kube-state-metrics feat: Replace endpoints with endpointslices as default resource

What this PR does / why we need it: BREAKING CHANGE: endpoints are not a default resource anymore and metrics need to be replaced with endpointslices' metrics.

https://kubernetes.io/blog/2025/04/23/kubernetes-v1-33-release/#deprecation-of-the-stable-endpoints-api.

How does this change affect the cardinality of KSM: (increases, decreases or does not change cardinality) None Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged): Fixes #

Apr 23 '25 19:04 mrueg

/triage accepted cc @rexagod

May 01 '25 16:05 richabanker

I see, this moves endpoints out of the default set of resources for which we generate metrics for, and users will need to use the --resources flag to re-enable it. While that makes sense, I'd suggest a couple of releases indicating this (in the change-log, at runtime if endpoints are present in --resources, etc.) to warn users.

It'd additionally make sense to put this behind a flag, and enable it by default once the deprecation deadline hits. This way, users can start opt-ing into the feature before it's dropped.

May 07 '25 20:05 rexagod

/lgtm

/hold

Feel free to unhold

Jul 11 '25 23:07 CatherineF-dev

/hold cancel since v2.17.0 is released which includes a Note that its the last release with endpoints resource enabled by default.

@rexagod @CatherineF-dev @dgrisonnet can I get a review here again? Thanks!

Sep 02 '25 09:09 mrueg

@rexagod @CatherineF-dev can I get a review for this?

Sep 15 '25 09:09 mrueg

@rexagod @CatherineF-dev @dgrisonnet can I get another review here? I would like to get this change in for the next release.

Sep 29 '25 10:09 mrueg

Can this get reviewed please, it spams a load of warnings in our clusters now that we'd want to get cleaned up before upgrading EKS.

Oct 20 '25 10:10 andy-townsend

/lgtm /hold Users can still use endpoint if they add it back. Feel free to unhold

Dec 03 '25 18:12 CatherineF-dev

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: CatherineF-dev, mrueg

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

~~OWNERS~~ [CatherineF-dev,mrueg]

Approvers can indicate their approval by writing /approve in a comment Approvers can cancel approval by writing /approve cancel in a comment

Dec 03 '25 18:12 k8s-ci-robot

/hold cancel

thanks for the review @CatherineF-dev

Dec 03 '25 20:12 mrueg