Move KubernetesPodTrigger pod cleanup from cleanup() to on_kill()

[raushanprabhakar1]

KubernetesPodTrigger now cancels external work only through BaseTrigger.on_kill() instead of the previous cleanup() path that used safe_to_cancel() to distinguish user kills from triggerer restarts. Pod deletion on user-initiated kill is unchanged in intent: it still respects _fired_event, on_kill_action, and termination_grace_period; triggerer shutdown or redistribution no longer goes through pod-deletion logic in this trigger.

Unit tests were updated to assert on_kill behavior instead of cleanup / safe_to_cancel.

related: #65733

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Was generative AI tooling used to co-author this PR?

• Yes — Cursor (GPT-based agent)

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[jscheffl]

Sorry, need to request changes on this. This PR deletes too much.

Unfortunaltely is it not (yet) time to remove all Airflow 2.x support. The K8s provider package is still and needs still to be suoported with Airflow 2.11.x. Please revert the removal.

And yes this adds a bot of complexity but: The new on_kill() will only be available for Airflow 3.3.0++
This means the existing logic also needs to stay for all Airflow <3.3.0.

[raushanprabhakar1]

Hi @jscheffl , Thanks for the feedback, i have addressed your valuable feedback, please do review.

Will do a proper review after comments, no blocker atm

[Copilot]

Pull request overview

Updates KubernetesPodTrigger to perform pod deletion on user-initiated cancellation via BaseTrigger.on_kill() (Airflow 3.3+), and avoids deleting pods during triggerer restarts/redistribution by making cleanup() a no-op on 3.3+.

Changes:

• Add KubernetesPodTrigger.on_kill() to delete pods on user kills (guarded by AIRFLOW_V_3_3_PLUS).
• Update cleanup() to skip pod deletion on Airflow 3.3+ while keeping the legacy safe_to_cancel() behavior for older Airflow versions.
• Update unit tests to assert on_kill() behavior (and legacy cleanup() behavior for Airflow < 3.3).

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
providers/cncf/kubernetes/src/airflow/providers/cncf/kubernetes/triggers/pod.py	Adds on_kill() and gates pod deletion away from cleanup() on Airflow 3.3+ to prevent restart-triggered deletion.
providers/cncf/kubernetes/src/airflow/providers/cncf/kubernetes/version_compat.py	Introduces AIRFLOW_V_3_3_PLUS for provider-side feature gating.
providers/cncf/kubernetes/tests/unit/cncf/kubernetes/triggers/test_pod.py	Migrates/extends tests to validate on_kill() on 3.3+ and legacy cleanup() behavior on < 3.3.

[potiuk]

@raushanprabhakar1 — There are 2 unresolved review threads on this PR from @jscheffl. Could you either push a fix or reply in each thread explaining why the feedback doesn't apply? Once you believe the feedback is addressed, mark the thread as resolved so the reviewer isn't re-pinged needlessly. Thanks!

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[jscheffl]

Looks good for me. Second pair of eyes would be good.

@raushanprabhakar1 please run prek run -a ruff and commit changes to fix fails in static checks.

[raushanprabhakar1]

Hi @jscheffl , fixed the lint issues. Thanks

[amoghrajesh]

I will take a look too

[amoghrajesh]

Just one comment or LGTM

[boring-cyborg]

Awesome work, congrats on your first merged pull request! You are invited to check our Issue Tracker for additional contributions.