fix panic when calling ToUnstructured on nil metav1.Time

[com6056]

Currently, when calling ToUnstructured on a metav1.Time that is a nil pointer, you get a panic:

panic: value method k8s.io/apimachinery/pkg/apis/meta/v1.Time.ToUnstructured called using nil *Time pointer

goroutine 1 [running]:
k8s.io/apimachinery/pkg/apis/meta/v1.(*Time).ToUnstructured(0x100000001?)
	<autogenerated>:1 +0x48
sigs.k8s.io/structured-merge-diff/v4/value.TypeReflectCacheEntry.ToUnstructured({0x1, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0, {0x0, 0x0, 0x0}}, ...)
	external/io_k8s_sigs_structured_merge_diff_v4/value/reflectcache.go:192 +0x658
k8s.io/apimachinery/pkg/runtime.toUnstructured({0x108eaaf80?, 0x14001065390?, 0x1?}, {0x108686960?, 0x14003e181b0?, 0x98?})
	external/io_k8s_apimachinery/pkg/runtime/converter.go:655 +0x6d4
k8s.io/apimachinery/pkg/runtime.structToUnstructured({0x108a15600?, 0x14001065378?, 0x1?}, {0x108686960?, 0x14003e18150?, 0x104d118f8?})
	external/io_k8s_apimachinery/pkg/runtime/converter.go:843 +0x764
k8s.io/apimachinery/pkg/runtime.toUnstructured({0x108a15600?, 0x14001065378?, 0x3?}, {0x108686960?, 0x14003e18150?, 0x98?})
	external/io_k8s_apimachinery/pkg/runtime/converter.go:692 +0x628
k8s.io/apimachinery/pkg/runtime.structToUnstructured({0x108b1ca20?, 0x14001065008?, 0x8?}, {0x10870bce0?, 0x14001783600?, 0x104d118f8?})
	external/io_k8s_apimachinery/pkg/runtime/converter.go:843 +0x764
k8s.io/apimachinery/pkg/runtime.toUnstructured({0x108b1ca20?, 0x14001065008?, 0x10823aa40?}, {0x10870bce0?, 0x14001783600?, 0x8?})
	external/io_k8s_apimachinery/pkg/runtime/converter.go:692 +0x628
k8s.io/apimachinery/pkg/runtime.(*unstructuredConverter).ToUnstructured(0x10b8d9c80, {0x108e80880, 0x14001065008})
	external/io_k8s_apimachinery/pkg/runtime/converter.go:586 +0x250
...

This moves the nil pointer check up to before we check if there is a custom converter so that we don't attempt to call ToUnstructured on a nil pointer which triggers the panic.

Related issues:

• Panic in TypeReflectCacheEntry.ToUnstructured if a pointer-typed field without omitempty specifier is attempted to be converted #229
• Converting an operator group object to an unstructured object causes a panic operator-framework/api#269

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[k8s-ci-robot]

Hi @com6056. Thanks for your PR.

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[dprotaso]

/ok-to-test
/assign @jpbetz

[com6056]

@jpbetz anything I can do to help get this reviewed? Let me know if I can provide any additional context! 🙏

[olte36]

It seems the PR fixes metav1.Duration too, so it would be nice to have the fix, thanks @com6056

[jpbetz]

ack, i'll try to get to this

[jpbetz]

/lgtm
/approve
Thanks for the fix!

[dprotaso]

Looks like the owner file is out of date - @apelisse is the only approved

…

On Wed, May 29, 2024 at 17:21 Kubernetes Prow Robot < ***@***.***> wrote: [APPROVALNOTIFIER] This PR is *NOT APPROVED* This pull-request has been approved by: *com6056 <#258#>*, *jpbetz <#258 (comment)>* *Once this PR has been reviewed and has the lgtm label*, please assign apelisse <https://github.com/apelisse> for approval. For more information see the Kubernetes Code Review Process <https://git.k8s.io/community/contributors/guide/owners.md#the-code-review-process> . The full list of commands accepted by this bot can be found here <https://go.k8s.io/bot-commands?repo=kubernetes-sigs%2Fstructured-merge-diff> . Needs approval from an approver in each of these files: - *OWNERS <https://github.com/kubernetes-sigs/structured-merge-diff/blob/master/OWNERS>* Approvers can indicate their approval by writing /approve in a comment Approvers can cancel approval by writing /approve cancel in a comment — Reply to this email directly, view it on GitHub <#258 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAAERASG6WD4BZLFZN5RSD3ZEZBF3AVCNFSM6AAAAABHXQIVHWVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDCMZYGI4DIMJQG4> . You are receiving this because you commented.Message ID: ***@***.***>

[apelisse]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: apelisse, com6056, jpbetz

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Needs approval from an approver in each of these files:

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