Do not serve controller requests until init is done.

controller/JSONDB.cpp

@@ -26,7 +26,8 @@ static const nlohmann::json _EMPTY_JSON(nlohmann::json::object());
 static const std::map<std::string,std::string> _ZT_JSONDB_GET_HEADERS;
 
 JSONDB::JSONDB(const std::string &basePath) :
-	_basePath(basePath)
+	_basePath(basePath),
+	_ready(false)
 {
 	if ((_basePath.length() > 7)&&(_basePath.substr(0,7) == "http://")) {
 		// TODO: this doesn't yet support IPv6 since bracketed address notiation isn't supported.
@@ -49,7 +50,7 @@ JSONDB::JSONDB(const std::string &basePath) :
 		OSUtils::mkdir(_basePath.c_str());
 		OSUtils::lockDownFile(_basePath.c_str(),true); // networks might contain auth tokens, etc., so restrict directory permissions
 	}
-	_reload(_basePath,std::string());
+	_ready = _reload(_basePath,std::string());
 }
 
 bool JSONDB::writeRaw(const std::string &n,const std::string &obj)
@@ -83,9 +84,13 @@ bool JSONDB::put(const std::string &n,const nlohmann::json &obj)
 
 const nlohmann::json &JSONDB::get(const std::string &n)
 {
+	while (!_ready) {
+		Thread::sleep(250);
+		_ready = _reload(_basePath,std::string());
+	}
+
 	if (!_isValidObjectName(n))
 		return _EMPTY_JSON;
-
 	std::map<std::string,_E>::iterator e(_db.find(n));
 	if (e != _db.end())
 		return e->second.obj;
@@ -133,7 +138,7 @@ void JSONDB::erase(const std::string &n)
 	_db.erase(n);
 }
 
-void JSONDB::_reload(const std::string &p,const std::string &b)
+bool JSONDB::_reload(const std::string &p,const std::string &b)
 {
 	if (_httpAddr) {
 		std::string body;
@@ -150,11 +155,11 @@ void JSONDB::_reload(const std::string &p,const std::string &b)
 							_db[tmp].obj = i.value();
 						}
 					}
+					return true;
 				}
-			} catch ( ... ) {
-				// TODO: report error?
-			}
+			} catch ( ... ) {} // invalid JSON, so maybe incomplete request
 		}
+		return false;
 	} else {
 		std::vector<std::string> dl(OSUtils::listDirectory(p.c_str(),true));
 		for(std::vector<std::string>::const_iterator di(dl.begin());di!=dl.end();++di) {
@@ -164,6 +169,7 @@ void JSONDB::_reload(const std::string &p,const std::string &b)
 				this->_reload((p + ZT_PATH_SEPARATOR + *di),(b + *di + ZT_PATH_SEPARATOR));
 			}
 		}
+		return true;
 	}
 }
 

controller/JSONDB.hpp

@@ -36,6 +36,7 @@
 #include "../ext/json/json.hpp"
 #include "../osdep/OSUtils.hpp"
 #include "../osdep/Http.hpp"
+#include "../osdep/Thread.hpp"
 
 namespace ZeroTier {
 
@@ -47,12 +48,6 @@ class JSONDB
 public:
 	JSONDB(const std::string &basePath);
 
-	inline void reload()
-	{
-		_db.clear();
-		_reload(_basePath,std::string());
-	}
-
 	bool writeRaw(const std::string &n,const std::string &obj);
 
 	bool put(const std::string &n,const nlohmann::json &obj);
@@ -79,6 +74,11 @@ public:
 	template<typename F>
 	inline void filter(const std::string &prefix,F func)
 	{
+		while (!_ready) {
+			Thread::sleep(250);
+			_ready = _reload(_basePath,std::string());
+		}
+
 		for(std::map<std::string,_E>::iterator i(_db.lower_bound(prefix));i!=_db.end();) {
 			if ((i->first.length() >= prefix.length())&&(!memcmp(i->first.data(),prefix.data(),prefix.length()))) {
 				if (!func(i->first,get(i->first))) {
@@ -94,7 +94,7 @@ public:
 	inline bool operator!=(const JSONDB &db) const { return (!(*this == db)); }
 
 private:
-	void _reload(const std::string &p,const std::string &b);
+	bool _reload(const std::string &p,const std::string &b);
 	bool _isValidObjectName(const std::string &n);
 	std::string _genPath(const std::string &n,bool create);
 
@@ -108,6 +108,7 @@ private:
 	InetAddress _httpAddr;
 	std::string _basePath;
 	std::map<std::string,_E> _db;
+	volatile bool _ready;
 };
 
 } // namespace ZeroTier