Expose --max-idle-time RQ flag in rqworker management command

[indispeq]

Django-rq currently does not expose the --max-idle-time flag that python-rq is able to use under the hood to gracefully shut down a worker after a given amount of seconds. Exposing this functionality proves useful in the event when django-rq workers are run within an autoscaling situation where scale-down time cannot be controlled (e.g.: Azure Container Apps).

By running the worker with ./manage.py rqworker --max-idle-time 60 default the worker can gracefully shutdown before it gets killed by autoscaling, avoiding interrupted jobs that fail with an error of:

Work-horse terminated unexpectedly; waitpid returned 15 (signal 15);

Since --max-jobs is already exposed in the rqworker management command, exposing this option is trivial.

Testing process:

• When the flag is not used, the worker functions as expected.
• When the flag is used, the worker exited after 60 seconds:

webapp@e15bb6d1e70d$ ./manage.py rqworker --max-idle-time 60 default
13:03:05 Worker rq:worker:05c2a12455804f9d8a3555f5d004837d started with PID 59, version 2.0.0
13:03:05 Subscribing to channel rq:pubsub:05c2a12455804f9d8a3555f5d004837d
13:03:05 *** Listening on default...
13:03:05 Cleaning registries for queue: default
13:04:05 Worker rq:worker:05c2a12455804f9d8a3555f5d004837d: idle for 60 seconds, quitting
13:04:05 Unsubscribing from channel rq:pubsub:05c2a12455804f9d8a3555f5d004837d