Fix KeyError when k8s omits optional reason field in container waiting status #60527

[anishgirianish]

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Closes #60527

The k8s API spec defines reason and message as optional fields in ContainerStateWaiting, but the code assumed they always exist. This caused KeyError: 'reason' crashes in the job watcher, leaving execution slots locked until scheduler restart.

Fixed by using .get() for safe access to these optional fields.

Added test case for missing reason scenario.

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[dthauvin]

hi @anishgirianish any clue when this fix will be attached to a Milestone and released ?

[anishgirianish]

Hi @dthauvin, thanks for your interest in this fix! For questions about milestones and release timelines, the maintainers would have a better idea. @jedcunningham @hussein-awala, would you be able to help with this? And whenever you have a moment, I'd really appreciate your feedback on this PR as well. Thank you!

[Nataneljpwd]

Looks great!

I would maybe add a link to the request spec where it states that the field is optional as a comment to the code so that no one changes it later on

[jscheffl]

Cool! Thanks for the fix!

(And I'd really love if K8s generated API bindings would use fully-typed objects such that these type problems can be directly found by static type checks...)