CELERY_RESULT_EXPIRES does not prevent backend.cleanup task

[kgeographer]

I have been using django-celery-results v1.0.2 in an app for a few years successfully. No tasks are ever deleted automatically, and that is essential to my application - result attributes are used in various ways permanently. Occasionally I will clear out some mundane tasks, but certain ones are crucial, and not a huge number.

Now upgrading and updating, to Django 4 from 2, and django-celery-results to 2.5.0, I find that all tasks are wiped daily. I understand this is standard behavior, and that a CELERY_RESULT_EXPIRES = None line in settings.py should prevent the cleanup task from running, but it hasn't.

How can I stop the cleanup?

[hetvi01]

Once cross-verify the version of celery you are using.

In the latest stable version (5.4) of celery, the configuration constant for this setting is CELERY_TASK_RESULT_EXPIRES, not CELERY_RESULT_EXPIRES.

JFYI: Versions of celery greater than 3.0 use CELERY_TASK_RESULT_EXPIRES. I am not certain about the constants used in versions prior to that.

Ensure that the version of celery you are using supports CELERY_RESULT_EXPIRES else try to change the constant.

[saz]

FYI: Since Celery 4, CELERY_RESULT_EXPIRES should be used. CELERY_TASK_RESULT_EXPIRES is still valid, but might be removed in the future.

See also https://github.com/celery/celery/blob/f51c2bd8c175f5ea235da684aed870e5884fa941/docs/history/whatsnew-4.4.rst#configuration