Bug Fix - S3DeleteObjectsOperator will try and delete all keys

[njrs92]

There is a bug when an empty list is passed into S3DeleteObjectsOperator from another task it will try and deleted all keys on the bucket. While the intent of passing in an empty prefix might be to delete all keys, the intent of passing in a empty keys list would be to delete no keys.

This is because I assume templating does something with init so the check for this condition is not run.

The case is:
In line 379 because keys is an empty list it is false so keys is now assigned the return values from list_keys which when passed no prefix will return all keys.

The change is to move the xor check of keys or prefix is inside the execute function to ensure it is checked at run time

[boring-cyborg]

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[potiuk]

Yeah. Good call. Could you please add a unit test covering it ?

I also think the test should remain in the init as well.. passing both key and prefix at init should fail dag parsing (fail as early as possible when the input parameters are wrong).

[josh-fell]

This is because I assume templating does something with init so the check for this condition is not run.

@njrs92 For some context here, the values of XComArgs or templated/Jinja expressions aren't evaluated until the execute() method of an operator so the eval in the __init__() would be a false-positive in the use case you describe.

[potiuk]

Hello - how about the unit test :) ? I'd love to merge that one.

[njrs92]

Sorry got a bit distracted working on other stuff. I will commit the unit tests shortly

[njrs92]

Sorry my line endings messed up the diff and there is a bunch of unrelated changes that got committed accidentally.

[github-actions]

The PR is likely OK to be merged with just subset of tests for default Python and Database versions without running the full matrix of tests, because it does not modify the core of Airflow. If the committers decide that the full tests matrix is needed, they will add the label 'full tests needed'. Then you should rebase to the latest main or amend the last commit of the PR, and push it with --force-with-lease.

[boring-cyborg]

Awesome work, congrats on your first merged pull request!