chore(backport release-0.8): fix(kubeclient): retry patch on conflict (…

…#2516)

internal/kubeclient/patch.go

@@ -10,6 +10,7 @@ import (
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/client-go/util/retry"
 	"sigs.k8s.io/controller-runtime/pkg/client"
 )
 
@@ -83,41 +84,47 @@ type UnstructuredPatchFn func(src, dest unstructured.Unstructured) error
 func PatchUnstructured(ctx context.Context, c client.Client, obj ObjectWithKind, modify UnstructuredPatchFn) error {
 	destObj := unstructured.Unstructured{}
 	destObj.SetGroupVersionKind(obj.GroupVersionKind())
-	if err := c.Get(ctx, client.ObjectKeyFromObject(obj), &destObj); err != nil {
-		return fmt.Errorf(
-			"unable to get unstructured object for %s %q in namespace %q: %w",
-			destObj.GroupVersionKind().Kind, obj.GetName(), obj.GetNamespace(), err,
-		)
-	}
-
-	// Create a patch for the unstructured object.
-	//
-	// As we expect the object to be modified by the callback, while it may
-	// also simultaneously be modified by other clients (e.g. someone updating
-	// the object via `kubectl`), we use an optimistic lock to ensure that we
-	// only apply the patch if the object has not been modified since we
-	// fetched it.
-	patch := client.MergeFromWithOptions(destObj.DeepCopy(), client.MergeFromWithOptimisticLock{})
-
-	// Convert the typed object to an unstructured object.
-	srcObj, err := runtime.DefaultUnstructuredConverter.ToUnstructured(obj)
-	if err != nil {
-		return fmt.Errorf("could not convert typed source object to unstructured object: %w", err)
-	}
-	srcApp := unstructured.Unstructured{Object: srcObj}
 
-	// Apply modifications to the unstructured object.
-	if err = modify(srcApp, destObj); err != nil {
-		return fmt.Errorf("failed to apply modifications to unstructured object: %w", err)
-	}
-
-	// Issue the patch to the unstructured object.
-	if err = c.Patch(ctx, &destObj, patch); err != nil {
-		return fmt.Errorf("failed to patch the object: %w", err)
+	if err := retry.RetryOnConflict(retry.DefaultRetry, func() error {
+		if err := c.Get(ctx, client.ObjectKeyFromObject(obj), &destObj); err != nil {
+			return fmt.Errorf(
+				"unable to get unstructured object for %s %q in namespace %q: %w",
+				destObj.GroupVersionKind().Kind, obj.GetName(), obj.GetNamespace(), err,
+			)
+		}
+
+		// Create a patch for the unstructured object.
+		//
+		// As we expect the object to be modified by the callback, while it may
+		// also simultaneously be modified by other clients (e.g. someone updating
+		// the object via `kubectl`), we use an optimistic lock to ensure that we
+		// only apply the patch if the object has not been modified since we
+		// fetched it.
+		patch := client.MergeFromWithOptions(destObj.DeepCopy(), client.MergeFromWithOptimisticLock{})
+
+		// Convert the typed object to an unstructured object.
+		srcObj, err := runtime.DefaultUnstructuredConverter.ToUnstructured(obj)
+		if err != nil {
+			return fmt.Errorf("could not convert typed source object to unstructured object: %w", err)
+		}
+		srcApp := unstructured.Unstructured{Object: srcObj}
+
+		// Apply modifications to the unstructured object.
+		if err = modify(srcApp, destObj); err != nil {
+			return fmt.Errorf("failed to apply modifications to unstructured object: %w", err)
+		}
+
+		// Issue the patch to the unstructured object.
+		if err = c.Patch(ctx, &destObj, patch); err != nil {
+			return fmt.Errorf("failed to patch the object: %w", err)
+		}
+		return nil
+	}); err != nil {
+		return err
 	}
 
 	// Convert the unstructured object back to the typed object.
-	if err = runtime.DefaultUnstructuredConverter.FromUnstructured(destObj.Object, obj); err != nil {
+	if err := runtime.DefaultUnstructuredConverter.FromUnstructured(destObj.Object, obj); err != nil {
 		return fmt.Errorf("error converting unstructured object to typed object: %w", err)
 	}