Fix _get_count in sensor_helper.py

[fuatcakici]

Fixes an overlooked part of #39616

Currently, the _get_count function in sensor_helper.py does not return the number of the Dag Runs where all the sub tasks in a task group for all the datetimes given in the dttm_filter have succeeded, but instead just returns 1 if they are all complete. However, this is not the expected behaviour wherever this function is used (namely in the run function in WorkflowTrigger and poke function in ExternalTaskSensor)

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[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 5 days if no further activity occurs. Thank you for your contributions.

[eladkal]

@pankajastro @nathadfield Can you check if this fix still needed?

[nathadfield]

@eladkal Well, I fixed the original issue. It seems this is related to something I overlooked but I'm not aware that it's a problem.

[fuatcakici]

@nathadfield yes, I was also waiting for that issue to be fixed, so thanks! But basically here, there are no issues if there is only one execution date set for the execution_dates parameter in the WorkflowTrigger. But once you set more than one execution date, it will just hang since _get_count will give 1 once all the tasks finish, but WorkflowTrigger will wait until it gives len(execution_dates), which will not happen.

[nathadfield]

@fuatcakici Ok, well, this is your PR but it originally had some issues. Can I suggest that you rebase it and then this should trigger the tests again?

[fuatcakici]

@nathadfield Rebased 🙂

[nathadfield]

@fuatcakici Great! It looks like all the tests passed too although I don't have the ability to merge. Maybe @eladkal or @pankajastro might be able to oblige?

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed in 5 days if no further activity occurs. Thank you for your contributions.

[eladkal]

@fuatcakici can you rebase and resolve conflicts?
Also we need unit test to avoid regression

[fuatcakici]

@eladkal Rebased once again and all the tests succeeded 🙂 There are of course many changes happening in real time so it is virtually impossible for the branch to stay constantly up-to-date

[eladkal]

Since @nathadfield confirmed it's a bug fix, I am happy to merge once you add a unit test to cover this change. This is needed to making sure we won't have future regression