This document describes the current stable version of Celery (5.2). For development docs, go here.

celery.worker.worker

WorkController can be used to instantiate in-process workers.

The command-line interface for the worker is in celery.bin.worker, while the worker program is in celery.apps.worker.

The worker program is responsible for adding signal handlers, setting up logging, etc. This is a bare-bones worker without global side-effects (i.e., except for the global state stored in celery.worker.state).

The worker consists of several components, all managed by bootsteps (mod:celery.bootsteps).

class celery.worker.worker.WorkController(app=None, hostname=None, **kwargs)

Unmanaged worker instance.

class Blueprint(steps=None, name=None, on_start=None, on_close=None, on_stopped=None)

Worker bootstep blueprint.

default_steps = {'celery.worker.autoscale:WorkerComponent', 'celery.worker.components:Beat', 'celery.worker.components:Consumer', 'celery.worker.components:Hub', 'celery.worker.components:Pool', 'celery.worker.components:StateDB', 'celery.worker.components:Timer'}

name = 'Worker'

app = None

blueprint = None

exitcode = None

contains the exit code if a SystemExit event is handled.

info()

on_after_init(**kwargs)

on_before_init(**kwargs)

on_close()

on_consumer_ready(consumer)

on_init_blueprint()

on_start()

on_stopped()

pidlock = None

pool = None

prepare_args(**kwargs)

register_with_event_loop(hub)

reload(modules=None, reload=False, reloader=None)

rusage()

semaphore = None

setup_defaults(concurrency=None, loglevel='WARN', logfile=None, task_events=None, pool=None, consumer_cls=None, timer_cls=None, timer_precision=None, autoscaler_cls=None, pool_putlocks=None, pool_restarts=None, optimization=None, O=None, statedb=None, time_limit=None, soft_time_limit=None, scheduler=None, pool_cls=None, state_db=None, task_time_limit=None, task_soft_time_limit=None, scheduler_cls=None, schedule_filename=None, max_tasks_per_child=None, prefetch_multiplier=None, disable_rate_limits=None, worker_lost_wait=None, max_memory_per_child=None, **_kw)

setup_includes(includes)

setup_instance(queues=None, ready_callback=None, pidfile=None, include=None, use_eventloop=None, exclude_queues=None, **kwargs)

setup_queues(include, exclude=None)

should_use_eventloop()

signal_consumer_close()

start()

property state

stats()

stop(in_sighandler=False, exitcode=None)

Graceful shutdown of the worker server.

terminate(in_sighandler=False)

Not so graceful shutdown of the worker server.