add new core and crawsl statemachine manager

archivebox/actors/actor.py

@@ -44,16 +44,17 @@ class ActorType(ABC, Generic[ModelType]):
     launch_kwargs: LaunchKwargs = {}
     mode: Literal['thread', 'process'] = 'process'
     
+    MAX_CONCURRENT_ACTORS: ClassVar[int] = min(max(2, int(cpu_count() * 0.6)), 8)   # min 2, max 8, up to 60% of available cpu cores
+    MAX_TICK_TIME: ClassVar[int] = 60                          # maximum duration in seconds to process a single object
+    
     QUERYSET: ClassVar[QuerySet]                      # the QuerySet to claim objects from
     CLAIM_WHERE: ClassVar[str] = 'status = "queued"'  # the WHERE clause to filter the objects when atomically getting the next object from the queue
     CLAIM_SET: ClassVar[str] = 'status = "started"'   # the SET clause to claim the object when atomically getting the next object from the queue
     CLAIM_ORDER: ClassVar[str] = 'created_at DESC'    # the ORDER BY clause to sort the objects with when atomically getting the next object from the queue
-    CLAIM_FROM_TOP: ClassVar[int] = 50                # the number of objects to consider when atomically getting the next object from the queue
+    CLAIM_FROM_TOP: ClassVar[int] = MAX_CONCURRENT_ACTORS * 10  # the number of objects to consider when atomically getting the next object from the queue
     ATOMIC: ClassVar[bool] = True                     # whether to atomically fetch+claim the nextobject in one step, or fetch and lock it in two steps
     
     # model_type: Type[ModelType]
-    MAX_CONCURRENT_ACTORS: ClassVar[int] = min(max(2, int(cpu_count() * 0.6)), 8)   # min 2, max 8, up to 60% of available cpu cores
-    MAX_TICK_TIME: ClassVar[int] = 60                          # maximum duration in seconds to process a single object
     
     _SPAWNED_ACTOR_PIDS: ClassVar[list[psutil.Process]] = []   # record all the pids of Actors spawned by this class
     
@@ -89,18 +90,19 @@ class ActorType(ABC, Generic[ModelType]):
     @classmethod
     def get_actors_to_spawn(cls, queue: QuerySet, running_actors: list[int]) -> list[LaunchKwargs]:
         """Get a list of launch kwargs for the number of actors to spawn based on the queue and currently running actors"""
+        queue_length = queue.count()
+        if not queue_length:                                      # queue is empty, spawn 0 actors
+            return []
+        
         actors_to_spawn: list[LaunchKwargs] = []
         max_spawnable = cls.MAX_CONCURRENT_ACTORS - len(running_actors)
-        queue_length = queue.count()
         
         # spawning new actors is expensive, avoid spawning all the actors at once. To stagger them,
         # let the next orchestrator tick handle starting another 2 on the next tick()
         # if queue_length > 10:                                   # queue is long, spawn as many as possible
         #   actors_to_spawn += max_spawnable * [{}]
         
-        if not queue_length:                                      # queue is empty, spawn 0 actors
-            return actors_to_spawn
-        elif queue_length > 4:                                    # queue is medium, spawn 1 or 2 actors
+        if queue_length > 4:                                    # queue is medium, spawn 1 or 2 actors
             actors_to_spawn += min(2, max_spawnable) * [{**cls.launch_kwargs}]
         else:                                                     # queue is short, spawn 1 actor
             actors_to_spawn += min(1, max_spawnable) * [{**cls.launch_kwargs}]
@@ -144,7 +146,6 @@ class ActorType(ABC, Generic[ModelType]):
         # return ArchiveResult.objects.filter(status='queued', extractor__in=('pdf', 'dom', 'screenshot'))
         return cls.QUERYSET
     
-    
     ### Instance Methods: Called by Actor after it has been spawned (i.e. forked as a thread or process)
     
     def runloop(self):

archivebox/actors/actor_crawl.py

@@ -1,286 +0,0 @@
-__package__ = 'archivebox.actors'
-
-import os
-import time
-from typing import ClassVar, Generic, cast, Literal, Type
-from django.utils.functional import classproperty
-
-from rich import print
-import psutil
-
-from django import db
-from django.db.models import QuerySet
-from multiprocessing import Process, cpu_count
-from threading import Thread, get_native_id
-
-from crawls.models import Crawl
-
-from .actor import ActorType, LaunchKwargs
-
-class CrawlActor(ActorType[Crawl]):
-    
-    QUERYSET: ClassVar[QuerySet] = Crawl.objects.filter(status='queued')
-    CLAIM_WHERE: ClassVar[str] = 'status = "queued"'  # the WHERE clause to filter the objects when atomically getting the next object from the queue
-    CLAIM_SET: ClassVar[str] = 'status = "started"'   # the SET clause to claim the object when atomically getting the next object from the queue
-    CLAIM_ORDER: ClassVar[str] = 'created_at DESC'    # the ORDER BY clause to sort the objects with when atomically getting the next object from the queue
-    CLAIM_FROM_TOP: ClassVar[int] = 50                # the number of objects to consider when atomically getting the next object from the queue
-    
-    # model_type: Type[ModelType]
-    MAX_CONCURRENT_ACTORS: ClassVar[int] = min(max(2, int(cpu_count() * 0.6)), 8)   # min 2, max 8, up to 60% of available cpu cores
-    MAX_TICK_TIME: ClassVar[int] = 60                          # maximum duration in seconds to process a single object
-    
-    _SPAWNED_ACTOR_PIDS: ClassVar[list[psutil.Process]] = []   # record all the pids of Actors spawned by this class
-    
-    def __init__(self, mode: Literal['thread', 'process']|None=None, **launch_kwargs: LaunchKwargs):
-        self.mode = mode or self.mode
-        self.launch_kwargs = launch_kwargs or dict(self.launch_kwargs)
-    
-    @classproperty
-    def name(cls) -> str:
-        return cls.__name__  # type: ignore
-    
-    def __str__(self) -> str:
-        return self.__repr__()
-    
-    def __repr__(self) -> str:
-        """FaviconActor[pid=1234]"""
-        label = 'pid' if self.mode == 'process' else 'tid'
-        return f'[underline]{self.name}[/underline]\\[{label}={self.pid}]'
-    
-    ### Class Methods: Called by Orchestrator on ActorType class before it has been spawned
-    
-    @classmethod
-    def get_running_actors(cls) -> list[int]:
-        """returns a list of pids of all running actors of this type"""
-        # WARNING: only works for process actors, not thread actors
-        if cls.mode == 'thread':
-            raise NotImplementedError('get_running_actors() is not implemented for thread actors')
-        return [
-            proc.pid for proc in cls._SPAWNED_ACTOR_PIDS
-            if proc.is_running() and proc.status() != 'zombie'
-        ]
-        
-    @classmethod
-    def get_actors_to_spawn(cls, queue: QuerySet, running_actors: list[int]) -> list[LaunchKwargs]:
-        """Get a list of launch kwargs for the number of actors to spawn based on the queue and currently running actors"""
-        actors_to_spawn: list[LaunchKwargs] = []
-        max_spawnable = cls.MAX_CONCURRENT_ACTORS - len(running_actors)
-        queue_length = queue.count()
-        
-        # spawning new actors is expensive, avoid spawning all the actors at once. To stagger them,
-        # let the next orchestrator tick handle starting another 2 on the next tick()
-        # if queue_length > 10:                                   # queue is long, spawn as many as possible
-        #   actors_to_spawn += max_spawnable * [{}]
-        
-        if not queue_length:                                      # queue is empty, spawn 0 actors
-            return actors_to_spawn
-        elif queue_length > 4:                                    # queue is medium, spawn 1 or 2 actors
-            actors_to_spawn += min(2, max_spawnable) * [{**cls.launch_kwargs}]
-        else:                                                     # queue is short, spawn 1 actor
-            actors_to_spawn += min(1, max_spawnable) * [{**cls.launch_kwargs}]
-        return actors_to_spawn
-        
-    @classmethod
-    def start(cls, mode: Literal['thread', 'process']='process', **launch_kwargs: LaunchKwargs) -> int:
-        if mode == 'thread':
-            return cls.fork_actor_as_thread(**launch_kwargs)
-        elif mode == 'process':
-            return cls.fork_actor_as_process(**launch_kwargs)
-        raise ValueError(f'Invalid actor mode: {mode} must be "thread" or "process"')
-        
-    @classmethod
-    def fork_actor_as_thread(cls, **launch_kwargs: LaunchKwargs) -> int:
-        """Spawn a new background thread running the actor's runloop"""
-        actor = cls(mode='thread', **launch_kwargs)
-        bg_actor_thread = Thread(target=actor.runloop)
-        bg_actor_thread.start()
-        assert bg_actor_thread.native_id is not None
-        return bg_actor_thread.native_id
-    
-    @classmethod
-    def fork_actor_as_process(cls, **launch_kwargs: LaunchKwargs) -> int:
-        """Spawn a new background process running the actor's runloop"""
-        actor = cls(mode='process', **launch_kwargs)
-        bg_actor_process = Process(target=actor.runloop)
-        bg_actor_process.start()
-        assert bg_actor_process.pid is not None
-        cls._SPAWNED_ACTOR_PIDS.append(psutil.Process(pid=bg_actor_process.pid))
-        return bg_actor_process.pid
-    
-    @classmethod
-    def get_model(cls) -> Type[ModelType]:
-        # wish this was a @classproperty but Generic[ModelType] return type cant be statically inferred for @classproperty
-        return cls.QUERYSET.model
-    
-    @classmethod
-    def get_queue(cls) -> QuerySet:
-        """override this to provide your queryset as the queue"""
-        # return ArchiveResult.objects.filter(status='queued', extractor__in=('pdf', 'dom', 'screenshot'))
-        return cls.QUERYSET
-    
-    
-    ### Instance Methods: Called by Actor after it has been spawned (i.e. forked as a thread or process)
-    
-    def runloop(self):
-        """The main runloop that starts running when the actor is spawned (as subprocess or thread) and exits when the queue is empty"""
-        self.on_startup()
-        try:
-            while True:
-                obj_to_process: ModelType | None = None
-                try:
-                    obj_to_process = cast(ModelType, self.get_next(atomic=self.atomic))
-                except Exception:
-                    pass
-                
-                if obj_to_process:
-                    self.idle_count = 0   # reset idle count if we got an object
-                else:
-                    if self.idle_count >= 30:
-                        break             # stop looping and exit if queue is empty and we have idled for 30sec
-                    else:
-                        # print('Actor runloop()', f'pid={self.pid}', 'queue empty, rechecking...')
-                        self.idle_count += 1
-                        time.sleep(1)
-                        continue
-                
-                self.on_tick_start(obj_to_process)
-                
-                # Process the object
-                try:
-                    self.tick(obj_to_process)
-                except Exception as err:
-                    print(f'[red]🏃‍♂️ ERROR: {self}.tick()[/red]', err)
-                    db.connections.close_all()                         # always reset the db connection after an exception to clear any pending transactions
-                    self.on_tick_exception(obj_to_process, err)
-                finally:
-                    self.on_tick_end(obj_to_process)
-            
-            self.on_shutdown(err=None)
-        except BaseException as err:
-            if isinstance(err, KeyboardInterrupt):
-                print()
-            else:
-                print(f'\n[red]🏃‍♂️ {self}.runloop() FATAL:[/red]', err.__class__.__name__, err)
-            self.on_shutdown(err=err)
-    
-    def get_next(self, atomic: bool | None=None) -> ModelType | None:
-        """get the next object from the queue, atomically locking it if self.atomic=True"""
-        if atomic is None:
-            atomic = self.ATOMIC
-
-        if atomic:
-            # fetch and claim the next object from in the queue in one go atomically
-            obj = self.get_next_atomic()
-        else:
-            # two-step claim: fetch the next object and lock it in a separate query
-            obj = self.get_queue().last()
-            assert obj and self.lock_next(obj), f'Unable to fetch+lock the next {self.get_model().__name__} ojbect from {self}.QUEUE'
-        return obj
-    
-    def lock_next(self, obj: ModelType) -> bool:
-        """override this to implement a custom two-step (non-atomic)lock mechanism"""
-        # For example:
-        # assert obj._model.objects.filter(pk=obj.pk, status='queued').update(status='started', locked_by=self.pid)
-        # Not needed if using get_next_and_lock() to claim the object atomically
-        # print(f'[blue]🏃‍♂️ {self}.lock()[/blue]', obj.abid or obj.id)
-        return True
-    
-    def claim_sql_where(self) -> str:
-        """override this to implement a custom WHERE clause for the atomic claim step e.g. "status = 'queued' AND locked_by = NULL" """
-        return self.CLAIM_WHERE
-    
-    def claim_sql_set(self) -> str:
-        """override this to implement a custom SET clause for the atomic claim step e.g. "status = 'started' AND locked_by = {self.pid}" """
-        return self.CLAIM_SET
-    
-    def claim_sql_order(self) -> str:
-        """override this to implement a custom ORDER BY clause for the atomic claim step e.g. "created_at DESC" """
-        return self.CLAIM_ORDER
-    
-    def claim_from_top(self) -> int:
-        """override this to implement a custom number of objects to consider when atomically claiming the next object from the top of the queue"""
-        return self.CLAIM_FROM_TOP
-        
-    def get_next_atomic(self, shallow: bool=True) -> ModelType | None:
-        """
-        claim a random object from the top n=50 objects in the queue (atomically updates status=queued->started for claimed object)
-        optimized for minimizing contention on the queue with other actors selecting from the same list
-        slightly faster than claim_any_obj() which selects randomly from the entire queue but needs to know the total count
-        """
-        Model = self.get_model()                                     # e.g. ArchiveResult
-        table = f'{Model._meta.app_label}_{Model._meta.model_name}'  # e.g. core_archiveresult
-        
-        where_sql = self.claim_sql_where()
-        set_sql = self.claim_sql_set()
-        order_by_sql = self.claim_sql_order()
-        choose_from_top = self.claim_from_top()
-        
-        with db.connection.cursor() as cursor:
-            # subquery gets the pool of the top 50 candidates sorted by sort and order
-            # main query selects a random one from that pool
-            cursor.execute(f"""
-                UPDATE {table} 
-                SET {set_sql}
-                WHERE {where_sql} and id = (
-                    SELECT id FROM (
-                        SELECT id FROM {table}
-                        WHERE {where_sql}
-                        ORDER BY {order_by_sql}
-                        LIMIT {choose_from_top}
-                    ) candidates
-                    ORDER BY RANDOM()
-                    LIMIT 1
-                )
-                RETURNING id;
-            """)
-            result = cursor.fetchone()
-            
-            if result is None:
-                return None           # If no rows were claimed, return None
-
-            if shallow:
-                # shallow: faster, returns potentially incomplete object instance missing some django auto-populated fields:
-                columns = [col[0] for col in cursor.description or ['id']]
-                return Model(**dict(zip(columns, result)))
-
-            # if not shallow do one extra query to get a more complete object instance (load it fully from scratch)
-            return Model.objects.get(id=result[0])
-
-    @abstractmethod
-    def tick(self, obj: ModelType) -> None:
-        """override this to process the object"""
-        print(f'[blue]🏃‍♂️ {self}.tick()[/blue]', obj.abid or obj.id)
-        # For example:
-        # do_some_task(obj)
-        # do_something_else(obj)
-        # obj._model.objects.filter(pk=obj.pk, status='started').update(status='success')
-        raise NotImplementedError('tick() must be implemented by the Actor subclass')
-    
-    def on_startup(self) -> None:
-        if self.mode == 'thread':
-            self.pid = get_native_id()  # thread id
-            print(f'[green]🏃‍♂️ {self}.on_startup() STARTUP (THREAD)[/green]')
-        else:
-            self.pid = os.getpid()      # process id
-            print(f'[green]🏃‍♂️ {self}.on_startup() STARTUP (PROCESS)[/green]')
-        # abx.pm.hook.on_actor_startup(self)
-        
-    def on_shutdown(self, err: BaseException | None=None) -> None:
-        print(f'[grey53]🏃‍♂️ {self}.on_shutdown() SHUTTING DOWN[/grey53]', err or '[green](gracefully)[/green]')
-        # abx.pm.hook.on_actor_shutdown(self)
-        
-    def on_tick_start(self, obj: ModelType) -> None:
-        # print(f'🏃‍♂️ {self}.on_tick_start()', obj.abid or obj.id)
-        # abx.pm.hook.on_actor_tick_start(self, obj_to_process)
-        # self.timer = TimedProgress(self.MAX_TICK_TIME, prefix='      ')
-        pass
-    
-    def on_tick_end(self, obj: ModelType) -> None:
-        # print(f'🏃‍♂️ {self}.on_tick_end()', obj.abid or obj.id)
-        # abx.pm.hook.on_actor_tick_end(self, obj_to_process)
-        # self.timer.end()
-        pass
-    
-    def on_tick_exception(self, obj: ModelType, err: BaseException) -> None:
-        print(f'[red]🏃‍♂️ {self}.on_tick_exception()[/red]', obj.abid or obj.id, err)
-        # abx.pm.hook.on_actor_tick_exception(self, obj_to_process, err)

archivebox/actors/orchestrator.py

@@ -3,8 +3,7 @@ __package__ = 'archivebox.actors'
 import os
 import time
 import itertools
-import uuid
-from typing import Dict, Type, Literal
+from typing import Dict, Type, Literal, ClassVar
 from django.utils.functional import classproperty
 
 from multiprocessing import Process, cpu_count
@@ -173,54 +172,36 @@ from django import db
 from django.db import connection
 
 
+from crawls.actors import CrawlActor
+from .actor_snapshot import SnapshotActor
+
+from abx_plugin_singlefile.actors import SinglefileActor
 
 
 class FaviconActor(ActorType[ArchiveResult]):
-    @classmethod
-    def get_queue(cls) -> QuerySet[ArchiveResult]:
-        return ArchiveResult.objects.filter(status='failed', extractor='favicon')
-    
-    @classmethod
-    def get_next(cls) -> ArchiveResult | None:
-        # return cls.get_next_atomic(
-        #     model=ArchiveResult,
-        #     where='status = "failed"',
-        #     set='status = "started"',
-        #     order_by='created_at DESC',
-        #     choose_from_top=cpu_count() * 10,
-        # )
-        return cls.get_random(
-            model=ArchiveResult,
-            where='status = "failed" AND extractor = "favicon"',
-            set='status = "queued"',
-            choose_from_top=50,
-        )
+    CLAIM_ORDER: ClassVar[str] = 'created_at DESC'
+    CLAIM_WHERE: ClassVar[str] = 'status = "queued" AND extractor = "favicon"'
+    CLAIM_SET: ClassVar[str] = 'status = "started"'
     
+    @classproperty
+    def QUERYSET(cls) -> QuerySet:
+        return ArchiveResult.objects.filter(status='failed', extractor='favicon')
+
     def tick(self, obj: ArchiveResult):
         print(f'[grey53]{self}.tick({obj.abid or obj.id}, status={obj.status}) remaining:[/grey53]', self.get_queue().count())
         updated = ArchiveResult.objects.filter(id=obj.id, status='started').update(status='success') == 1
         if not updated:
             raise Exception(f'Failed to update {obj.abid or obj.id}, interrupted by another actor writing to the same object')
-        # obj.refresh_from_db()
-        obj.status = 'success'
-        
-    def lock(self, obj: ArchiveResult) -> bool:
-        """As an alternative to self.get_next_atomic(), we can use select_for_update() or manually update a semaphore field here"""
-
-        locked = ArchiveResult.objects.filter(id=obj.id, status='queued').update(status='started') == 1
-        if locked:
-            # obj.refresh_from_db()
-            obj.status = 'started'
-            # print(f'FaviconActor[{self.pid}] lock({obj.id}) 🔒')
-            pass
-        else:
-            print(f'FaviconActor[{self.pid}] lock({obj.id}) X')
-        return locked
+        obj.refresh_from_db()
+        obj.save()
 
 
 class ExtractorsOrchestrator(Orchestrator):
     actor_types = {
+        'CrawlActor': CrawlActor,
+        'SnapshotActor': SnapshotActor,
         'FaviconActor': FaviconActor,
+        'SinglefileActor': SinglefileActor,
     }
 
 

archivebox/actors/statemachine.py

@@ -0,0 +1,286 @@
+from statemachine import State, StateMachine
+from django.db import models
+from multiprocessing import Process
+import psutil
+import time
+
+# State Machine Definitions
+#################################################
+
+class SnapshotMachine(StateMachine):
+    """State machine for managing Snapshot lifecycle."""
+    
+    # States
+    queued = State(initial=True)
+    started = State()
+    sealed = State(final=True)
+    
+    # Transitions
+    start = queued.to(started, cond='can_start')
+    seal = started.to(sealed, cond='is_finished')
+    
+    # Events
+    tick = (
+        queued.to.itself(unless='can_start') |
+        queued.to(started, cond='can_start') |
+        started.to.itself(unless='is_finished') |
+        started.to(sealed, cond='is_finished')
+    )
+    
+    def __init__(self, snapshot):
+        self.snapshot = snapshot
+        super().__init__()
+        
+    def can_start(self):
+        return True
+        
+    def is_finished(self):
+        return not self.snapshot.has_pending_archiveresults()
+        
+    def before_start(self):
+        """Pre-start validation and setup."""
+        self.snapshot.cleanup_dir()
+        
+    def after_start(self):
+        """Post-start side effects."""
+        self.snapshot.create_pending_archiveresults()
+        self.snapshot.update_indices()
+        self.snapshot.bump_retry_at(seconds=10)
+        
+    def before_seal(self):
+        """Pre-seal validation and cleanup."""
+        self.snapshot.cleanup_dir()
+        
+    def after_seal(self):
+        """Post-seal actions."""
+        self.snapshot.update_indices()
+        self.snapshot.seal_dir()
+        self.snapshot.upload_dir()
+        self.snapshot.retry_at = None
+        self.snapshot.save()
+
+
+class ArchiveResultMachine(StateMachine):
+    """State machine for managing ArchiveResult lifecycle."""
+    
+    # States
+    queued = State(initial=True)
+    started = State()
+    succeeded = State(final=True)
+    backoff = State()
+    failed = State(final=True)
+    
+    # Transitions
+    start = queued.to(started, cond='can_start')
+    succeed = started.to(succeeded, cond='extractor_succeeded')
+    backoff = started.to(backoff, unless='extractor_succeeded')
+    retry = backoff.to(queued, cond='can_retry')
+    fail = backoff.to(failed, unless='can_retry')
+    
+    # Events
+    tick = (
+        queued.to.itself(unless='can_start') |
+        queued.to(started, cond='can_start') |
+        started.to.itself(cond='extractor_still_running') |
+        started.to(succeeded, cond='extractor_succeeded') |
+        started.to(backoff, unless='extractor_succeeded') |
+        backoff.to.itself(cond='still_waiting_to_retry') |
+        backoff.to(queued, cond='can_retry') |
+        backoff.to(failed, unless='can_retry')
+    )
+    
+    def __init__(self, archiveresult):
+        self.archiveresult = archiveresult
+        super().__init__()
+    
+    def can_start(self):
+        return True
+    
+    def extractor_still_running(self):
+        return self.archiveresult.start_ts > time.now() - timedelta(seconds=5)
+    
+    def extractor_succeeded(self):
+        # return check_if_extractor_succeeded(self.archiveresult)
+        return self.archiveresult.start_ts < time.now() - timedelta(seconds=5)
+    
+    def can_retry(self):
+        return self.archiveresult.retries < self.archiveresult.max_retries
+        
+    def before_start(self):
+        """Pre-start initialization."""
+        self.archiveresult.retries += 1
+        self.archiveresult.start_ts = time.now()
+        self.archiveresult.output = None
+        self.archiveresult.error = None
+        
+    def after_start(self):
+        """Post-start execution."""
+        self.archiveresult.bump_retry_at(seconds=self.archiveresult.timeout + 5)
+        execute_extractor(self.archiveresult)
+        self.archiveresult.snapshot.bump_retry_at(seconds=5)
+        
+    def before_succeed(self):
+        """Pre-success validation."""
+        self.archiveresult.output = get_archiveresult_output(self.archiveresult)
+        
+    def after_succeed(self):
+        """Post-success cleanup."""
+        self.archiveresult.end_ts = time.now()
+        self.archiveresult.retry_at = None
+        self.archiveresult.update_indices()
+        
+    def before_backoff(self):
+        """Pre-backoff error capture."""
+        self.archiveresult.error = get_archiveresult_error(self.archiveresult)
+        
+    def after_backoff(self):
+        """Post-backoff retry scheduling."""
+        self.archiveresult.end_ts = time.now()
+        self.archiveresult.bump_retry_at(
+            seconds=self.archiveresult.timeout * self.archiveresult.retries
+        )
+        self.archiveresult.update_indices()
+        
+    def before_fail(self):
+        """Pre-failure finalization."""
+        self.archiveresult.retry_at = None
+        
+    def after_fail(self):
+        """Post-failure cleanup."""
+        self.archiveresult.update_indices()
+
+# Models
+#################################################
+
+class Snapshot(models.Model):
+    status = models.CharField(max_length=32, default='queued')
+    retry_at = models.DateTimeField(null=True)
+    
+    @property
+    def sm(self):
+        """Get the state machine for this snapshot."""
+        return SnapshotMachine(self)
+    
+    def has_pending_archiveresults(self):
+        return self.archiveresult_set.exclude(
+            status__in=['succeeded', 'failed']
+        ).exists()
+    
+    def bump_retry_at(self, seconds):
+        self.retry_at = time.now() + timedelta(seconds=seconds)
+        self.save()
+        
+    def cleanup_dir(self):
+        cleanup_snapshot_dir(self)
+        
+    def create_pending_archiveresults(self):
+        create_snapshot_pending_archiveresults(self)
+        
+    def update_indices(self):
+        update_snapshot_index_json(self)
+        update_snapshot_index_html(self)
+        
+    def seal_dir(self):
+        seal_snapshot_dir(self)
+        
+    def upload_dir(self):
+        upload_snapshot_dir(self)
+
+
+class ArchiveResult(models.Model):
+    snapshot = models.ForeignKey(Snapshot, on_delete=models.CASCADE)
+    status = models.CharField(max_length=32, default='queued')
+    retry_at = models.DateTimeField(null=True)
+    retries = models.IntegerField(default=0)
+    max_retries = models.IntegerField(default=3)
+    timeout = models.IntegerField(default=60)
+    start_ts = models.DateTimeField(null=True)
+    end_ts = models.DateTimeField(null=True)
+    output = models.TextField(null=True)
+    error = models.TextField(null=True)
+    
+    def get_machine(self):
+        return ArchiveResultMachine(self)
+    
+    def bump_retry_at(self, seconds):
+        self.retry_at = time.now() + timedelta(seconds=seconds)
+        self.save()
+        
+    def update_indices(self):
+        update_archiveresult_index_json(self)
+        update_archiveresult_index_html(self)
+
+
+# Actor System
+#################################################
+
+class BaseActor:
+    MAX_TICK_TIME = 60
+    
+    def tick(self, obj):
+        """Process a single object through its state machine."""
+        machine = obj.get_machine()
+        
+        if machine.is_queued:
+            if machine.can_start():
+                machine.start()
+                
+        elif machine.is_started:
+            if machine.can_seal():
+                machine.seal()
+                
+        elif machine.is_backoff:
+            if machine.can_retry():
+                machine.retry()
+            else:
+                machine.fail()
+
+
+class Orchestrator:
+    """Main orchestrator that manages all actors."""
+    
+    def __init__(self):
+        self.pid = None
+        
+    @classmethod
+    def spawn(cls):
+        orchestrator = cls()
+        proc = Process(target=orchestrator.runloop)
+        proc.start()
+        return proc.pid
+        
+    def runloop(self):
+        self.pid = os.getpid()
+        abx.pm.hook.on_orchestrator_startup(self)
+        
+        try:
+            while True:
+                self.process_queue(Snapshot)
+                self.process_queue(ArchiveResult)
+                time.sleep(0.1)
+                
+        except (KeyboardInterrupt, SystemExit):
+            abx.pm.hook.on_orchestrator_shutdown(self)
+            
+    def process_queue(self, model):
+        retry_at_reached = Q(retry_at__isnull=True) | Q(retry_at__lte=time.now())
+        queue = model.objects.filter(retry_at_reached)
+        
+        if queue.exists():
+            actor = BaseActor()
+            for obj in queue:
+                try:
+                    with transaction.atomic():
+                        actor.tick(obj)
+                except Exception as e:
+                    abx.pm.hook.on_actor_tick_exception(actor, obj, e)
+
+
+# Periodic Tasks
+#################################################
+
[email protected]_task(schedule=djhuey.crontab(minute='*'))
+def ensure_orchestrator_running():
+    """Ensure orchestrator is running, start if not."""
+    if not any(p.name().startswith('Orchestrator') for p in psutil.process_iter()):
+        Orchestrator.spawn()

archivebox/core/actors.py

@@ -0,0 +1,73 @@
+__package__ = 'archivebox.core'
+
+from typing import ClassVar
+
+from rich import print
+
+from django.db.models import QuerySet
+from django.utils import timezone
+from datetime import timedelta
+from core.models import Snapshot
+
+from actors.actor import ActorType
+
+
+class SnapshotActor(ActorType[Snapshot]):
+    
+    QUERYSET: ClassVar[QuerySet] = Snapshot.objects.filter(status='queued')
+    CLAIM_WHERE: ClassVar[str] = 'status = "queued"'  # the WHERE clause to filter the objects when atomically getting the next object from the queue
+    CLAIM_SET: ClassVar[str] = 'status = "started"'   # the SET clause to claim the object when atomically getting the next object from the queue
+    CLAIM_ORDER: ClassVar[str] = 'created_at DESC'    # the ORDER BY clause to sort the objects with when atomically getting the next object from the queue
+    CLAIM_FROM_TOP: ClassVar[int] = 50                # the number of objects to consider when atomically getting the next object from the queue
+    
+    # model_type: Type[ModelType]
+    MAX_CONCURRENT_ACTORS: ClassVar[int] = 4               # min 2, max 8, up to 60% of available cpu cores
+    MAX_TICK_TIME: ClassVar[int] = 60                          # maximum duration in seconds to process a single object
+    
+    def claim_sql_where(self) -> str:
+        """override this to implement a custom WHERE clause for the atomic claim step e.g. "status = 'queued' AND locked_by = NULL" """
+        return self.CLAIM_WHERE
+    
+    def claim_sql_set(self) -> str:
+        """override this to implement a custom SET clause for the atomic claim step e.g. "status = 'started' AND locked_by = {self.pid}" """
+        retry_at = timezone.now() + timedelta(seconds=self.MAX_TICK_TIME)
+        # format as 2024-10-31 10:14:33.240903
+        retry_at_str = retry_at.strftime('%Y-%m-%d %H:%M:%S.%f')
+        return f'{self.CLAIM_SET}, retry_at = {retry_at_str}'
+    
+    def claim_sql_order(self) -> str:
+        """override this to implement a custom ORDER BY clause for the atomic claim step e.g. "created_at DESC" """
+        return self.CLAIM_ORDER
+    
+    def claim_from_top(self) -> int:
+        """override this to implement a custom number of objects to consider when atomically claiming the next object from the top of the queue"""
+        return self.CLAIM_FROM_TOP
+        
+    def tick(self, obj: Snapshot) -> None:
+        """override this to process the object"""
+        print(f'[blue]🏃‍♂️ {self}.tick()[/blue]', obj.abid or obj.id)
+        # For example:
+        # do_some_task(obj)
+        # do_something_else(obj)
+        # obj._model.objects.filter(pk=obj.pk, status='started').update(status='success')
+        # raise NotImplementedError('tick() must be implemented by the Actor subclass')
+    
+    def on_shutdown(self, err: BaseException | None=None) -> None:
+        print(f'[grey53]🏃‍♂️ {self}.on_shutdown() SHUTTING DOWN[/grey53]', err or '[green](gracefully)[/green]')
+        # abx.pm.hook.on_actor_shutdown(self)
+        
+    def on_tick_start(self, obj: Snapshot) -> None:
+        # print(f'🏃‍♂️ {self}.on_tick_start()', obj.abid or obj.id)
+        # abx.pm.hook.on_actor_tick_start(self, obj_to_process)
+        # self.timer = TimedProgress(self.MAX_TICK_TIME, prefix='      ')
+        pass
+    
+    def on_tick_end(self, obj: Snapshot) -> None:
+        # print(f'🏃‍♂️ {self}.on_tick_end()', obj.abid or obj.id)
+        # abx.pm.hook.on_actor_tick_end(self, obj_to_process)
+        # self.timer.end()
+        pass
+    
+    def on_tick_exception(self, obj: Snapshot, err: BaseException) -> None:
+        print(f'[red]🏃‍♂️ {self}.on_tick_exception()[/red]', obj.abid or obj.id, err)
+        # abx.pm.hook.on_actor_tick_exception(self, obj_to_process, err)

archivebox/core/models.py

@@ -8,21 +8,25 @@ import os
 import json
 
 from pathlib import Path
+from datetime import timedelta
 
 from django.db import models
 from django.utils.functional import cached_property
 from django.utils.text import slugify
+from django.utils import timezone
 from django.core.cache import cache
 from django.urls import reverse, reverse_lazy
 from django.db.models import Case, When, Value, IntegerField
 from django.contrib import admin
 from django.conf import settings
 
+from statemachine.mixins import MachineMixin
+
 from archivebox.config import CONSTANTS
 
 from abid_utils.models import ABIDModel, ABIDField, AutoDateTimeField
 from queues.tasks import bg_archive_snapshot
-# from crawls.models import Crawl
+from crawls.models import Crawl
 # from machine.models import Machine, NetworkInterface
 
 from archivebox.misc.system import get_dir_size
@@ -152,7 +156,7 @@ class SnapshotManager(models.Manager):
         return super().get_queryset().prefetch_related('tags', 'archiveresult_set')  # .annotate(archiveresult_count=models.Count('archiveresult')).distinct()
 
 
-class Snapshot(ABIDModel):
+class Snapshot(ABIDModel, MachineMixin):
     abid_prefix = 'snp_'
     abid_ts_src = 'self.created_at'
     abid_uri_src = 'self.url'
@@ -160,6 +164,17 @@ class Snapshot(ABIDModel):
     abid_rand_src = 'self.id'
     abid_drift_allowed = True
 
+    state_field_name = 'status'
+    state_machine_name = 'core.statemachines.SnapshotMachine'
+    state_machine_attr = 'sm'
+    
+    class SnapshotStatus(models.TextChoices):
+        QUEUED = 'queued', 'Queued'
+        STARTED = 'started', 'Started'
+        SEALED = 'sealed', 'Sealed'
+        
+    status = models.CharField(max_length=15, default=SnapshotStatus.QUEUED, null=False, blank=False)
+
     id = models.UUIDField(primary_key=True, default=None, null=False, editable=False, unique=True, verbose_name='ID')
     abid = ABIDField(prefix=abid_prefix)
 
@@ -171,7 +186,7 @@ class Snapshot(ABIDModel):
     bookmarked_at = AutoDateTimeField(default=None, null=False, editable=True, db_index=True)
     downloaded_at = models.DateTimeField(default=None, null=True, editable=False, db_index=True, blank=True)
 
-    # crawl = models.ForeignKey(Crawl, on_delete=models.CASCADE, default=None, null=True, blank=True, related_name='snapshot_set')
+    crawl = models.ForeignKey(Crawl, on_delete=models.CASCADE, default=None, null=True, blank=True, related_name='snapshot_set')
 
     url = models.URLField(unique=True, db_index=True)
     timestamp = models.CharField(max_length=32, unique=True, db_index=True, editable=False)
@@ -396,6 +411,25 @@ class Snapshot(ABIDModel):
                 tags_id.append(Tag.objects.get_or_create(name=tag)[0].pk)
         self.tags.clear()
         self.tags.add(*tags_id)
+        
+    def has_pending_archiveresults(self) -> bool:
+        pending_statuses = [ArchiveResult.ArchiveResultStatus.QUEUED, ArchiveResult.ArchiveResultStatus.STARTED]
+        pending_archiveresults = self.archiveresult_set.filter(status__in=pending_statuses)
+        return pending_archiveresults.exists()
+    
+    def create_pending_archiveresults(self) -> list['ArchiveResult']:
+        archiveresults = []
+        for extractor in EXTRACTORS:
+            archiveresult, _created = ArchiveResult.objects.get_or_create(
+                snapshot=self,
+                extractor=extractor,
+                status=ArchiveResult.ArchiveResultStatus.QUEUED,
+            )
+            archiveresults.append(archiveresult)
+        return archiveresults
+    
+    def bump_retry_at(self, seconds: int = 10):
+        self.retry_at = timezone.now() + timedelta(seconds=seconds)
 
 
     # def get_storage_dir(self, create=True, symlink=True) -> Path:
@@ -452,6 +486,20 @@ class ArchiveResult(ABIDModel):
     abid_subtype_src = 'self.extractor'
     abid_rand_src = 'self.id'
     abid_drift_allowed = True
+    
+    state_field_name = 'status'
+    state_machine_name = 'core.statemachines.ArchiveResultMachine'
+    state_machine_attr = 'sm'
+
+    class ArchiveResultStatus(models.TextChoices):
+        QUEUED = 'queued', 'Queued'
+        STARTED = 'started', 'Started'
+        SUCCEEDED = 'succeeded', 'Succeeded'
+        FAILED = 'failed', 'Failed'
+        SKIPPED = 'skipped', 'Skipped'
+        BACKOFF = 'backoff', 'Waiting to retry'
+        
+    status = models.CharField(max_length=15, choices=ArchiveResultStatus.choices, default=ArchiveResultStatus.QUEUED, null=False, blank=False)
 
     EXTRACTOR_CHOICES = (
         ('htmltotext', 'htmltotext'),
@@ -469,11 +517,7 @@ class ArchiveResult(ABIDModel):
         ('title', 'title'),
         ('wget', 'wget'),
     )
-    STATUS_CHOICES = [
-        ("succeeded", "succeeded"),
-        ("failed", "failed"),
-        ("skipped", "skipped")
-    ]
+
 
     id = models.UUIDField(primary_key=True, default=None, null=False, editable=False, unique=True, verbose_name='ID')
     abid = ABIDField(prefix=abid_prefix)
@@ -491,7 +535,6 @@ class ArchiveResult(ABIDModel):
     output = models.CharField(max_length=1024)
     start_ts = models.DateTimeField(db_index=True)
     end_ts = models.DateTimeField()
-    status = models.CharField(max_length=16, choices=STATUS_CHOICES)
 
     # the network interface that was used to download this result
     # uplink = models.ForeignKey(NetworkInterface, on_delete=models.SET_NULL, null=True, blank=True, verbose_name='Network Interface Used')
@@ -552,7 +595,15 @@ class ArchiveResult(ABIDModel):
         return link.canonical_outputs().get(f'{self.extractor}_path')
 
     def output_exists(self) -> bool:
-        return os.access(self.output_path(), os.R_OK)
+        return os.path.exists(self.output_path())
+    
+    def bump_retry_at(self, seconds: int = 10):
+        self.retry_at = timezone.now() + timedelta(seconds=seconds)
+        
+    def create_output_dir(self):
+        snap_dir = self.snapshot_dir
+        snap_dir.mkdir(parents=True, exist_ok=True)
+        return snap_dir / self.output_path()
 
 
     # def get_storage_dir(self, create=True, symlink=True):

archivebox/core/settings.py

@@ -64,7 +64,8 @@ INSTALLED_APPS = [
     # 'abid_utils',                # handles ABID ID creation, handling, and models
     'config',                    # ArchiveBox config settings (loaded as a plugin, don't need to add it here) 
     'machine',                   # handles collecting and storing information about the host machine, network interfaces, installed binaries, etc.
-    'queues',                    # handles starting and managing background workers and processes
+    'actors',                    # handles starting and managing background workers and processes (orchestrators and actors)
+    'queues',                    # handles starting and managing background workers and processes (supervisord)
     'seeds',                     # handles Seed model and URL source management
     'crawls',                    # handles Crawl and CrawlSchedule models and management
     'personas',                  # handles Persona and session management

archivebox/core/statemachines.py

@@ -0,0 +1,115 @@
+__package__ = 'archivebox.snapshots'
+
+from django.utils import timezone
+
+from statemachine import State, StateMachine
+
+from core.models import Snapshot, ArchiveResult
+
+# State Machine Definitions
+#################################################
+
+
+class SnapshotMachine(StateMachine, strict_states=True):
+    """State machine for managing Snapshot lifecycle."""
+    
+    model: Snapshot
+    
+    # States
+    queued = State(value=Snapshot.SnapshotStatus.QUEUED, initial=True)
+    started = State(value=Snapshot.SnapshotStatus.STARTED)
+    sealed = State(value=Snapshot.SnapshotStatus.SEALED, final=True)
+    
+    # Tick Event
+    tick = (
+        queued.to.itself(unless='can_start', internal=True) |
+        queued.to(started, cond='can_start') |
+        started.to.itself(unless='is_finished', internal=True) |
+        started.to(sealed, cond='is_finished')
+    )
+    
+    def __init__(self, snapshot, *args, **kwargs):
+        self.snapshot = snapshot
+        super().__init__(snapshot, *args, **kwargs)
+        
+    def can_start(self) -> bool:
+        return self.snapshot.seed and self.snapshot.seed.uri
+        
+    def is_finished(self) -> bool:
+        return not self.snapshot.has_pending_archiveresults()
+        
+    def on_started(self):
+        self.snapshot.create_pending_archiveresults()
+        self.snapshot.bump_retry_at(seconds=60)
+        self.snapshot.save()
+        
+    def on_sealed(self):
+        self.snapshot.retry_at = None
+        self.snapshot.save()
+
+class ArchiveResultMachine(StateMachine, strict_states=True):
+    """State machine for managing ArchiveResult lifecycle."""
+    
+    model: ArchiveResult
+    
+    # States
+    queued = State(value=ArchiveResult.ArchiveResultStatus.QUEUED, initial=True)
+    started = State(value=ArchiveResult.ArchiveResultStatus.STARTED)
+    backoff = State(value=ArchiveResult.ArchiveResultStatus.BACKOFF)
+    succeeded = State(value=ArchiveResult.ArchiveResultStatus.SUCCEEDED, final=True)
+    failed = State(value=ArchiveResult.ArchiveResultStatus.FAILED, final=True)
+    
+    # Tick Event
+    tick = (
+        queued.to.itself(unless='can_start', internal=True) |
+        queued.to(started, cond='can_start') |
+        started.to.itself(unless='is_finished', internal=True) |
+        started.to(succeeded, cond='is_succeeded') |
+        started.to(failed, cond='is_failed') |
+        started.to(backoff, cond='is_backoff') |
+        backoff.to.itself(unless='can_start', internal=True) |
+        backoff.to(started, cond='can_start') |
+        backoff.to(succeeded, cond='is_succeeded') |
+        backoff.to(failed, cond='is_failed')
+    )
+
+    def __init__(self, archiveresult, *args, **kwargs):
+        self.archiveresult = archiveresult
+        super().__init__(archiveresult, *args, **kwargs)
+        
+    def can_start(self) -> bool:
+        return self.archiveresult.snapshot and self.archiveresult.snapshot.is_started()
+    
+    def is_succeeded(self) -> bool:
+        return self.archiveresult.output_exists()
+    
+    def is_failed(self) -> bool:
+        return not self.archiveresult.output_exists()
+    
+    def is_backoff(self) -> bool:
+        return self.archiveresult.status == ArchiveResult.ArchiveResultStatus.BACKOFF
+
+    def on_started(self):
+        self.archiveresult.start_ts = timezone.now()
+        self.archiveresult.create_output_dir()
+        self.archiveresult.bump_retry_at(seconds=60)
+        self.archiveresult.save()
+
+    def on_backoff(self):
+        self.archiveresult.bump_retry_at(seconds=60)
+        self.archiveresult.save()
+
+    def on_succeeded(self):
+        self.archiveresult.end_ts = timezone.now()
+        self.archiveresult.save()
+
+    def on_failed(self):
+        self.archiveresult.end_ts = timezone.now()
+        self.archiveresult.save()
+        
+    def after_transition(self, event: str, source: State, target: State):
+        print(f"after '{event}' from '{source.id}' to '{target.id}'")
+        # self.archiveresult.save_merkle_index()
+        # self.archiveresult.save_html_index()
+        # self.archiveresult.save_json_index()
+        return "after_transition"

archivebox/crawls/actors.py

@@ -0,0 +1,69 @@
+__package__ = 'archivebox.crawls'
+
+from typing import ClassVar
+
+from rich import print
+
+from django.db.models import QuerySet
+
+from crawls.models import Crawl
+
+from actors.actor import ActorType
+
+
+class CrawlActor(ActorType[Crawl]):
+    
+    QUERYSET: ClassVar[QuerySet] = Crawl.objects.filter(status='queued')
+    CLAIM_WHERE: ClassVar[str] = 'status = "queued"'  # the WHERE clause to filter the objects when atomically getting the next object from the queue
+    CLAIM_SET: ClassVar[str] = 'status = "started"'   # the SET clause to claim the object when atomically getting the next object from the queue
+    CLAIM_ORDER: ClassVar[str] = 'created_at DESC'    # the ORDER BY clause to sort the objects with when atomically getting the next object from the queue
+    CLAIM_FROM_TOP: ClassVar[int] = 50                # the number of objects to consider when atomically getting the next object from the queue
+    
+    # model_type: Type[ModelType]
+    MAX_CONCURRENT_ACTORS: ClassVar[int] = 4               # min 2, max 8, up to 60% of available cpu cores
+    MAX_TICK_TIME: ClassVar[int] = 60                          # maximum duration in seconds to process a single object
+    
+    def claim_sql_where(self) -> str:
+        """override this to implement a custom WHERE clause for the atomic claim step e.g. "status = 'queued' AND locked_by = NULL" """
+        return self.CLAIM_WHERE
+    
+    def claim_sql_set(self) -> str:
+        """override this to implement a custom SET clause for the atomic claim step e.g. "status = 'started' AND locked_by = {self.pid}" """
+        return self.CLAIM_SET
+    
+    def claim_sql_order(self) -> str:
+        """override this to implement a custom ORDER BY clause for the atomic claim step e.g. "created_at DESC" """
+        return self.CLAIM_ORDER
+    
+    def claim_from_top(self) -> int:
+        """override this to implement a custom number of objects to consider when atomically claiming the next object from the top of the queue"""
+        return self.CLAIM_FROM_TOP
+        
+    def tick(self, obj: Crawl) -> None:
+        """override this to process the object"""
+        print(f'[blue]🏃‍♂️ {self}.tick()[/blue]', obj.abid or obj.id)
+        # For example:
+        # do_some_task(obj)
+        # do_something_else(obj)
+        # obj._model.objects.filter(pk=obj.pk, status='started').update(status='success')
+        # raise NotImplementedError('tick() must be implemented by the Actor subclass')
+    
+    def on_shutdown(self, err: BaseException | None=None) -> None:
+        print(f'[grey53]🏃‍♂️ {self}.on_shutdown() SHUTTING DOWN[/grey53]', err or '[green](gracefully)[/green]')
+        # abx.pm.hook.on_actor_shutdown(self)
+        
+    def on_tick_start(self, obj: Crawl) -> None:
+        # print(f'🏃‍♂️ {self}.on_tick_start()', obj.abid or obj.id)
+        # abx.pm.hook.on_actor_tick_start(self, obj_to_process)
+        # self.timer = TimedProgress(self.MAX_TICK_TIME, prefix='      ')
+        pass
+    
+    def on_tick_end(self, obj: Crawl) -> None:
+        # print(f'🏃‍♂️ {self}.on_tick_end()', obj.abid or obj.id)
+        # abx.pm.hook.on_actor_tick_end(self, obj_to_process)
+        # self.timer.end()
+        pass
+    
+    def on_tick_exception(self, obj: Crawl, err: BaseException) -> None:
+        print(f'[red]🏃‍♂️ {self}.on_tick_exception()[/red]', obj.abid or obj.id, err)
+        # abx.pm.hook.on_actor_tick_exception(self, obj_to_process, err)

archivebox/crawls/models.py

@@ -1,13 +1,20 @@
 __package__ = 'archivebox.crawls'
 
+from typing import TYPE_CHECKING
 from django_stubs_ext.db.models import TypedModelMeta
 
+from datetime import timedelta
+
 from django.db import models
-from django.db.models import Q
 from django.core.validators import MaxValueValidator, MinValueValidator 
 from django.conf import settings
-from django.utils import timezone
 from django.urls import reverse_lazy
+from django.utils import timezone
+
+from statemachine.mixins import MachineMixin
+
+if TYPE_CHECKING:
+    from core.models import Snapshot
 
 from seeds.models import Seed
 
@@ -41,8 +48,9 @@ class CrawlSchedule(ABIDModel, ModelWithHealthStats):
         """The base crawl that each new scheduled job should copy as a template"""
         return self.crawl_set.first()
 
+    
 
-class Crawl(ABIDModel, ModelWithHealthStats):
+class Crawl(ABIDModel, ModelWithHealthStats, MachineMixin):
     """
     A single session of URLs to archive starting from a given Seed and expanding outwards. An "archiving session" so to speak.
 
@@ -55,16 +63,29 @@ class Crawl(ABIDModel, ModelWithHealthStats):
     abid_prefix = 'crl_'
     abid_ts_src = 'self.created_at'
     abid_uri_src = 'self.seed.uri'
-    abid_subtype_src = 'self.persona_id'
+    abid_subtype_src = 'self.persona'
     abid_rand_src = 'self.id'
     abid_drift_allowed = True
+    
+    state_field_name = 'status'
+    state_machine_name = 'crawls.statemachines.CrawlMachine'
+    state_machine_attr = 'sm'
+    bind_events_as_methods = True
+
+    class CrawlStatus(models.TextChoices):
+        QUEUED = 'queued', 'Queued'
+        STARTED = 'started', 'Started'
+        SEALED = 'sealed', 'Sealed'
 
+    status = models.CharField(choices=CrawlStatus.choices, max_length=15, default=CrawlStatus.QUEUED, null=False, blank=False)
+    
     id = models.UUIDField(primary_key=True, default=None, null=False, editable=False, unique=True, verbose_name='ID')
     abid = ABIDField(prefix=abid_prefix)
 
     created_by = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, default=None, null=False, related_name='crawl_set')
     created_at = AutoDateTimeField(default=None, null=False, db_index=True)
     modified_at = models.DateTimeField(auto_now=True)
+    
 
     seed = models.ForeignKey(Seed, on_delete=models.PROTECT, related_name='crawl_set', null=False, blank=False)
     max_depth = models.PositiveSmallIntegerField(default=0, validators=[MinValueValidator(0), MaxValueValidator(4)])
@@ -79,7 +100,7 @@ class Crawl(ABIDModel, ModelWithHealthStats):
     # schedule = models.JSONField()
     # config = models.JSONField()
     
-    # snapshot_set: models.Manager['Snapshot']
+    snapshot_set: models.Manager['Snapshot']
     
 
     class Meta(TypedModelMeta):
@@ -102,6 +123,28 @@ class Crawl(ABIDModel, ModelWithHealthStats):
     @property
     def api_docs_url(self) -> str:
         return '/api/v1/docs#/Core%20Models/api_v1_core_get_crawl'
+    
+    def has_pending_archiveresults(self) -> bool:
+        from core.models import ArchiveResult
+        
+        pending_statuses = [ArchiveResult.ArchiveResultStatus.QUEUED, ArchiveResult.ArchiveResultStatus.STARTED]
+        
+        snapshot_ids = self.snapshot_set.values_list('id', flat=True)
+        pending_archiveresults = ArchiveResult.objects.filter(snapshot_id__in=snapshot_ids, status__in=pending_statuses)
+        return pending_archiveresults.exists()
+    
+    def create_root_snapshot(self) -> 'Snapshot':
+        from core.models import Snapshot
+        
+        root_snapshot, _ = Snapshot.objects.get_or_create(
+            crawl=self,
+            url=self.seed.uri,
+        )
+        return root_snapshot
+    
+    def bump_retry_at(self, seconds: int = 10):
+        self.retry_at = timezone.now() + timedelta(seconds=seconds)
+        self.save()
 
 
 class Outlink(models.Model):

archivebox/crawls/statemachines.py

@@ -0,0 +1,48 @@
+__package__ = 'archivebox.crawls'
+
+from statemachine import State, StateMachine
+
+from crawls.models import Crawl
+
+# State Machine Definitions
+#################################################
+
+
+class CrawlMachine(StateMachine, strict_states=True):
+    """State machine for managing Crawl lifecycle."""
+    
+    model: Crawl
+    
+    # States
+    queued = State(value=Crawl.CrawlStatus.QUEUED, initial=True)
+    started = State(value=Crawl.CrawlStatus.STARTED)
+    sealed = State(value=Crawl.CrawlStatus.SEALED, final=True)
+    
+    # Tick Event
+    tick = (
+        queued.to.itself(unless='can_start', internal=True) |
+        queued.to(started, cond='can_start') |
+        started.to.itself(unless='is_finished', internal=True) |
+        started.to(sealed, cond='is_finished')
+    )
+    
+    def __init__(self, crawl, *args, **kwargs):
+        self.crawl = crawl
+        super().__init__(crawl, *args, **kwargs)
+        
+    def can_start(self) -> bool:
+        return self.crawl.seed and self.crawl.seed.uri
+        
+    def is_finished(self) -> bool:
+        return not self.crawl.has_pending_archiveresults()
+
+
+        
+    def on_started(self):
+        self.crawl.create_root_snapshot()
+        self.crawl.bump_retry_at(seconds=10)
+        self.crawl.save()
+        
+    def on_sealed(self):
+        self.crawl.retry_at = None
+        self.crawl.save()

archivebox/pkgs/abx-plugin-singlefile/abx_plugin_singlefile/__init__.py

@@ -29,7 +29,7 @@ def get_EXTRACTORS():
         'singlefile': SINGLEFILE_EXTRACTOR,
     }
 
-# @abx.hookimpl
-# def get_INSTALLED_APPS():
-#     # needed to load ./models.py
-#     return [__package__]
[email protected]
+def get_INSTALLED_APPS():
+    # needed to load ./models.py
+    return [__package__]

archivebox/pkgs/abx-plugin-singlefile/abx_plugin_singlefile/actors.py

@@ -0,0 +1,27 @@
+__package__ = 'abx_plugin_singlefile'
+
+from typing import ClassVar
+from django.db.models import QuerySet
+from django.utils.functional import classproperty
+
+from actors.actor import ActorType
+
+from .models import SinglefileResult
+
+
+class SinglefileActor(ActorType[SinglefileResult]):
+    CLAIM_ORDER: ClassVar[str] = 'created_at DESC'
+    CLAIM_WHERE: ClassVar[str] = 'status = "queued" AND extractor = "favicon"'
+    CLAIM_SET: ClassVar[str] = 'status = "started"'
+    
+    @classproperty
+    def QUERYSET(cls) -> QuerySet:
+        return SinglefileResult.objects.filter(status='queued')
+
+    def tick(self, obj: SinglefileResult):
+        print(f'[grey53]{self}.tick({obj.abid or obj.id}, status={obj.status}) remaining:[/grey53]', self.get_queue().count())
+        updated = SinglefileResult.objects.filter(id=obj.id, status='started').update(status='success') == 1
+        if not updated:
+            raise Exception(f'Failed to update {obj.abid or obj.id}, interrupted by another actor writing to the same object')
+        obj.refresh_from_db()
+        obj.save()

archivebox/pkgs/abx-spec-archivebox/abx_spec_archivebox/states.py

@@ -20,6 +20,17 @@ from django.urls import reverse_lazy
 
 from pathlib import Path
 
+# Glossary:
+#   - startup: when a new process is spawned
+#   - shutdown: when a process is exiting
+#   - start: at the beginning of some python code block
+#   - end: at the end of some python code block
+#   - queue: a django queryset of objects of a single type that are waiting to be processed
+#   - actor: a long-running daemon process that wakes up and processes a single object from a queue at a time
+#   - plugin: a python package that defines some hookimpls based on hookspecs exposed by ABX
+#   - object: an instance of a django model that represents a single row in the database
+
+
 # ORCHESTRATOR:
 # An orchestrator is a single long-running daemon process that manages spawning and killing actors for different queues of objects.
 # The orchestrator first starts when the archivebox starts, and it stops when archivebox is killed.
@@ -74,8 +85,8 @@ from pathlib import Path
 # On startup an actor should fire abx.pm.hook.on_actor_startup(object) and on exit it should fire abx.pm.hook.on_actor_exit(object) (both syncronous hooks that can be used by plugins to register any startup/cleanup code).
 # An ActorType defines the following hookspecs for plugins to hook into its behavior:
 #   - abx.pm.hook.on_actor_startup(actor, queue)
-#   - abx.pm.hook.on_actor_tick_started(actor, object)
-#   - abx.pm.hook.on_actor_tick_finished(actor, object)
+#   - abx.pm.hook.on_actor_tick_start(actor, object)
+#   - abx.pm.hook.on_actor_tick_end(actor, object)
 #   - abx.pm.hook.on_actor_tick_exception(actor, object, exception)
 #   - abx.pm.hook.on_actor_shutdown(actor)
 
@@ -107,8 +118,8 @@ from pathlib import Path
 #   - external API calls (e.g. uploading to s3, firing a webhook, writing to a logfile, etc.)
 #   - DO NOT use side effects to directly mutate other objects state or trigger other state transitions
 # ABX defines the following hookspecs for plugins to hook into transition behavior:
-#   - abx.pm.hook.on_transition_<objecttype>_from_abx_to_xyz_started(object)
-#   - abx.pm.hook.on_transition_<objecttype>_from_abx_to_xyz_succeeded(object)
+#   - abx.pm.hook.on_transition_<objecttype>_from_abx_to_xyz_start(object)
+#   - abx.pm.hook.on_transition_<objecttype>_from_abx_to_xyz_end(object)
 
 # READ:
 # A read() method is a function defined for a given ActorType that performs a single read from the DB and/or other read models like django cache, filesystem, in-memory caches, etc.

archivebox/seeds/models.py

@@ -1,19 +1,8 @@
 __package__ = 'archivebox.seeds'
 
 
-from datetime import datetime
-
-from django_stubs_ext.db.models import TypedModelMeta
-
 from django.db import models
-from django.db.models import Q
-from django.core.validators import MaxValueValidator, MinValueValidator 
 from django.conf import settings
-from django.utils import timezone
-from django.utils.functional import cached_property
-from django.urls import reverse_lazy
-
-from pathlib import Path
 
 
 from abid_utils.models import ABIDModel, ABIDField, AutoDateTimeField, ModelWithHealthStats
@@ -47,7 +36,10 @@ class Seed(ABIDModel, ModelWithHealthStats):
     abid_rand_src = 'self.id'
     abid_drift_allowed = True
     
-    uri = models.URLField(max_length=255, blank=False, null=False, unique=True)              # unique source location where URLs will be loaded from
+    id = models.UUIDField(primary_key=True, default=None, null=False, editable=False, unique=True, verbose_name='ID')
+    abid = ABIDField(prefix=abid_prefix)
+    
+    uri = models.URLField(max_length=2000, blank=False, null=False)                          # unique source location where URLs will be loaded from
     
     extractor = models.CharField(default='auto', max_length=32)   # suggested extractor to use to load this URL source
     tags_str = models.CharField(max_length=255, null=False, blank=True, default='')          # tags to attach to any URLs that come from this source
@@ -64,4 +56,10 @@ class Seed(ABIDModel, ModelWithHealthStats):
         #      pocketapi://
         #      s3://
         #      etc..
-        return self.uri.split('://')[0].lower()
+        return self.uri.split('://', 1)[0].lower()
+
+    class Meta:
+        verbose_name = 'Seed'
+        verbose_name_plural = 'Seeds'
+        
+        unique_together = (('created_by', 'uri', 'extractor'),)

pyproject.toml

@@ -61,7 +61,7 @@ dependencies = [
     "pluggy>=1.5.0",
     "requests>=2.32.3",
     "dateparser>=1.2.0",
-    "tzdata>=2024.2",                 # needed for dateparser {TZ: UTC} on some systems: https://github.com/ArchiveBox/ArchiveBox/issues/1553
+    "tzdata>=2024.2", # needed for dateparser {TZ: UTC} on some systems: https://github.com/ArchiveBox/ArchiveBox/issues/1553
     "feedparser>=6.0.11",
     "w3lib>=2.2.1",
     "rich>=13.8.0",
@@ -86,40 +86,35 @@ dependencies = [
     "yt-dlp>=2024.8.6", # for: media"
     ############# Plugin Dependencies ################
     "abx>=0.1.0",
-
     "abx-spec-pydantic-pkgr>=0.1.0",
     "abx-spec-config>=0.1.0",
     "abx-spec-archivebox>=0.1.0",
     "abx-spec-django>=0.1.0",
     "abx-spec-extractor>=0.1.0",
     "abx-spec-searchbackend>=0.1.0",
-
     "abx-plugin-default-binproviders>=2024.10.24",
     "abx-plugin-pip>=2024.10.24",
     "abx-plugin-npm>=2024.10.24",
     "abx-plugin-playwright>=2024.10.24",
     "abx-plugin-puppeteer>=2024.10.28",
-
     "abx-plugin-ripgrep-search>=2024.10.28",
     "abx-plugin-sqlitefts-search>=2024.10.28",
     "abx-plugin-sonic-search>=2024.10.28",
     "abx-plugin-ldap-auth>=2024.10.28",
-
     "abx-plugin-curl>=2024.10.27",
     "abx-plugin-wget>=2024.10.28",
     "abx-plugin-git>=2024.10.28",
     "abx-plugin-chrome>=2024.10.28",
     "abx-plugin-ytdlp>=2024.10.28",
-    
     "abx-plugin-title>=2024.10.27",
     "abx-plugin-favicon>=2024.10.27",
     # "abx-plugin-headers>=2024.10.27",
     "abx-plugin-archivedotorg>=2024.10.28",
-
     "abx-plugin-singlefile>=2024.10.28",
     "abx-plugin-readability>=2024.10.28",
     "abx-plugin-mercury>=2024.10.28",
     "abx-plugin-htmltotext>=2024.10.28",
+    "python-statemachine>=2.3.6",
 ]
 
 [project.optional-dependencies]

uv.lock

@@ -661,6 +661,7 @@ dependencies = [
     { name = "pydantic-settings" },
     { name = "python-benedict", extra = ["io", "parse"] },
     { name = "python-crontab" },
+    { name = "python-statemachine" },
     { name = "requests" },
     { name = "rich" },
     { name = "rich-argparse" },
@@ -789,6 +790,7 @@ requires-dist = [
     { name = "python-benedict", extras = ["io", "parse"], specifier = ">=0.33.2" },
     { name = "python-crontab", specifier = ">=3.2.0" },
     { name = "python-ldap", marker = "extra == 'ldap'", specifier = ">=3.4.3" },
+    { name = "python-statemachine", specifier = ">=2.3.6" },
     { name = "requests", specifier = ">=2.32.3" },
     { name = "requests-tracker", marker = "extra == 'debug'", specifier = ">=0.3.3" },
     { name = "rich", specifier = ">=13.8.0" },
@@ -2729,6 +2731,15 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/a4/62/02da182e544a51a5c3ccf4b03ab79df279f9c60c5e82d5e8bec7ca26ac11/python_slugify-8.0.4-py2.py3-none-any.whl", hash = "sha256:276540b79961052b66b7d116620b36518847f52d5fd9e3a70164fc8c50faa6b8", size = 10051 },
 ]
 
+[[package]]
+name = "python-statemachine"
+version = "2.3.6"
+source = { registry = "https://pypi.org/simple" }
+sdist = { url = "https://files.pythonhosted.org/packages/20/c9/7034a362ce151f9fa0ead5630727a16122f7a5ed235d42447910dff95b6a/python_statemachine-2.3.6.tar.gz", hash = "sha256:9cb4040ca7f2158d3cd46f36a77b420b6ef95a90223928a7f3cab232a70bd560", size = 36735 }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/39/04/19a44b549cbaae1ac6c2acc58afb96b71209da866713877f40aab2f45de6/python_statemachine-2.3.6-py3-none-any.whl", hash = "sha256:0001b02cbe2f5b2420c423b5b3e3a33915447ac6d9735219c929e2378d454f5f", size = 41529 },
+]
+
 [[package]]
 name = "python-stdnum"
 version = "1.20"