🐛 fix(controllerutil): avoid panic when the MutateFn is nil

[0xff-dev]

I checked the CreateOrPatch function and it checked if MutateFn is nil, but CreateOrUpdate did not check.

Or is it possible to modify the mutate function directly and execute MutateFn only when MutateFn is not nil?

controller-runtime/pkg/controller/controllerutil/controllerutil.go

Line 425 in 5dcea7e

func mutate(f MutateFn, key client.ObjectKey, obj client.Object) error {

[k8s-ci-robot]

Hi @0xff-dev. Thanks for your PR.

I'm waiting for a kubernetes-sigs 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.

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: 0xff-dev
Once this PR has been reviewed and has the lgtm label, please assign alvaroaleman for approval. For more information see the Kubernetes Code Review Process.

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

Needs approval from an approver in each of these files:

• OWNERS

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

[troy0820]

Don't we want this to panic because the caller must apply a mutatefn? This function is supposed to be called regardless and adding the nil check suggests that we can perform this without this function being called.

[0xff-dev]

Don't we want this to panic because the caller must apply a mutatefn? This function is supposed to be called regardless and adding the nil check suggests that we can perform this without this function being called.

You're right, by the function comment it states that the function would have been called anyway, but CreateOrPatch states the same thing, in the code it does a check. I think that even though the comment states the behavior of the function, it's still important to prevent special input from the user.

[troy0820]

You're right, by the function comment it states that the function would have been called anyway, but CreateOrPatch states the same thing, in the code it does a check. I think that even though the comment states the behavior of the function, it's still important to prevent special input from the user.

Fair point, I know the functions exhibit different behavior (Patching subresource doesn't happen in CreateOrUpdate), and may be a reason to make sure that the object doesn't. I can't speak to this difference in behavior but will agree with your point.

/ok-to-test