how to implement an on_revoked event in celery
Use AbortableTask as a template and create a RevokableTask class to your specification.
I have a task that retries often, and I would like a way for it to cleanup if it is revoked while it is in the retry state. It seems like there are a few options for doing this, and I'm wondering what the most acceptable/cleanest would be. Here's what I've thought of so far:

Custom Camera that picks up revoked tasks and calls on_revoked
Custom Event Consumer that knows to process on_revoked on tasks that get revoked
Using AbortableTasks and using abort instead of revoke (I'd really like to avoid this)

Are there any other options that I am missing?