Merge pull request kubernetes-sigs#1345 from charith-elastic/fix/source-dest-lock

🐛 Prevent source.Channel from shutting down immediately

Author: k8s-ci-robot

pkg/internal/controller/controller.go

@@ -163,9 +163,7 @@ func (c *Controller) Start(ctx context.Context) error {
 		for _, watch := range c.startWatches {
 			c.Log.Info("Starting EventSource", "source", watch.src)
 
-			watchStartCtx, cancel := context.WithTimeout(ctx, c.CacheSyncTimeout)
-			defer cancel()
-			if err := watch.src.Start(watchStartCtx, watch.handler, c.Queue, watch.predicates...); err != nil {
+			if err := watch.src.Start(ctx, watch.handler, c.Queue, watch.predicates...); err != nil {
 				return err
 			}
 		}
@@ -179,15 +177,21 @@ func (c *Controller) Start(ctx context.Context) error {
 				continue
 			}
 
-			// use a context with timeout for launching sources and syncing caches.
-			sourceStartCtx, cancel := context.WithTimeout(ctx, c.CacheSyncTimeout)
-			defer cancel()
+			if err := func() error {
+				// use a context with timeout for launching sources and syncing caches.
+				sourceStartCtx, cancel := context.WithTimeout(ctx, c.CacheSyncTimeout)
+				defer cancel()
+
+				// WaitForSync waits for a definitive timeout, and returns if there
+				// is an error or a timeout
+				if err := syncingSource.WaitForSync(sourceStartCtx); err != nil {
+					err := fmt.Errorf("failed to wait for %s caches to sync: %w", c.Name, err)
+					c.Log.Error(err, "Could not wait for Cache to sync")
+					return err
+				}
 
-			// WaitForSync waits for a definitive timeout, and returns if there
-			// is an error or a timeout
-			if err := syncingSource.WaitForSync(sourceStartCtx); err != nil {
-				err := fmt.Errorf("failed to wait for %s caches to sync: %w", c.Name, err)
-				c.Log.Error(err, "Could not wait for Cache to sync")
+				return nil
+			}(); err != nil {
 				return err
 			}
 		}

pkg/source/source.go

@@ -215,7 +215,10 @@ func (cs *Channel) Start(
 	}
 
 	dst := make(chan event.GenericEvent, cs.DestBufferSize)
+
+	cs.destLock.Lock()
 	cs.dest = append(cs.dest, dst)
+	cs.destLock.Unlock()
 
 	cs.once.Do(func() {
 		// Distribute GenericEvents to all EventHandler / Queue pairs Watching this source
@@ -238,9 +241,6 @@ func (cs *Channel) Start(
 		}
 	}()
 
-	cs.destLock.Lock()
-	defer cs.destLock.Unlock()
-
 	return nil
 }