Fix delete dataupload datadownload failure when Velero uninstall

[qiuming-best]

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Fixes #(issue)
#6687

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[codecov]

Codecov Report

Merging #6689 (7f3b7fe) into main (3e61386) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main    #6689   +/-   ##
=======================================
  Coverage   60.36%   60.36%           
=======================================
  Files         242      242           
  Lines       25982    25982           
=======================================
  Hits        15683    15683           
  Misses       9196     9196           
  Partials     1103     1103           

Files Changed	Coverage Δ
pkg/controller/data_download_controller.go	75.18% <100.00%> (ø)
pkg/controller/data_upload_controller.go	68.25% <100.00%> (ø)

[blackpiglet]

Creating each function for Restore, DataUpload, and DataDownload seems a bit redundant.
Could we use a unified function for all three resources?

[qiuming-best]

I've used the reflect mechanism in Golang to restructure it.

[qiuming-best]

For this function, I try to use reflect in Golang, It always panics with panic: interface conversion: v2alpha1.DataUpload is not client.Object: missing method DeepCopyObject. I could not figure it out in a short time. so I keep it with redundancy codes

func removeFinalizer(ctx context.Context, kbClient kbclient.Client, namespace string, resourceList kbclient.ObjectList, finalizer string) error {
	listOptions := &kbclient.ListOptions{Namespace: namespace}
	if err := kbClient.List(ctx, resourceList, listOptions); err != nil {
		return errors.Wrap(err, fmt.Sprintf("Error getting resources of type %T during force deletion", resourceList))
	}

	itemsValue := reflect.ValueOf(resourceList).Elem().FieldByName("Items")
	for i := 0; i < itemsValue.Len(); i++ {
		item := itemsValue.Index(i).Interface().(kbclient.Object)
		if controllerutil.ContainsFinalizer(item, finalizer) {
			update := item.DeepCopyObject().(kbclient.Object)
			original := item.DeepCopyObject().(kbclient.Object)
			controllerutil.RemoveFinalizer(update, finalizer)
			if err := kubeutil.PatchResource(original, update, kbClient); err != nil {
				return errors.Wrap(err, fmt.Sprintf("Error removing finalizer %q during force deletion", finalizer))
			}
		}
	}
	return nil
}

[shawn-hurley]

If our type does not conform to that interface, I think this could be a larger problem for anyone working with these API's. I think to fix, you have to run the controller-tools tool to generate these methods for the API.

https://book.kubebuilder.io/reference/markers/object.html

[qiuming-best]

Thanks for your comment @shawn-hurley, I've fixed it.
I should not covert interface into kbclient.Objecttype in item := itemsValue.Index(i).Interface().(kbclient.Object)

As here is the definition of DatauploadList

type DataUploadList struct {
    metav1.TypeMeta `json:",inline"`

    // +optional
    metav1.ListMeta `json:"metadata,omitempty"`

    Items []DataUpload `json:"items"`
}

And we have the DeepCopyObject function for *DataUpload type not DataUpload:

func (in *DataUpload) DeepCopyObject() runtime.Object {
	if c := in.DeepCopy(); c != nil {
		return c
	}
	return nil
}

The Item in DataUploadList is DataUpload but not *DataUpload, so it panic with v2alpha1.DataUpload is not client.Object: missing method DeepCopyObject