celery shutdown worker after particular task

Question

I\'m using celery (solo pool with concurrency=1) and I want to be able to shut down the worker after a particular task has run. A caveat is that I want to avoid any possibility

Answer 1

If you shutdown the worker, after the task has completed, it won't re-queue again.

@task_postrun.connect(sender=add)
def shutdown(*args, **kwargs):
    app.control.broadcast('shutdown')

This will gracefully shutdown the worker after tasks is completed.

[2018-04-01 18:44:14,627: INFO/MainProcess] Connected to redis://localhost:6379/0
[2018-04-01 18:44:14,656: INFO/MainProcess] mingle: searching for neighbors
[2018-04-01 18:44:15,719: INFO/MainProcess] mingle: all alone
[2018-04-01 18:44:15,742: INFO/MainProcess] celery@foo ready.
[2018-04-01 18:46:28,572: INFO/MainProcess] Received task: celery_worker_stop.add[ac8a65ff-5aad-41a6-a2d6-a659d021fb9b]
[2018-04-01 18:46:28,585: INFO/ForkPoolWorker-4] Task celery_worker_stop.add[ac8a65ff-5aad-41a6-a2d6-a659d021fb9b] succeeded in 0.005628278013318777s: 3   
[2018-04-01 18:46:28,665: WARNING/MainProcess] Got shutdown from remote

Note: broadcast will shutdown all workers. If you want to shutdonw a specific worker, start worker with a name

celery -A celeryapp  worker -n self_killing --concurrency=1 --pool=solo

Now you can shutdown this with destination parameter.

app.control.broadcast('shutdown', destination=['celery@self_killing'])