fix: Panic on nodeClassRef nil dereference

[engedaam]

Fixes aws/karpenter-provider-aws#6867

Description

• As part of server side apply, we saw that the API Server will send particle objects to be converted by the conversion webhooks. The API server will send a particle objects of fields that are owned by the field manger in applying a patch https://kubernetes.io/docs/reference/using-api/server-side-apply/#field-management. This can cause out conversion webhooks trying to deference a nil point on the nodeClassRef.

How was this change tested?

• make presubmit

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[k8s-ci-robot]

Skipping CI for Draft Pull Request.
If you want CI signal for your change, please convert it to an actual PR.
You can still manually trigger a test run with /test all

[jonathan-innis]

Are we going to add testing for this case?

[engedaam]

I am planning on testing the panic of SSA as part E2E testing. But for now I added tests that validate the nil check until then.

[jonathan-innis]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: engedaam, jonathan-innis

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 [jonathan-innis]

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

[anzinchenko89]

@engedaam, could you please clarify when this fix is supposed to be released and which patch version v1.0.x is going to contain it? Thanks

[engedaam]

We don't have a release date, but should be soon. It will be included in the next patch release for v1.0.3

[archana-punia]

Hi, Is this released in 1.0.4?

[jmdeal]

Yes, it's included in the 1.0.4 release for the AWS provider (1.0.2 in this repo).