Option to exit TaskTiger after a certain amount of time (#324)

This can be useful to avoid memory leaks when using a non-forking executor.

tasktiger/tasktiger.py

@@ -399,6 +399,7 @@ def run_worker(
         max_workers_per_queue: Optional[int] = None,
         store_tracebacks: Optional[bool] = None,
         executor_class: Optional[Type[Executor]] = None,
+        exit_after: Optional[datetime.timedelta] = None,
     ) -> None:
         """
         Main worker entry point method.
@@ -423,7 +424,7 @@ def run_worker(
                 store_tracebacks=store_tracebacks,
                 executor_class=executor_class,
             )
-            worker.run()
+            worker.run(exit_after=exit_after)
         except Exception:
             self.log.exception("Unhandled exception")
             raise
@@ -698,6 +699,11 @@ def would_process_configured_queue(self, queue_name: str) -> bool:
     "--executor",
     help="Task executor. Possible values are sync or fork (default).",
 )
+@click.option(
+    "--exit-after",
+    type=click.INT,
+    help="Exit TaskTiger after the time in minutes has elapsed.",
+)
 @click.pass_context
 def run_worker(
     context: Any,
@@ -711,23 +717,32 @@ def run_worker(
     max_workers_per_queue: Optional[int] = None,
     store_tracebacks: Optional[bool] = None,
     executor: Optional[str] = "fork",
+    exit_after: Optional[int] = None,
 ) -> None:
     conn = redis.Redis(
         host, int(port or 6379), int(db or 0), password, decode_responses=True
     )
     tiger = context.obj or TaskTiger(setup_structlog=True, connection=conn)
+
     executor_class: Type[Executor]
     if not executor or executor == "fork":
         executor_class = ForkExecutor
     elif executor == "sync":
         executor_class = SyncExecutor
     else:
         raise click.ClickException("Invalid executor.")
+
+    if exit_after:
+        exit_after_td = datetime.timedelta(minutes=exit_after)
+    else:
+        exit_after_td = None
+
     tiger.run_worker(
         queues=queues,
         module=module,
         exclude_queues=exclude_queues,
         max_workers_per_queue=max_workers_per_queue,
         store_tracebacks=store_tracebacks,
         executor_class=executor_class,
+        exit_after=exit_after_td,
     )

tasktiger/worker.py

@@ -1,3 +1,4 @@
+import datetime
 import hashlib
 import json
 import os
@@ -971,13 +972,21 @@ def store_task_execution(self, tasks: List[Task], execution: Dict) -> None:
 
             pipeline.execute()
 
-    def run(self, once: bool = False, force_once: bool = False) -> None:
+    def run(
+        self,
+        once: bool = False,
+        force_once: bool = False,
+        exit_after: Optional[datetime.timedelta] = None,
+    ) -> None:
         """
         Main loop of the worker.
 
-        Use once=True to execute any queued tasks and then exit.
-        Use force_once=True with once=True to always exit after one processing
-        loop even if tasks remain queued.
+        Args:
+            once: If True, execute any queued tasks and then exit.
+            force_once: If set to True together with once, always exit after
+                one processing loop even if tasks remain queued.
+            exit_after: If set, exit the worker after the given duration
+                elapses.
         """
 
         self.log.info(
@@ -988,8 +997,16 @@ def run(self, once: bool = False, force_once: bool = False) -> None:
             single_worker_queues=sorted(self.single_worker_queues),
             max_workers=self.max_workers_per_queue,
             executor=self.executor.__class__.__name__,
+            exit_after=str(exit_after) if exit_after else None,
         )
 
+        if exit_after:
+            exit_after_dt = (
+                datetime.datetime.now(datetime.timezone.utc) + exit_after
+            )
+        else:
+            exit_after_dt = None
+
         if not self.scripts.can_replicate_commands:
             # Older Redis versions may create additional overhead when
             # executing pipelines.
@@ -1034,6 +1051,12 @@ def run(self, once: bool = False, force_once: bool = False) -> None:
                 self._uninstall_signal_handlers()
                 if once and (not self._queue_set or force_once):
                     break
+                if (
+                    exit_after_dt
+                    and datetime.datetime.now(datetime.timezone.utc)
+                    > exit_after_dt
+                ):
+                    break
                 if self._stop_requested:
                     raise KeyboardInterrupt()
         except KeyboardInterrupt: