If there’s a task failure in an upstream task and I am waiting on it to complete (using

wait_for

), it’s never triggered, rather goes into an undocumented

NotReady

state. To overcome this, I have to set

.result(raise_on_failure=False)

on the upstream task. See images below for states. See screengrabs 👇 - left fails, right works. This seems like a common DAG use-case which should be handled well by prefect, how do we wait on a set of upstream tasks to complete and then perform a cleanup / notification at the end (with an aggregate of results from all upstream tasks).

Thanks for the report!

wait_for

indicates that the upstream needs to complete successfully for the downstream to run.

Yeah ! that would make a lot more sense. This seems like a pretty common use-case where a downstream task needs to execute after all upstream ones are done - Completed or Failed.

+1 we currently use

@task(trigger=any_successful)

in Prefect 1, and are looking for something similar in Prefect 2