/mountstats, this blog was used
+// heavily as a reference:
+//   https://utcc.utoronto.ca/~cks/space/blog/linux/NFSMountstatsIndex
+//
+// Special thanks to Chris Siebenmann for all of his posts explaining the
+// various statistics available for NFS.
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// Constants shared between multiple functions.
+const (
+	deviceEntryLen = 8
+
+	fieldBytesLen  = 8
+	fieldEventsLen = 27
+
+	statVersion10 = "1.0"
+	statVersion11 = "1.1"
+
+	fieldTransport10Len = 10
+	fieldTransport11Len = 13
+)
+
+// A Mount is a device mount parsed from /proc/[pid]/mountstats.
+type Mount struct {
+	// Name of the device.
+	Device string
+	// The mount point of the device.
+	Mount string
+	// The filesystem type used by the device.
+	Type string
+	// If available additional statistics related to this Mount.
+	// Use a type assertion to determine if additional statistics are available.
+	Stats MountStats
+}
+
+// A MountStats is a type which contains detailed statistics for a specific
+// type of Mount.
+type MountStats interface {
+	mountStats()
+}
+
+// A MountStatsNFS is a MountStats implementation for NFSv3 and v4 mounts.
+type MountStatsNFS struct {
+	// The version of statistics provided.
+	StatVersion string
+	// The age of the NFS mount.
+	Age time.Duration
+	// Statistics related to byte counters for various operations.
+	Bytes NFSBytesStats
+	// Statistics related to various NFS event occurrences.
+	Events NFSEventsStats
+	// Statistics broken down by filesystem operation.
+	Operations []NFSOperationStats
+	// Statistics about the NFS RPC transport.
+	Transport NFSTransportStats
+}
+
+// mountStats implements MountStats.
+func (m MountStatsNFS) mountStats() {}
+
+// A NFSBytesStats contains statistics about the number of bytes read and written
+// by an NFS client to and from an NFS server.
+type NFSBytesStats struct {
+	// Number of bytes read using the read() syscall.
+	Read uint64
+	// Number of bytes written using the write() syscall.
+	Write uint64
+	// Number of bytes read using the read() syscall in O_DIRECT mode.
+	DirectRead uint64
+	// Number of bytes written using the write() syscall in O_DIRECT mode.
+	DirectWrite uint64
+	// Number of bytes read from the NFS server, in total.
+	ReadTotal uint64
+	// Number of bytes written to the NFS server, in total.
+	WriteTotal uint64
+	// Number of pages read directly via mmap()'d files.
+	ReadPages uint64
+	// Number of pages written directly via mmap()'d files.
+	WritePages uint64
+}
+
+// A NFSEventsStats contains statistics about NFS event occurrences.
+type NFSEventsStats struct {
+	// Number of times cached inode attributes are re-validated from the server.
+	InodeRevalidate uint64
+	// Number of times cached dentry nodes are re-validated from the server.
+	DnodeRevalidate uint64
+	// Number of times an inode cache is cleared.
+	DataInvalidate uint64
+	// Number of times cached inode attributes are invalidated.
+	AttributeInvalidate uint64
+	// Number of times files or directories have been open()'d.
+	VFSOpen uint64
+	// Number of times a directory lookup has occurred.
+	VFSLookup uint64
+	// Number of times permissions have been checked.
+	VFSAccess uint64
+	// Number of updates (and potential writes) to pages.
+	VFSUpdatePage uint64
+	// Number of pages read directly via mmap()'d files.
+	VFSReadPage uint64
+	// Number of times a group of pages have been read.
+	VFSReadPages uint64
+	// Number of pages written directly via mmap()'d files.
+	VFSWritePage uint64
+	// Number of times a group of pages have been written.
+	VFSWritePages uint64
+	// Number of times directory entries have been read with getdents().
+	VFSGetdents uint64
+	// Number of times attributes have been set on inodes.
+	VFSSetattr uint64
+	// Number of pending writes that have been forcefully flushed to the server.
+	VFSFlush uint64
+	// Number of times fsync() has been called on directories and files.
+	VFSFsync uint64
+	// Number of times locking has been attempted on a file.
+	VFSLock uint64
+	// Number of times files have been closed and released.
+	VFSFileRelease uint64
+	// Unknown.  Possibly unused.
+	CongestionWait uint64
+	// Number of times files have been truncated.
+	Truncation uint64
+	// Number of times a file has been grown due to writes beyond its existing end.
+	WriteExtension uint64
+	// Number of times a file was removed while still open by another process.
+	SillyRename uint64
+	// Number of times the NFS server gave less data than expected while reading.
+	ShortRead uint64
+	// Number of times the NFS server wrote less data than expected while writing.
+	ShortWrite uint64
+	// Number of times the NFS server indicated EJUKEBOX; retrieving data from
+	// offline storage.
+	JukeboxDelay uint64
+	// Number of NFS v4.1+ pNFS reads.
+	PNFSRead uint64
+	// Number of NFS v4.1+ pNFS writes.
+	PNFSWrite uint64
+}
+
+// A NFSOperationStats contains statistics for a single operation.
+type NFSOperationStats struct {
+	// The name of the operation.
+	Operation string
+	// Number of requests performed for this operation.
+	Requests uint64
+	// Number of times an actual RPC request has been transmitted for this operation.
+	Transmissions uint64
+	// Number of times a request has had a major timeout.
+	MajorTimeouts uint64
+	// Number of bytes sent for this operation, including RPC headers and payload.
+	BytesSent uint64
+	// Number of bytes received for this operation, including RPC headers and payload.
+	BytesReceived uint64
+	// Duration all requests spent queued for transmission before they were sent.
+	CumulativeQueueTime time.Duration
+	// Duration it took to get a reply back after the request was transmitted.
+	CumulativeTotalResponseTime time.Duration
+	// Duration from when a request was enqueued to when it was completely handled.
+	CumulativeTotalRequestTime time.Duration
+}
+
+// A NFSTransportStats contains statistics for the NFS mount RPC requests and
+// responses.
+type NFSTransportStats struct {
+	// The local port used for the NFS mount.
+	Port uint64
+	// Number of times the client has had to establish a connection from scratch
+	// to the NFS server.
+	Bind uint64
+	// Number of times the client has made a TCP connection to the NFS server.
+	Connect uint64
+	// Duration (in jiffies, a kernel internal unit of time) the NFS mount has
+	// spent waiting for connections to the server to be established.
+	ConnectIdleTime uint64
+	// Duration since the NFS mount last saw any RPC traffic.
+	IdleTime time.Duration
+	// Number of RPC requests for this mount sent to the NFS server.
+	Sends uint64
+	// Number of RPC responses for this mount received from the NFS server.
+	Receives uint64
+	// Number of times the NFS server sent a response with a transaction ID
+	// unknown to this client.
+	BadTransactionIDs uint64
+	// A running counter, incremented on each request as the current difference
+	// ebetween sends and receives.
+	CumulativeActiveRequests uint64
+	// A running counter, incremented on each request by the current backlog
+	// queue size.
+	CumulativeBacklog uint64
+
+	// Stats below only available with stat version 1.1.
+
+	// Maximum number of simultaneously active RPC requests ever used.
+	MaximumRPCSlotsUsed uint64
+	// A running counter, incremented on each request as the current size of the
+	// sending queue.
+	CumulativeSendingQueue uint64
+	// A running counter, incremented on each request as the current size of the
+	// pending queue.
+	CumulativePendingQueue uint64
+}
+
+// parseMountStats parses a /proc/[pid]/mountstats file and returns a slice
+// of Mount structures containing detailed information about each mount.
+// If available, statistics for each mount are parsed as well.
+func parseMountStats(r io.Reader) ([]*Mount, error) {
+	const (
+		device            = "device"
+		statVersionPrefix = "statvers="
+
+		nfs3Type = "nfs"
+		nfs4Type = "nfs4"
+	)
+
+	var mounts []*Mount
+
+	s := bufio.NewScanner(r)
+	for s.Scan() {
+		// Only look for device entries in this function
+		ss := strings.Fields(string(s.Bytes()))
+		if len(ss) == 0 || ss[0] != device {
+			continue
+		}
+
+		m, err := parseMount(ss)
+		if err != nil {
+			return nil, err
+		}
+
+		// Does this mount also possess statistics information?
+		if len(ss) > deviceEntryLen {
+			// Only NFSv3 and v4 are supported for parsing statistics
+			if m.Type != nfs3Type && m.Type != nfs4Type {
+				return nil, fmt.Errorf("cannot parse MountStats for fstype %q", m.Type)
+			}
+
+			statVersion := strings.TrimPrefix(ss[8], statVersionPrefix)
+
+			stats, err := parseMountStatsNFS(s, statVersion)
+			if err != nil {
+				return nil, err
+			}
+
+			m.Stats = stats
+		}
+
+		mounts = append(mounts, m)
+	}
+
+	return mounts, s.Err()
+}
+
+// parseMount parses an entry in /proc/[pid]/mountstats in the format:
+//   device [device] mounted on [mount] with fstype [type]
+func parseMount(ss []string) (*Mount, error) {
+	if len(ss) < deviceEntryLen {
+		return nil, fmt.Errorf("invalid device entry: %v", ss)
+	}
+
+	// Check for specific words appearing at specific indices to ensure
+	// the format is consistent with what we expect
+	format := []struct {
+		i int
+		s string
+	}{
+		{i: 0, s: "device"},
+		{i: 2, s: "mounted"},
+		{i: 3, s: "on"},
+		{i: 5, s: "with"},
+		{i: 6, s: "fstype"},
+	}
+
+	for _, f := range format {
+		if ss[f.i] != f.s {
+			return nil, fmt.Errorf("invalid device entry: %v", ss)
+		}
+	}
+
+	return &Mount{
+		Device: ss[1],
+		Mount:  ss[4],
+		Type:   ss[7],
+	}, nil
+}
+
+// parseMountStatsNFS parses a MountStatsNFS by scanning additional information
+// related to NFS statistics.
+func parseMountStatsNFS(s *bufio.Scanner, statVersion string) (*MountStatsNFS, error) {
+	// Field indicators for parsing specific types of data
+	const (
+		fieldAge        = "age:"
+		fieldBytes      = "bytes:"
+		fieldEvents     = "events:"
+		fieldPerOpStats = "per-op"
+		fieldTransport  = "xprt:"
+	)
+
+	stats := &MountStatsNFS{
+		StatVersion: statVersion,
+	}
+
+	for s.Scan() {
+		ss := strings.Fields(string(s.Bytes()))
+		if len(ss) == 0 {
+			break
+		}
+		if len(ss) < 2 {
+			return nil, fmt.Errorf("not enough information for NFS stats: %v", ss)
+		}
+
+		switch ss[0] {
+		case fieldAge:
+			// Age integer is in seconds
+			d, err := time.ParseDuration(ss[1] + "s")
+			if err != nil {
+				return nil, err
+			}
+
+			stats.Age = d
+		case fieldBytes:
+			bstats, err := parseNFSBytesStats(ss[1:])
+			if err != nil {
+				return nil, err
+			}
+
+			stats.Bytes = *bstats
+		case fieldEvents:
+			estats, err := parseNFSEventsStats(ss[1:])
+			if err != nil {
+				return nil, err
+			}
+
+			stats.Events = *estats
+		case fieldTransport:
+			if len(ss) < 3 {
+				return nil, fmt.Errorf("not enough information for NFS transport stats: %v", ss)
+			}
+
+			tstats, err := parseNFSTransportStats(ss[2:], statVersion)
+			if err != nil {
+				return nil, err
+			}
+
+			stats.Transport = *tstats
+		}
+
+		// When encountering "per-operation statistics", we must break this
+		// loop and parse them separately to ensure we can terminate parsing
+		// before reaching another device entry; hence why this 'if' statement
+		// is not just another switch case
+		if ss[0] == fieldPerOpStats {
+			break
+		}
+	}
+
+	if err := s.Err(); err != nil {
+		return nil, err
+	}
+
+	// NFS per-operation stats appear last before the next device entry
+	perOpStats, err := parseNFSOperationStats(s)
+	if err != nil {
+		return nil, err
+	}
+
+	stats.Operations = perOpStats
+
+	return stats, nil
+}
+
+// parseNFSBytesStats parses a NFSBytesStats line using an input set of
+// integer fields.
+func parseNFSBytesStats(ss []string) (*NFSBytesStats, error) {
+	if len(ss) != fieldBytesLen {
+		return nil, fmt.Errorf("invalid NFS bytes stats: %v", ss)
+	}
+
+	ns := make([]uint64, 0, fieldBytesLen)
+	for _, s := range ss {
+		n, err := strconv.ParseUint(s, 10, 64)
+		if err != nil {
+			return nil, err
+		}
+
+		ns = append(ns, n)
+	}
+
+	return &NFSBytesStats{
+		Read:        ns[0],
+		Write:       ns[1],
+		DirectRead:  ns[2],
+		DirectWrite: ns[3],
+		ReadTotal:   ns[4],
+		WriteTotal:  ns[5],
+		ReadPages:   ns[6],
+		WritePages:  ns[7],
+	}, nil
+}
+
+// parseNFSEventsStats parses a NFSEventsStats line using an input set of
+// integer fields.
+func parseNFSEventsStats(ss []string) (*NFSEventsStats, error) {
+	if len(ss) != fieldEventsLen {
+		return nil, fmt.Errorf("invalid NFS events stats: %v", ss)
+	}
+
+	ns := make([]uint64, 0, fieldEventsLen)
+	for _, s := range ss {
+		n, err := strconv.ParseUint(s, 10, 64)
+		if err != nil {
+			return nil, err
+		}
+
+		ns = append(ns, n)
+	}
+
+	return &NFSEventsStats{
+		InodeRevalidate:     ns[0],
+		DnodeRevalidate:     ns[1],
+		DataInvalidate:      ns[2],
+		AttributeInvalidate: ns[3],
+		VFSOpen:             ns[4],
+		VFSLookup:           ns[5],
+		VFSAccess:           ns[6],
+		VFSUpdatePage:       ns[7],
+		VFSReadPage:         ns[8],
+		VFSReadPages:        ns[9],
+		VFSWritePage:        ns[10],
+		VFSWritePages:       ns[11],
+		VFSGetdents:         ns[12],
+		VFSSetattr:          ns[13],
+		VFSFlush:            ns[14],
+		VFSFsync:            ns[15],
+		VFSLock:             ns[16],
+		VFSFileRelease:      ns[17],
+		CongestionWait:      ns[18],
+		Truncation:          ns[19],
+		WriteExtension:      ns[20],
+		SillyRename:         ns[21],
+		ShortRead:           ns[22],
+		ShortWrite:          ns[23],
+		JukeboxDelay:        ns[24],
+		PNFSRead:            ns[25],
+		PNFSWrite:           ns[26],
+	}, nil
+}
+
+// parseNFSOperationStats parses a slice of NFSOperationStats by scanning
+// additional information about per-operation statistics until an empty
+// line is reached.
+func parseNFSOperationStats(s *bufio.Scanner) ([]NFSOperationStats, error) {
+	const (
+		// Number of expected fields in each per-operation statistics set
+		numFields = 9
+	)
+
+	var ops []NFSOperationStats
+
+	for s.Scan() {
+		ss := strings.Fields(string(s.Bytes()))
+		if len(ss) == 0 {
+			// Must break when reading a blank line after per-operation stats to
+			// enable top-level function to parse the next device entry
+			break
+		}
+
+		if len(ss) != numFields {
+			return nil, fmt.Errorf("invalid NFS per-operations stats: %v", ss)
+		}
+
+		// Skip string operation name for integers
+		ns := make([]uint64, 0, numFields-1)
+		for _, st := range ss[1:] {
+			n, err := strconv.ParseUint(st, 10, 64)
+			if err != nil {
+				return nil, err
+			}
+
+			ns = append(ns, n)
+		}
+
+		ops = append(ops, NFSOperationStats{
+			Operation:                   strings.TrimSuffix(ss[0], ":"),
+			Requests:                    ns[0],
+			Transmissions:               ns[1],
+			MajorTimeouts:               ns[2],
+			BytesSent:                   ns[3],
+			BytesReceived:               ns[4],
+			CumulativeQueueTime:         time.Duration(ns[5]) * time.Millisecond,
+			CumulativeTotalResponseTime: time.Duration(ns[6]) * time.Millisecond,
+			CumulativeTotalRequestTime:  time.Duration(ns[7]) * time.Millisecond,
+		})
+	}
+
+	return ops, s.Err()
+}
+
+// parseNFSTransportStats parses a NFSTransportStats line using an input set of
+// integer fields matched to a specific stats version.
+func parseNFSTransportStats(ss []string, statVersion string) (*NFSTransportStats, error) {
+	switch statVersion {
+	case statVersion10:
+		if len(ss) != fieldTransport10Len {
+			return nil, fmt.Errorf("invalid NFS transport stats 1.0 statement: %v", ss)
+		}
+	case statVersion11:
+		if len(ss) != fieldTransport11Len {
+			return nil, fmt.Errorf("invalid NFS transport stats 1.1 statement: %v", ss)
+		}
+	default:
+		return nil, fmt.Errorf("unrecognized NFS transport stats version: %q", statVersion)
+	}
+
+	// Allocate enough for v1.1 stats since zero value for v1.1 stats will be okay
+	// in a v1.0 response.
+	//
+	// Note: slice length must be set to length of v1.1 stats to avoid a panic when
+	// only v1.0 stats are present.
+	// See: https://github.com/prometheus/node_exporter/issues/571.
+	ns := make([]uint64, fieldTransport11Len)
+	for i, s := range ss {
+		n, err := strconv.ParseUint(s, 10, 64)
+		if err != nil {
+			return nil, err
+		}
+
+		ns[i] = n
+	}
+
+	return &NFSTransportStats{
+		Port:                     ns[0],
+		Bind:                     ns[1],
+		Connect:                  ns[2],
+		ConnectIdleTime:          ns[3],
+		IdleTime:                 time.Duration(ns[4]) * time.Second,
+		Sends:                    ns[5],
+		Receives:                 ns[6],
+		BadTransactionIDs:        ns[7],
+		CumulativeActiveRequests: ns[8],
+		CumulativeBacklog:        ns[9],
+		MaximumRPCSlotsUsed:      ns[10],
+		CumulativeSendingQueue:   ns[11],
+		CumulativePendingQueue:   ns[12],
+	}, nil
+}

vendor/github.com/prometheus/procfs/net_dev.go

@@ -0,0 +1,216 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"errors"
+	"os"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+// NetDevLine is single line parsed from /proc/net/dev or /proc/[pid]/net/dev.
+type NetDevLine struct {
+	Name         string `json:"name"`          // The name of the interface.
+	RxBytes      uint64 `json:"rx_bytes"`      // Cumulative count of bytes received.
+	RxPackets    uint64 `json:"rx_packets"`    // Cumulative count of packets received.
+	RxErrors     uint64 `json:"rx_errors"`     // Cumulative count of receive errors encountered.
+	RxDropped    uint64 `json:"rx_dropped"`    // Cumulative count of packets dropped while receiving.
+	RxFIFO       uint64 `json:"rx_fifo"`       // Cumulative count of FIFO buffer errors.
+	RxFrame      uint64 `json:"rx_frame"`      // Cumulative count of packet framing errors.
+	RxCompressed uint64 `json:"rx_compressed"` // Cumulative count of compressed packets received by the device driver.
+	RxMulticast  uint64 `json:"rx_multicast"`  // Cumulative count of multicast frames received by the device driver.
+	TxBytes      uint64 `json:"tx_bytes"`      // Cumulative count of bytes transmitted.
+	TxPackets    uint64 `json:"tx_packets"`    // Cumulative count of packets transmitted.
+	TxErrors     uint64 `json:"tx_errors"`     // Cumulative count of transmit errors encountered.
+	TxDropped    uint64 `json:"tx_dropped"`    // Cumulative count of packets dropped while transmitting.
+	TxFIFO       uint64 `json:"tx_fifo"`       // Cumulative count of FIFO buffer errors.
+	TxCollisions uint64 `json:"tx_collisions"` // Cumulative count of collisions detected on the interface.
+	TxCarrier    uint64 `json:"tx_carrier"`    // Cumulative count of carrier losses detected by the device driver.
+	TxCompressed uint64 `json:"tx_compressed"` // Cumulative count of compressed packets transmitted by the device driver.
+}
+
+// NetDev is parsed from /proc/net/dev or /proc/[pid]/net/dev. The map keys
+// are interface names.
+type NetDev map[string]NetDevLine
+
+// NewNetDev returns kernel/system statistics read from /proc/net/dev.
+func NewNetDev() (NetDev, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return nil, err
+	}
+
+	return fs.NewNetDev()
+}
+
+// NewNetDev returns kernel/system statistics read from /proc/net/dev.
+func (fs FS) NewNetDev() (NetDev, error) {
+	return newNetDev(fs.Path("net/dev"))
+}
+
+// NewNetDev returns kernel/system statistics read from /proc/[pid]/net/dev.
+func (p Proc) NewNetDev() (NetDev, error) {
+	return newNetDev(p.path("net/dev"))
+}
+
+// newNetDev creates a new NetDev from the contents of the given file.
+func newNetDev(file string) (NetDev, error) {
+	f, err := os.Open(file)
+	if err != nil {
+		return NetDev{}, err
+	}
+	defer f.Close()
+
+	nd := NetDev{}
+	s := bufio.NewScanner(f)
+	for n := 0; s.Scan(); n++ {
+		// Skip the 2 header lines.
+		if n < 2 {
+			continue
+		}
+
+		line, err := nd.parseLine(s.Text())
+		if err != nil {
+			return nd, err
+		}
+
+		nd[line.Name] = *line
+	}
+
+	return nd, s.Err()
+}
+
+// parseLine parses a single line from the /proc/net/dev file. Header lines
+// must be filtered prior to calling this method.
+func (nd NetDev) parseLine(rawLine string) (*NetDevLine, error) {
+	parts := strings.SplitN(rawLine, ":", 2)
+	if len(parts) != 2 {
+		return nil, errors.New("invalid net/dev line, missing colon")
+	}
+	fields := strings.Fields(strings.TrimSpace(parts[1]))
+
+	var err error
+	line := &NetDevLine{}
+
+	// Interface Name
+	line.Name = strings.TrimSpace(parts[0])
+	if line.Name == "" {
+		return nil, errors.New("invalid net/dev line, empty interface name")
+	}
+
+	// RX
+	line.RxBytes, err = strconv.ParseUint(fields[0], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxPackets, err = strconv.ParseUint(fields[1], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxErrors, err = strconv.ParseUint(fields[2], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxDropped, err = strconv.ParseUint(fields[3], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxFIFO, err = strconv.ParseUint(fields[4], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxFrame, err = strconv.ParseUint(fields[5], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxCompressed, err = strconv.ParseUint(fields[6], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.RxMulticast, err = strconv.ParseUint(fields[7], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+
+	// TX
+	line.TxBytes, err = strconv.ParseUint(fields[8], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxPackets, err = strconv.ParseUint(fields[9], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxErrors, err = strconv.ParseUint(fields[10], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxDropped, err = strconv.ParseUint(fields[11], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxFIFO, err = strconv.ParseUint(fields[12], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxCollisions, err = strconv.ParseUint(fields[13], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxCarrier, err = strconv.ParseUint(fields[14], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+	line.TxCompressed, err = strconv.ParseUint(fields[15], 10, 64)
+	if err != nil {
+		return nil, err
+	}
+
+	return line, nil
+}
+
+// Total aggregates the values across interfaces and returns a new NetDevLine.
+// The Name field will be a sorted comma separated list of interface names.
+func (nd NetDev) Total() NetDevLine {
+	total := NetDevLine{}
+
+	names := make([]string, 0, len(nd))
+	for _, ifc := range nd {
+		names = append(names, ifc.Name)
+		total.RxBytes += ifc.RxBytes
+		total.RxPackets += ifc.RxPackets
+		total.RxPackets += ifc.RxPackets
+		total.RxErrors += ifc.RxErrors
+		total.RxDropped += ifc.RxDropped
+		total.RxFIFO += ifc.RxFIFO
+		total.RxFrame += ifc.RxFrame
+		total.RxCompressed += ifc.RxCompressed
+		total.RxMulticast += ifc.RxMulticast
+		total.TxBytes += ifc.TxBytes
+		total.TxPackets += ifc.TxPackets
+		total.TxErrors += ifc.TxErrors
+		total.TxDropped += ifc.TxDropped
+		total.TxFIFO += ifc.TxFIFO
+		total.TxCollisions += ifc.TxCollisions
+		total.TxCarrier += ifc.TxCarrier
+		total.TxCompressed += ifc.TxCompressed
+	}
+	sort.Strings(names)
+	total.Name = strings.Join(names, ", ")
+
+	return total
+}

vendor/github.com/prometheus/procfs/nfs/nfs.go

@@ -0,0 +1,263 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package nfs implements parsing of /proc/net/rpc/nfsd.
+// Fields are documented in https://www.svennd.be/nfsd-stats-explained-procnetrpcnfsd/
+package nfs
+
+// ReplyCache models the "rc" line.
+type ReplyCache struct {
+	Hits    uint64
+	Misses  uint64
+	NoCache uint64
+}
+
+// FileHandles models the "fh" line.
+type FileHandles struct {
+	Stale        uint64
+	TotalLookups uint64
+	AnonLookups  uint64
+	DirNoCache   uint64
+	NoDirNoCache uint64
+}
+
+// InputOutput models the "io" line.
+type InputOutput struct {
+	Read  uint64
+	Write uint64
+}
+
+// Threads models the "th" line.
+type Threads struct {
+	Threads uint64
+	FullCnt uint64
+}
+
+// ReadAheadCache models the "ra" line.
+type ReadAheadCache struct {
+	CacheSize      uint64
+	CacheHistogram []uint64
+	NotFound       uint64
+}
+
+// Network models the "net" line.
+type Network struct {
+	NetCount   uint64
+	UDPCount   uint64
+	TCPCount   uint64
+	TCPConnect uint64
+}
+
+// ClientRPC models the nfs "rpc" line.
+type ClientRPC struct {
+	RPCCount        uint64
+	Retransmissions uint64
+	AuthRefreshes   uint64
+}
+
+// ServerRPC models the nfsd "rpc" line.
+type ServerRPC struct {
+	RPCCount uint64
+	BadCnt   uint64
+	BadFmt   uint64
+	BadAuth  uint64
+	BadcInt  uint64
+}
+
+// V2Stats models the "proc2" line.
+type V2Stats struct {
+	Null     uint64
+	GetAttr  uint64
+	SetAttr  uint64
+	Root     uint64
+	Lookup   uint64
+	ReadLink uint64
+	Read     uint64
+	WrCache  uint64
+	Write    uint64
+	Create   uint64
+	Remove   uint64
+	Rename   uint64
+	Link     uint64
+	SymLink  uint64
+	MkDir    uint64
+	RmDir    uint64
+	ReadDir  uint64
+	FsStat   uint64
+}
+
+// V3Stats models the "proc3" line.
+type V3Stats struct {
+	Null        uint64
+	GetAttr     uint64
+	SetAttr     uint64
+	Lookup      uint64
+	Access      uint64
+	ReadLink    uint64
+	Read        uint64
+	Write       uint64
+	Create      uint64
+	MkDir       uint64
+	SymLink     uint64
+	MkNod       uint64
+	Remove      uint64
+	RmDir       uint64
+	Rename      uint64
+	Link        uint64
+	ReadDir     uint64
+	ReadDirPlus uint64
+	FsStat      uint64
+	FsInfo      uint64
+	PathConf    uint64
+	Commit      uint64
+}
+
+// ClientV4Stats models the nfs "proc4" line.
+type ClientV4Stats struct {
+	Null               uint64
+	Read               uint64
+	Write              uint64
+	Commit             uint64
+	Open               uint64
+	OpenConfirm        uint64
+	OpenNoattr         uint64
+	OpenDowngrade      uint64
+	Close              uint64
+	Setattr            uint64
+	FsInfo             uint64
+	Renew              uint64
+	SetClientID        uint64
+	SetClientIDConfirm uint64
+	Lock               uint64
+	Lockt              uint64
+	Locku              uint64
+	Access             uint64
+	Getattr            uint64
+	Lookup             uint64
+	LookupRoot         uint64
+	Remove             uint64
+	Rename             uint64
+	Link               uint64
+	Symlink            uint64
+	Create             uint64
+	Pathconf           uint64
+	StatFs             uint64
+	ReadLink           uint64
+	ReadDir            uint64
+	ServerCaps         uint64
+	DelegReturn        uint64
+	GetACL             uint64
+	SetACL             uint64
+	FsLocations        uint64
+	ReleaseLockowner   uint64
+	Secinfo            uint64
+	FsidPresent        uint64
+	ExchangeID         uint64
+	CreateSession      uint64
+	DestroySession     uint64
+	Sequence           uint64
+	GetLeaseTime       uint64
+	ReclaimComplete    uint64
+	LayoutGet          uint64
+	GetDeviceInfo      uint64
+	LayoutCommit       uint64
+	LayoutReturn       uint64
+	SecinfoNoName      uint64
+	TestStateID        uint64
+	FreeStateID        uint64
+	GetDeviceList      uint64
+	BindConnToSession  uint64
+	DestroyClientID    uint64
+	Seek               uint64
+	Allocate           uint64
+	DeAllocate         uint64
+	LayoutStats        uint64
+	Clone              uint64
+}
+
+// ServerV4Stats models the nfsd "proc4" line.
+type ServerV4Stats struct {
+	Null     uint64
+	Compound uint64
+}
+
+// V4Ops models the "proc4ops" line: NFSv4 operations
+// Variable list, see:
+// v4.0 https://tools.ietf.org/html/rfc3010 (38 operations)
+// v4.1 https://tools.ietf.org/html/rfc5661 (58 operations)
+// v4.2 https://tools.ietf.org/html/draft-ietf-nfsv4-minorversion2-41 (71 operations)
+type V4Ops struct {
+	//Values       uint64 // Variable depending on v4.x sub-version. TODO: Will this always at least include the fields in this struct?
+	Op0Unused    uint64
+	Op1Unused    uint64
+	Op2Future    uint64
+	Access       uint64
+	Close        uint64
+	Commit       uint64
+	Create       uint64
+	DelegPurge   uint64
+	DelegReturn  uint64
+	GetAttr      uint64
+	GetFH        uint64
+	Link         uint64
+	Lock         uint64
+	Lockt        uint64
+	Locku        uint64
+	Lookup       uint64
+	LookupRoot   uint64
+	Nverify      uint64
+	Open         uint64
+	OpenAttr     uint64
+	OpenConfirm  uint64
+	OpenDgrd     uint64
+	PutFH        uint64
+	PutPubFH     uint64
+	PutRootFH    uint64
+	Read         uint64
+	ReadDir      uint64
+	ReadLink     uint64
+	Remove       uint64
+	Rename       uint64
+	Renew        uint64
+	RestoreFH    uint64
+	SaveFH       uint64
+	SecInfo      uint64
+	SetAttr      uint64
+	Verify       uint64
+	Write        uint64
+	RelLockOwner uint64
+}
+
+// ClientRPCStats models all stats from /proc/net/rpc/nfs.
+type ClientRPCStats struct {
+	Network       Network
+	ClientRPC     ClientRPC
+	V2Stats       V2Stats
+	V3Stats       V3Stats
+	ClientV4Stats ClientV4Stats
+}
+
+// ServerRPCStats models all stats from /proc/net/rpc/nfsd.
+type ServerRPCStats struct {
+	ReplyCache     ReplyCache
+	FileHandles    FileHandles
+	InputOutput    InputOutput
+	Threads        Threads
+	ReadAheadCache ReadAheadCache
+	Network        Network
+	ServerRPC      ServerRPC
+	V2Stats        V2Stats
+	V3Stats        V3Stats
+	ServerV4Stats  ServerV4Stats
+	V4Ops          V4Ops
+}

vendor/github.com/prometheus/procfs/nfs/parse.go

@@ -0,0 +1,317 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package nfs
+
+import (
+	"fmt"
+)
+
+func parseReplyCache(v []uint64) (ReplyCache, error) {
+	if len(v) != 3 {
+		return ReplyCache{}, fmt.Errorf("invalid ReplyCache line %q", v)
+	}
+
+	return ReplyCache{
+		Hits:    v[0],
+		Misses:  v[1],
+		NoCache: v[2],
+	}, nil
+}
+
+func parseFileHandles(v []uint64) (FileHandles, error) {
+	if len(v) != 5 {
+		return FileHandles{}, fmt.Errorf("invalid FileHandles, line %q", v)
+	}
+
+	return FileHandles{
+		Stale:        v[0],
+		TotalLookups: v[1],
+		AnonLookups:  v[2],
+		DirNoCache:   v[3],
+		NoDirNoCache: v[4],
+	}, nil
+}
+
+func parseInputOutput(v []uint64) (InputOutput, error) {
+	if len(v) != 2 {
+		return InputOutput{}, fmt.Errorf("invalid InputOutput line %q", v)
+	}
+
+	return InputOutput{
+		Read:  v[0],
+		Write: v[1],
+	}, nil
+}
+
+func parseThreads(v []uint64) (Threads, error) {
+	if len(v) != 2 {
+		return Threads{}, fmt.Errorf("invalid Threads line %q", v)
+	}
+
+	return Threads{
+		Threads: v[0],
+		FullCnt: v[1],
+	}, nil
+}
+
+func parseReadAheadCache(v []uint64) (ReadAheadCache, error) {
+	if len(v) != 12 {
+		return ReadAheadCache{}, fmt.Errorf("invalid ReadAheadCache line %q", v)
+	}
+
+	return ReadAheadCache{
+		CacheSize:      v[0],
+		CacheHistogram: v[1:11],
+		NotFound:       v[11],
+	}, nil
+}
+
+func parseNetwork(v []uint64) (Network, error) {
+	if len(v) != 4 {
+		return Network{}, fmt.Errorf("invalid Network line %q", v)
+	}
+
+	return Network{
+		NetCount:   v[0],
+		UDPCount:   v[1],
+		TCPCount:   v[2],
+		TCPConnect: v[3],
+	}, nil
+}
+
+func parseServerRPC(v []uint64) (ServerRPC, error) {
+	if len(v) != 5 {
+		return ServerRPC{}, fmt.Errorf("invalid RPC line %q", v)
+	}
+
+	return ServerRPC{
+		RPCCount: v[0],
+		BadCnt:   v[1],
+		BadFmt:   v[2],
+		BadAuth:  v[3],
+		BadcInt:  v[4],
+	}, nil
+}
+
+func parseClientRPC(v []uint64) (ClientRPC, error) {
+	if len(v) != 3 {
+		return ClientRPC{}, fmt.Errorf("invalid RPC line %q", v)
+	}
+
+	return ClientRPC{
+		RPCCount:        v[0],
+		Retransmissions: v[1],
+		AuthRefreshes:   v[2],
+	}, nil
+}
+
+func parseV2Stats(v []uint64) (V2Stats, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values != 18 {
+		return V2Stats{}, fmt.Errorf("invalid V2Stats line %q", v)
+	}
+
+	return V2Stats{
+		Null:     v[1],
+		GetAttr:  v[2],
+		SetAttr:  v[3],
+		Root:     v[4],
+		Lookup:   v[5],
+		ReadLink: v[6],
+		Read:     v[7],
+		WrCache:  v[8],
+		Write:    v[9],
+		Create:   v[10],
+		Remove:   v[11],
+		Rename:   v[12],
+		Link:     v[13],
+		SymLink:  v[14],
+		MkDir:    v[15],
+		RmDir:    v[16],
+		ReadDir:  v[17],
+		FsStat:   v[18],
+	}, nil
+}
+
+func parseV3Stats(v []uint64) (V3Stats, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values != 22 {
+		return V3Stats{}, fmt.Errorf("invalid V3Stats line %q", v)
+	}
+
+	return V3Stats{
+		Null:        v[1],
+		GetAttr:     v[2],
+		SetAttr:     v[3],
+		Lookup:      v[4],
+		Access:      v[5],
+		ReadLink:    v[6],
+		Read:        v[7],
+		Write:       v[8],
+		Create:      v[9],
+		MkDir:       v[10],
+		SymLink:     v[11],
+		MkNod:       v[12],
+		Remove:      v[13],
+		RmDir:       v[14],
+		Rename:      v[15],
+		Link:        v[16],
+		ReadDir:     v[17],
+		ReadDirPlus: v[18],
+		FsStat:      v[19],
+		FsInfo:      v[20],
+		PathConf:    v[21],
+		Commit:      v[22],
+	}, nil
+}
+
+func parseClientV4Stats(v []uint64) (ClientV4Stats, error) {
+	values := int(v[0])
+	if len(v[1:]) != values {
+		return ClientV4Stats{}, fmt.Errorf("invalid ClientV4Stats line %q", v)
+	}
+
+	// This function currently supports mapping 59 NFS v4 client stats.  Older
+	// kernels may emit fewer stats, so we must detect this and pad out the
+	// values to match the expected slice size.
+	if values < 59 {
+		newValues := make([]uint64, 60)
+		copy(newValues, v)
+		v = newValues
+	}
+
+	return ClientV4Stats{
+		Null:               v[1],
+		Read:               v[2],
+		Write:              v[3],
+		Commit:             v[4],
+		Open:               v[5],
+		OpenConfirm:        v[6],
+		OpenNoattr:         v[7],
+		OpenDowngrade:      v[8],
+		Close:              v[9],
+		Setattr:            v[10],
+		FsInfo:             v[11],
+		Renew:              v[12],
+		SetClientID:        v[13],
+		SetClientIDConfirm: v[14],
+		Lock:               v[15],
+		Lockt:              v[16],
+		Locku:              v[17],
+		Access:             v[18],
+		Getattr:            v[19],
+		Lookup:             v[20],
+		LookupRoot:         v[21],
+		Remove:             v[22],
+		Rename:             v[23],
+		Link:               v[24],
+		Symlink:            v[25],
+		Create:             v[26],
+		Pathconf:           v[27],
+		StatFs:             v[28],
+		ReadLink:           v[29],
+		ReadDir:            v[30],
+		ServerCaps:         v[31],
+		DelegReturn:        v[32],
+		GetACL:             v[33],
+		SetACL:             v[34],
+		FsLocations:        v[35],
+		ReleaseLockowner:   v[36],
+		Secinfo:            v[37],
+		FsidPresent:        v[38],
+		ExchangeID:         v[39],
+		CreateSession:      v[40],
+		DestroySession:     v[41],
+		Sequence:           v[42],
+		GetLeaseTime:       v[43],
+		ReclaimComplete:    v[44],
+		LayoutGet:          v[45],
+		GetDeviceInfo:      v[46],
+		LayoutCommit:       v[47],
+		LayoutReturn:       v[48],
+		SecinfoNoName:      v[49],
+		TestStateID:        v[50],
+		FreeStateID:        v[51],
+		GetDeviceList:      v[52],
+		BindConnToSession:  v[53],
+		DestroyClientID:    v[54],
+		Seek:               v[55],
+		Allocate:           v[56],
+		DeAllocate:         v[57],
+		LayoutStats:        v[58],
+		Clone:              v[59],
+	}, nil
+}
+
+func parseServerV4Stats(v []uint64) (ServerV4Stats, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values != 2 {
+		return ServerV4Stats{}, fmt.Errorf("invalid V4Stats line %q", v)
+	}
+
+	return ServerV4Stats{
+		Null:     v[1],
+		Compound: v[2],
+	}, nil
+}
+
+func parseV4Ops(v []uint64) (V4Ops, error) {
+	values := int(v[0])
+	if len(v[1:]) != values || values < 39 {
+		return V4Ops{}, fmt.Errorf("invalid V4Ops line %q", v)
+	}
+
+	stats := V4Ops{
+		Op0Unused:    v[1],
+		Op1Unused:    v[2],
+		Op2Future:    v[3],
+		Access:       v[4],
+		Close:        v[5],
+		Commit:       v[6],
+		Create:       v[7],
+		DelegPurge:   v[8],
+		DelegReturn:  v[9],
+		GetAttr:      v[10],
+		GetFH:        v[11],
+		Link:         v[12],
+		Lock:         v[13],
+		Lockt:        v[14],
+		Locku:        v[15],
+		Lookup:       v[16],
+		LookupRoot:   v[17],
+		Nverify:      v[18],
+		Open:         v[19],
+		OpenAttr:     v[20],
+		OpenConfirm:  v[21],
+		OpenDgrd:     v[22],
+		PutFH:        v[23],
+		PutPubFH:     v[24],
+		PutRootFH:    v[25],
+		Read:         v[26],
+		ReadDir:      v[27],
+		ReadLink:     v[28],
+		Remove:       v[29],
+		Rename:       v[30],
+		Renew:        v[31],
+		RestoreFH:    v[32],
+		SaveFH:       v[33],
+		SecInfo:      v[34],
+		SetAttr:      v[35],
+		Verify:       v[36],
+		Write:        v[37],
+		RelLockOwner: v[38],
+	}
+
+	return stats, nil
+}

vendor/github.com/prometheus/procfs/nfs/parse_nfs.go

@@ -0,0 +1,67 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package nfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/prometheus/procfs/internal/util"
+)
+
+// ParseClientRPCStats returns stats read from /proc/net/rpc/nfs
+func ParseClientRPCStats(r io.Reader) (*ClientRPCStats, error) {
+	stats := &ClientRPCStats{}
+
+	scanner := bufio.NewScanner(r)
+	for scanner.Scan() {
+		line := scanner.Text()
+		parts := strings.Fields(scanner.Text())
+		// require at least <key> <value>
+		if len(parts) < 2 {
+			return nil, fmt.Errorf("invalid NFS metric line %q", line)
+		}
+
+		values, err := util.ParseUint64s(parts[1:])
+		if err != nil {
+			return nil, fmt.Errorf("error parsing NFS metric line: %s", err)
+		}
+
+		switch metricLine := parts[0]; metricLine {
+		case "net":
+			stats.Network, err = parseNetwork(values)
+		case "rpc":
+			stats.ClientRPC, err = parseClientRPC(values)
+		case "proc2":
+			stats.V2Stats, err = parseV2Stats(values)
+		case "proc3":
+			stats.V3Stats, err = parseV3Stats(values)
+		case "proc4":
+			stats.ClientV4Stats, err = parseClientV4Stats(values)
+		default:
+			return nil, fmt.Errorf("unknown NFS metric line %q", metricLine)
+		}
+		if err != nil {
+			return nil, fmt.Errorf("errors parsing NFS metric line: %s", err)
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("error scanning NFS file: %s", err)
+	}
+
+	return stats, nil
+}

vendor/github.com/prometheus/procfs/nfs/parse_nfsd.go

@@ -0,0 +1,89 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package nfs
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"strings"
+
+	"github.com/prometheus/procfs/internal/util"
+)
+
+// ParseServerRPCStats returns stats read from /proc/net/rpc/nfsd
+func ParseServerRPCStats(r io.Reader) (*ServerRPCStats, error) {
+	stats := &ServerRPCStats{}
+
+	scanner := bufio.NewScanner(r)
+	for scanner.Scan() {
+		line := scanner.Text()
+		parts := strings.Fields(scanner.Text())
+		// require at least <key> <value>
+		if len(parts) < 2 {
+			return nil, fmt.Errorf("invalid NFSd metric line %q", line)
+		}
+		label := parts[0]
+
+		var values []uint64
+		var err error
+		if label == "th" {
+			if len(parts) < 3 {
+				return nil, fmt.Errorf("invalid NFSd th metric line %q", line)
+			}
+			values, err = util.ParseUint64s(parts[1:3])
+		} else {
+			values, err = util.ParseUint64s(parts[1:])
+		}
+		if err != nil {
+			return nil, fmt.Errorf("error parsing NFSd metric line: %s", err)
+		}
+
+		switch metricLine := parts[0]; metricLine {
+		case "rc":
+			stats.ReplyCache, err = parseReplyCache(values)
+		case "fh":
+			stats.FileHandles, err = parseFileHandles(values)
+		case "io":
+			stats.InputOutput, err = parseInputOutput(values)
+		case "th":
+			stats.Threads, err = parseThreads(values)
+		case "ra":
+			stats.ReadAheadCache, err = parseReadAheadCache(values)
+		case "net":
+			stats.Network, err = parseNetwork(values)
+		case "rpc":
+			stats.ServerRPC, err = parseServerRPC(values)
+		case "proc2":
+			stats.V2Stats, err = parseV2Stats(values)
+		case "proc3":
+			stats.V3Stats, err = parseV3Stats(values)
+		case "proc4":
+			stats.ServerV4Stats, err = parseServerV4Stats(values)
+		case "proc4ops":
+			stats.V4Ops, err = parseV4Ops(values)
+		default:
+			return nil, fmt.Errorf("unknown NFSd metric line %q", metricLine)
+		}
+		if err != nil {
+			return nil, fmt.Errorf("errors parsing NFSd metric line: %s", err)
+		}
+	}
+
+	if err := scanner.Err(); err != nil {
+		return nil, fmt.Errorf("error scanning NFSd file: %s", err)
+	}
+
+	return stats, nil
+}

vendor/github.com/prometheus/procfs/proc.go

@@ -0,0 +1,238 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// Proc provides information about a running process.
+type Proc struct {
+	// The process ID.
+	PID int
+
+	fs FS
+}
+
+// Procs represents a list of Proc structs.
+type Procs []Proc
+
+func (p Procs) Len() int           { return len(p) }
+func (p Procs) Swap(i, j int)      { p[i], p[j] = p[j], p[i] }
+func (p Procs) Less(i, j int) bool { return p[i].PID < p[j].PID }
+
+// Self returns a process for the current process read via /proc/self.
+func Self() (Proc, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return Proc{}, err
+	}
+	return fs.Self()
+}
+
+// NewProc returns a process for the given pid under /proc.
+func NewProc(pid int) (Proc, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return Proc{}, err
+	}
+	return fs.NewProc(pid)
+}
+
+// AllProcs returns a list of all currently available processes under /proc.
+func AllProcs() (Procs, error) {
+	fs, err := NewFS(DefaultMountPoint)
+	if err != nil {
+		return Procs{}, err
+	}
+	return fs.AllProcs()
+}
+
+// Self returns a process for the current process.
+func (fs FS) Self() (Proc, error) {
+	p, err := os.Readlink(fs.Path("self"))
+	if err != nil {
+		return Proc{}, err
+	}
+	pid, err := strconv.Atoi(strings.Replace(p, string(fs), "", -1))
+	if err != nil {
+		return Proc{}, err
+	}
+	return fs.NewProc(pid)
+}
+
+// NewProc returns a process for the given pid.
+func (fs FS) NewProc(pid int) (Proc, error) {
+	if _, err := os.Stat(fs.Path(strconv.Itoa(pid))); err != nil {
+		return Proc{}, err
+	}
+	return Proc{PID: pid, fs: fs}, nil
+}
+
+// AllProcs returns a list of all currently available processes.
+func (fs FS) AllProcs() (Procs, error) {
+	d, err := os.Open(fs.Path())
+	if err != nil {
+		return Procs{}, err
+	}
+	defer d.Close()
+
+	names, err := d.Readdirnames(-1)
+	if err != nil {
+		return Procs{}, fmt.Errorf("could not read %s: %s", d.Name(), err)
+	}
+
+	p := Procs{}
+	for _, n := range names {
+		pid, err := strconv.ParseInt(n, 10, 64)
+		if err != nil {
+			continue
+		}
+		p = append(p, Proc{PID: int(pid), fs: fs})
+	}
+
+	return p, nil
+}
+
+// CmdLine returns the command line of a process.
+func (p Proc) CmdLine() ([]string, error) {
+	f, err := os.Open(p.path("cmdline"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	data, err := ioutil.ReadAll(f)
+	if err != nil {
+		return nil, err
+	}
+
+	if len(data) < 1 {
+		return []string{}, nil
+	}
+
+	return strings.Split(string(bytes.TrimRight(data, string("\x00"))), string(byte(0))), nil
+}
+
+// Comm returns the command name of a process.
+func (p Proc) Comm() (string, error) {
+	f, err := os.Open(p.path("comm"))
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	data, err := ioutil.ReadAll(f)
+	if err != nil {
+		return "", err
+	}
+
+	return strings.TrimSpace(string(data)), nil
+}
+
+// Executable returns the absolute path of the executable command of a process.
+func (p Proc) Executable() (string, error) {
+	exe, err := os.Readlink(p.path("exe"))
+	if os.IsNotExist(err) {
+		return "", nil
+	}
+
+	return exe, err
+}
+
+// FileDescriptors returns the currently open file descriptors of a process.
+func (p Proc) FileDescriptors() ([]uintptr, error) {
+	names, err := p.fileDescriptors()
+	if err != nil {
+		return nil, err
+	}
+
+	fds := make([]uintptr, len(names))
+	for i, n := range names {
+		fd, err := strconv.ParseInt(n, 10, 32)
+		if err != nil {
+			return nil, fmt.Errorf("could not parse fd %s: %s", n, err)
+		}
+		fds[i] = uintptr(fd)
+	}
+
+	return fds, nil
+}
+
+// FileDescriptorTargets returns the targets of all file descriptors of a process.
+// If a file descriptor is not a symlink to a file (like a socket), that value will be the empty string.
+func (p Proc) FileDescriptorTargets() ([]string, error) {
+	names, err := p.fileDescriptors()
+	if err != nil {
+		return nil, err
+	}
+
+	targets := make([]string, len(names))
+
+	for i, name := range names {
+		target, err := os.Readlink(p.path("fd", name))
+		if err == nil {
+			targets[i] = target
+		}
+	}
+
+	return targets, nil
+}
+
+// FileDescriptorsLen returns the number of currently open file descriptors of
+// a process.
+func (p Proc) FileDescriptorsLen() (int, error) {
+	fds, err := p.fileDescriptors()
+	if err != nil {
+		return 0, err
+	}
+
+	return len(fds), nil
+}
+
+// MountStats retrieves statistics and configuration for mount points in a
+// process's namespace.
+func (p Proc) MountStats() ([]*Mount, error) {
+	f, err := os.Open(p.path("mountstats"))
+	if err != nil {
+		return nil, err
+	}
+	defer f.Close()
+
+	return parseMountStats(f)
+}
+
+func (p Proc) fileDescriptors() ([]string, error) {
+	d, err := os.Open(p.path("fd"))
+	if err != nil {
+		return nil, err
+	}
+	defer d.Close()
+
+	names, err := d.Readdirnames(-1)
+	if err != nil {
+		return nil, fmt.Errorf("could not read %s: %s", d.Name(), err)
+	}
+
+	return names, nil
+}
+
+func (p Proc) path(pa ...string) string {
+	return p.fs.Path(append([]string{strconv.Itoa(p.PID)}, pa...)...)
+}

vendor/github.com/prometheus/procfs/proc_io.go

@@ -0,0 +1,65 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+)
+
+// ProcIO models the content of /proc/<pid>/io.
+type ProcIO struct {
+	// Chars read.
+	RChar uint64
+	// Chars written.
+	WChar uint64
+	// Read syscalls.
+	SyscR uint64
+	// Write syscalls.
+	SyscW uint64
+	// Bytes read.
+	ReadBytes uint64
+	// Bytes written.
+	WriteBytes uint64
+	// Bytes written, but taking into account truncation. See
+	// Documentation/filesystems/proc.txt in the kernel sources for
+	// detailed explanation.
+	CancelledWriteBytes int64
+}
+
+// NewIO creates a new ProcIO instance from a given Proc instance.
+func (p Proc) NewIO() (ProcIO, error) {
+	pio := ProcIO{}
+
+	f, err := os.Open(p.path("io"))
+	if err != nil {
+		return pio, err
+	}
+	defer f.Close()
+
+	data, err := ioutil.ReadAll(f)
+	if err != nil {
+		return pio, err
+	}
+
+	ioFormat := "rchar: %d\nwchar: %d\nsyscr: %d\nsyscw: %d\n" +
+		"read_bytes: %d\nwrite_bytes: %d\n" +
+		"cancelled_write_bytes: %d\n"
+
+	_, err = fmt.Sscanf(string(data), ioFormat, &pio.RChar, &pio.WChar, &pio.SyscR,
+		&pio.SyscW, &pio.ReadBytes, &pio.WriteBytes, &pio.CancelledWriteBytes)
+
+	return pio, err
+}

vendor/github.com/prometheus/procfs/proc_limits.go

@@ -0,0 +1,150 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"fmt"
+	"os"
+	"regexp"
+	"strconv"
+)
+
+// ProcLimits represents the soft limits for each of the process's resource
+// limits. For more information see getrlimit(2):
+// http://man7.org/linux/man-pages/man2/getrlimit.2.html.
+type ProcLimits struct {
+	// CPU time limit in seconds.
+	CPUTime int64
+	// Maximum size of files that the process may create.
+	FileSize int64
+	// Maximum size of the process's data segment (initialized data,
+	// uninitialized data, and heap).
+	DataSize int64
+	// Maximum size of the process stack in bytes.
+	StackSize int64
+	// Maximum size of a core file.
+	CoreFileSize int64
+	// Limit of the process's resident set in pages.
+	ResidentSet int64
+	// Maximum number of processes that can be created for the real user ID of
+	// the calling process.
+	Processes int64
+	// Value one greater than the maximum file descriptor number that can be
+	// opened by this process.
+	OpenFiles int64
+	// Maximum number of bytes of memory that may be locked into RAM.
+	LockedMemory int64
+	// Maximum size of the process's virtual memory address space in bytes.
+	AddressSpace int64
+	// Limit on the combined number of flock(2) locks and fcntl(2) leases that
+	// this process may establish.
+	FileLocks int64
+	// Limit of signals that may be queued for the real user ID of the calling
+	// process.
+	PendingSignals int64
+	// Limit on the number of bytes that can be allocated for POSIX message
+	// queues for the real user ID of the calling process.
+	MsqqueueSize int64
+	// Limit of the nice priority set using setpriority(2) or nice(2).
+	NicePriority int64
+	// Limit of the real-time priority set using sched_setscheduler(2) or
+	// sched_setparam(2).
+	RealtimePriority int64
+	// Limit (in microseconds) on the amount of CPU time that a process
+	// scheduled under a real-time scheduling policy may consume without making
+	// a blocking system call.
+	RealtimeTimeout int64
+}
+
+const (
+	limitsFields    = 3
+	limitsUnlimited = "unlimited"
+)
+
+var (
+	limitsDelimiter = regexp.MustCompile("  +")
+)
+
+// NewLimits returns the current soft limits of the process.
+func (p Proc) NewLimits() (ProcLimits, error) {
+	f, err := os.Open(p.path("limits"))
+	if err != nil {
+		return ProcLimits{}, err
+	}
+	defer f.Close()
+
+	var (
+		l = ProcLimits{}
+		s = bufio.NewScanner(f)
+	)
+	for s.Scan() {
+		fields := limitsDelimiter.Split(s.Text(), limitsFields)
+		if len(fields) != limitsFields {
+			return ProcLimits{}, fmt.Errorf(
+				"couldn't parse %s line %s", f.Name(), s.Text())
+		}
+
+		switch fields[0] {
+		case "Max cpu time":
+			l.CPUTime, err = parseInt(fields[1])
+		case "Max file size":
+			l.FileSize, err = parseInt(fields[1])
+		case "Max data size":
+			l.DataSize, err = parseInt(fields[1])
+		case "Max stack size":
+			l.StackSize, err = parseInt(fields[1])
+		case "Max core file size":
+			l.CoreFileSize, err = parseInt(fields[1])
+		case "Max resident set":
+			l.ResidentSet, err = parseInt(fields[1])
+		case "Max processes":
+			l.Processes, err = parseInt(fields[1])
+		case "Max open files":
+			l.OpenFiles, err = parseInt(fields[1])
+		case "Max locked memory":
+			l.LockedMemory, err = parseInt(fields[1])
+		case "Max address space":
+			l.AddressSpace, err = parseInt(fields[1])
+		case "Max file locks":
+			l.FileLocks, err = parseInt(fields[1])
+		case "Max pending signals":
+			l.PendingSignals, err = parseInt(fields[1])
+		case "Max msgqueue size":
+			l.MsqqueueSize, err = parseInt(fields[1])
+		case "Max nice priority":
+			l.NicePriority, err = parseInt(fields[1])
+		case "Max realtime priority":
+			l.RealtimePriority, err = parseInt(fields[1])
+		case "Max realtime timeout":
+			l.RealtimeTimeout, err = parseInt(fields[1])
+		}
+		if err != nil {
+			return ProcLimits{}, err
+		}
+	}
+
+	return l, s.Err()
+}
+
+func parseInt(s string) (int64, error) {
+	if s == limitsUnlimited {
+		return -1, nil
+	}
+	i, err := strconv.ParseInt(s, 10, 64)
+	if err != nil {
+		return 0, fmt.Errorf("couldn't parse value %s: %s", s, err)
+	}
+	return i, nil
+}

vendor/github.com/prometheus/procfs/proc_ns.go

@@ -0,0 +1,68 @@
+// Copyright 2018 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+)
+
+// Namespace represents a single namespace of a process.
+type Namespace struct {
+	Type  string // Namespace type.
+	Inode uint32 // Inode number of the namespace. If two processes are in the same namespace their inodes will match.
+}
+
+// Namespaces contains all of the namespaces that the process is contained in.
+type Namespaces map[string]Namespace
+
+// NewNamespaces reads from /proc/[pid/ns/* to get the namespaces of which the
+// process is a member.
+func (p Proc) NewNamespaces() (Namespaces, error) {
+	d, err := os.Open(p.path("ns"))
+	if err != nil {
+		return nil, err
+	}
+	defer d.Close()
+
+	names, err := d.Readdirnames(-1)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read contents of ns dir: %v", err)
+	}
+
+	ns := make(Namespaces, len(names))
+	for _, name := range names {
+		target, err := os.Readlink(p.path("ns", name))
+		if err != nil {
+			return nil, err
+		}
+
+		fields := strings.SplitN(target, ":", 2)
+		if len(fields) != 2 {
+			return nil, fmt.Errorf("failed to parse namespace type and inode from '%v'", target)
+		}
+
+		typ := fields[0]
+		inode, err := strconv.ParseUint(strings.Trim(fields[1], "[]"), 10, 32)
+		if err != nil {
+			return nil, fmt.Errorf("failed to parse inode from '%v': %v", fields[1], err)
+		}
+
+		ns[name] = Namespace{typ, uint32(inode)}
+	}
+
+	return ns, nil
+}