Fix helm chart worker deployment without kerberos

[FloChehab]

Hello,

A small follow up to #11130 after some tests on the new chart : we shouldn't mount the kerberos-keytab volume
in the worker deployment if we are not using
kerberos in the first place.
(the previous behavior is breaking the chart)

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[mik-laj]

@potiuk Should we add unit tests? Did your patch with kerberos have the unittest?

[github-actions]

The Workflow run is cancelling this PR. It has some failed jobs matching ^Pylint$,^Static checks$,^Build docs$,^Spell check docs$,^Backport packages$,^Checks: Helm tests$,^Test OpenAPI*.

[github-actions]

The Workflow run is cancelling this PR. It has some failed jobs matching ^Pylint$,^Static checks$,^Build docs$,^Spell check docs$,^Backport packages$,^Checks: Helm tests$,^Test OpenAPI*.

[potiuk]

@potiuk Should we add unit tests? Did your patch with kerberos have the unittest?

Yes it had. Those are the very tests that are failing now :). So having tests did not help in this case.

[FloChehab]

I'll add a commit to fix the tests soon.

[potiuk]

@FloChehab The unit tests need updating. Also We have a discussion in #11657 about better unit tests for the chart. I would really love to hear your opinion as a "newcomer" whether the current unit tests are easy to understand and maintain and how do they compare to the proposal by @mik-laj in this issue.

[FloChehab]

@FloChehab The unit tests need updating. Also We have a discussion in #11657 about better unit tests for the chart. I would really love to hear your opinion as a "newcomer" whether the current unit tests are easy to understand and maintain and how do they compare to the proposal by @mik-laj in this issue.

I don't have experience with chart testing in general ; I'll play with the current setup for this PR (and the other ones that I have opened / will open) and try to give feedback.

[FloChehab]

Helm tests should be fixed (at least this part of the CI is green).

[mik-laj]

Hello.

We have a new test framework for Helm Chart. Can you add unit tests?

Best regards,
Kamil Breguła

[FloChehab]

Hello,

I've rebased on master and added a test to prevent kerberos from being mentioned in the render if it's not enabled (except in airflow's configmap because it would be a bit hard to change this behavior.

I'll be happy to adapt if necessary.

[github-actions]

The PR should be OK to be merged with just subset of tests as it does not modify Core of Airflow. The committers might merge it or can add a label 'full tests needed' and re-run it to run all tests if they see it is needed!

[FloChehab]

Thanks for the merge !