Add snapshot back to queue

pkg/common-controller/snapshot_controller_base.go

@@ -207,10 +207,13 @@ func (ctrl *csiSnapshotCommonController) snapshotWorker() {
 			newSnapshot, err := ctrl.checkAndUpdateSnapshotClass(snapshot)
 			if err == nil {
 				klog.V(5).Infof("passed checkAndUpdateSnapshotClass for snapshot %q", key)
-				ctrl.updateSnapshot(newSnapshot)
+				err = ctrl.updateSnapshot(newSnapshot)
 			}
+			if err != nil {
+				ctrl.snapshotQueue.AddRateLimited(key)
 				return false
 			}
+		}
 		if err != nil && !errors.IsNotFound(err) {
 			klog.V(2).Infof("error getting snapshot %q from informer: %v", key, err)
 			return false
@@ -340,7 +343,7 @@ func (ctrl *csiSnapshotCommonController) checkAndUpdateSnapshotClass(snapshot *c
 
 // updateSnapshot runs in worker thread and handles "snapshot added",
 // "snapshot updated" and "periodic sync" events.
-func (ctrl *csiSnapshotCommonController) updateSnapshot(snapshot *crdv1.VolumeSnapshot) {
+func (ctrl *csiSnapshotCommonController) updateSnapshot(snapshot *crdv1.VolumeSnapshot) error {
 	// Store the new snapshot version in the cache and do not process it if this is
 	// an old version.
 	klog.V(5).Infof("updateSnapshot %q", utils.SnapshotKey(snapshot))
@@ -349,7 +352,7 @@ func (ctrl *csiSnapshotCommonController) updateSnapshot(snapshot *crdv1.VolumeSn
 		klog.Errorf("%v", err)
 	}
 	if !newSnapshot {
-		return
+		return nil
 	}
 	err = ctrl.syncSnapshot(snapshot)
 	if err != nil {
@@ -359,8 +362,10 @@ func (ctrl *csiSnapshotCommonController) updateSnapshot(snapshot *crdv1.VolumeSn
 			klog.V(3).Infof("could not sync claim %q: %+v", utils.SnapshotKey(snapshot), err)
 		} else {
 			klog.Errorf("could not sync volume %q: %+v", utils.SnapshotKey(snapshot), err)
+			return err
 		}
 	}
+	return nil
 }
 
 // updateContent runs in worker thread and handles "content added",