Are

on_completion

and

on_failure

hooks ignored when a task state is

Cached

? That seems to be the case, but AFAIK there’s no docs (https://github.com/PrefectHQ/prefect/issues/8967)

I think the answer to your question is yes - the hooks are ignored when a task already has a cached result. Looking in

engine.py

, the

on_completion

and

on_failure

hooks for tasks get called during the task run here. But if there's a cached result for a task, the Prefect API rejects the proposal to transition the task from PENDING -> RUNNING and instead returns the terminal state with the cached result attached. When that happens, the

state.is_running()

check here is false, and block of code with the hook call gets skipped.

Thanks very much 🙏 I wish there was a

on_exit

that would run no matter what the end state - but I’ve hacked something together to get around this (to trigger whether a task state is failed/completed/cached)

That might be worth opening a GitHub issue for; it sounds like a reasonable feature request.

Okay, thanks