If BIA return updateObj with SkipFromBackupAnnotation, treat it as skip the resource from backup.

Signed-off-by: Xun Jiang <xun.jiang@broadcom.com>

changelogs/unreleased/9547-blackpiglet

@@ -0,0 +1 @@
+If BIA return updateObj with SkipFromBackupAnnotation, treat it as skip the resource from backup.

pkg/apis/velero/v1/labels_annotations.go

@@ -102,6 +102,15 @@ const (
 	// even if the resource contains a matching selector label.
 	ExcludeFromBackupLabel = "velero.io/exclude-from-backup"
 
+	// SkipFromBackupAnnotation is the annotation used by internal BackupItemActions
+	// to indicate that a resource should be skipped from backup,
+	// even if it doesn't have the ExcludeFromBackupLabel.
+	// This is used in cases where we want to skip backup of a resource based on some logic in a plugin.
+	//
+	// Notice: SkipFromBackupAnnotation's priority is higher than MustIncludeAdditionalItemAnnotation.
+	// If SkipFromBackupAnnotation is set, the resource will be skipped even if MustIncludeAdditionalItemAnnotation is set.
+	SkipFromBackupAnnotation = "velero.io/skip-from-backup"
+
 	// defaultVGSLabelKey is the default label key used to group PVCs under a VolumeGroupSnapshot
 	DefaultVGSLabelKey = "velero.io/volume-group"
 

pkg/backup/item_backupper.go

@@ -244,6 +244,12 @@ func (ib *itemBackupper) backupItemInternal(logger logrus.FieldLogger, obj runti
 		return false, itemFiles, kubeerrs.NewAggregate(backupErrs)
 	}
 
+	// If err is nil and updatedObj is nil, it means the item is skipped by plugin action,
+	// we should return here to avoid backing up the item, and avoid potential NPE in the following code.
+	if updatedObj == nil {
+		return false, itemFiles, nil
+	}
+
 	itemFiles = append(itemFiles, additionalItemFiles...)
 	obj = updatedObj
 	if metadata, err = meta.Accessor(obj); err != nil {
@@ -398,6 +404,13 @@ func (ib *itemBackupper) executeActions(
 		}
 
 		u := &unstructured.Unstructured{Object: updatedItem.UnstructuredContent()}
+
+		if _, ok := u.GetAnnotations()[velerov1api.SkipFromBackupAnnotation]; ok {
+			log.Infof("Resource (groupResource=%s, namespace=%s, name=%s) is skipped from backup by action %s.",
+				groupResource.String(), namespace, name, actionName)
+			return nil, itemFiles, nil
+		}
+
 		if actionName == csiBIAPluginName {
 			if additionalItemIdentifiers == nil && u.GetAnnotations()[velerov1api.SkippedNoCSIPVAnnotation] == "true" {
 				// snapshot was skipped by CSI plugin