Merge pull request #116297 from p0lyn0mial/upstream-reflector-list-n-watch-refactor

reflector: extract watch and startResyncAsync methods

staging/src/k8s.io/client-go/tools/cache/reflector.go

@@ -323,31 +323,40 @@ func (r *Reflector) ListAndWatch(stopCh <-chan struct{}) error {
 	resyncerrc := make(chan error, 1)
 	cancelCh := make(chan struct{})
 	defer close(cancelCh)
-	go func() {
-		resyncCh, cleanup := r.resyncChan()
-		defer func() {
-			cleanup() // Call the last one written into cleanup
-		}()
-		for {
-			select {
-			case <-resyncCh:
-			case <-stopCh:
-				return
-			case <-cancelCh:
-				return
-			}
-			if r.ShouldResync == nil || r.ShouldResync() {
-				klog.V(4).Infof("%s: forcing resync", r.name)
-				if err := r.store.Resync(); err != nil {
-					resyncerrc <- err
-					return
-				}
-			}
-			cleanup()
-			resyncCh, cleanup = r.resyncChan()
-		}
-	}()
+	go r.startResync(stopCh, cancelCh, resyncerrc)
+	return r.watch(stopCh, resyncerrc)
+}
 
+// startResync periodically calls r.store.Resync() method.
+// Note that this method is blocking and should be
+// called in a separate goroutine.
+func (r *Reflector) startResync(stopCh <-chan struct{}, cancelCh <-chan struct{}, resyncerrc chan error) {
+	resyncCh, cleanup := r.resyncChan()
+	defer func() {
+		cleanup() // Call the last one written into cleanup
+	}()
+	for {
+		select {
+		case <-resyncCh:
+		case <-stopCh:
+			return
+		case <-cancelCh:
+			return
+		}
+		if r.ShouldResync == nil || r.ShouldResync() {
+			klog.V(4).Infof("%s: forcing resync", r.name)
+			if err := r.store.Resync(); err != nil {
+				resyncerrc <- err
+				return
+			}
+		}
+		cleanup()
+		resyncCh, cleanup = r.resyncChan()
+	}
+}
+
+// watch simply starts a watch request with the server.
+func (r *Reflector) watch(stopCh <-chan struct{}, resyncerrc chan error) error {
 	retry := NewRetryWithDeadline(r.MaxInternalErrorRetryDuration, time.Minute, apierrors.IsInternalError, r.clock)
 	for {
 		// give the stopCh a chance to stop the loop, even in case of continue statements further down on errors