fix: include node events with null involvedObject.uid in describe output

[vigneshakaviki]

What type of PR is this?

/kind bug
/sig cli

What this PR does / why we need it

kubectl describe node omits events where involvedObject.uid is unset/null. This happens with kubelet-emitted node status events on some clusters (e.g. EKS), where kubelet creates events with involvedObject.uid: null but valid involvedObject.kind=Node and involvedObject.name=<node>.

Currently NodeDescriber.Describe() searches for events using two UIDs:

1. The node's real UID (for controller events)
2. The node name as UID (for kubelet events using the name workaround)

Neither matches events where involvedObject.uid is null/empty.

How does this PR fix it

Adds a third search with empty UID (matching by kind+name only) and deduplicates the merged results using event UIDs to avoid showing duplicate entries.

Verified end-to-end on a local minikube cluster

Stock kubectl — event with null UID is missing from describe node output.
Patched kubectl — event with null UID correctly appears.

See detailed test results in kubernetes/kubectl/pull/1840 (closed per @soltysh's direction to open here instead).

Which issue(s) this PR fixes

Ref: kubernetes/kubectl/issues/1838

Does this PR introduce a user-facing change?

Fixed kubectl describe node to show events where involvedObject.uid is null, such as kubelet-emitted node status events on some clusters.

[k8s-ci-robot]

Please note that we're already in Code Freeze for the upcoming v1.36.0 release.

Adding the milestone to this PR is strictly prohibited without proper approval. If this PR needs to be included in the v1.36.0 release:

1. Technical review: get the PR reviewed and approved as usual (/lgtm and /approve)
2. Inclusion in release: ping @sig-release-leads on the #sig-release Slack channel and suggest to add the v1.36.0 milestone to the PR

---

We're also in Test Freeze for the release-1.36 branch. This means every merged PR will be automatically fast-forwarded via the periodic ci-fast-forward job to the release branch of the upcoming v1.36.0 release.

Fast forwards are scheduled to happen every 6 hours, whereas the most recent run was: Mon Apr 13 20:20:51 UTC 2026.

[k8s-ci-robot]

This issue is currently awaiting triage.

If a SIG or subproject determines this is a relevant issue, they will accept it by applying the triage/accepted label and provide further guidance.

The triage/accepted label can be added by org members by writing /triage accepted in a comment.

Details

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[k8s-ci-robot]

Welcome @vigneshakaviki!

It looks like this is your first PR to kubernetes/kubernetes 🎉. Please refer to our pull request process documentation to help your PR have a smooth ride to approval.

You will be prompted by a bot to use commands during the review process. Do not be afraid to follow the prompts! It is okay to experiment. Here is the bot commands documentation.

You can also check if kubernetes/kubernetes has its own contribution guidelines.

You may want to refer to our testing guide if you run into trouble with your tests not passing.

If you are having difficulty getting your pull request seen, please follow the recommended escalation practices. Also, for tips and tricks in the contribution process you may want to read the Kubernetes contributor cheat sheet. We want to make sure your contribution gets all the attention it needs!

Thank you, and welcome to Kubernetes. 😃

[k8s-ci-robot]

Hi @vigneshakaviki. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work.

Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

Details

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: vigneshakaviki
Once this PR has been reviewed and has the lgtm label, please assign seans3 for approval. For more information see the Code Review Process.

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

Details

Needs approval from an approver in each of these files:

• staging/src/k8s.io/kubectl/OWNERS

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