watcher: Clean up properly on exiting event loop

logs/pod_watcher.go

@@ -100,7 +100,7 @@ const tickerInterval = time.Millisecond * 250
 
 // Close terminates the PodWatcher.
 func (pw *PodWatcher) Close() {
-	pw.closeChan <- struct{}{}
+	close(pw.closeChan)
 }
 
 func (pw *PodWatcher) watchPods(ctx context.Context, wg *sync.WaitGroup) error {

logs/watcher.go

@@ -54,6 +54,7 @@ type Watcher struct {
 	podSelector    labels.Selector
 	podWatcher     PodWatcherInterface
 	podWatcherFunc PodWatcherFunc
+	closeChan      chan struct{}
 	errChan        chan error
 	dst            io.Writer
 	logger         *log.Logger
@@ -65,14 +66,24 @@ func NewWatcher(params WatcherParams, client KubernetesClient, podWatcherFunc Po
 		params:         params,
 		client:         client,
 		podWatcherFunc: podWatcherFunc,
+		closeChan:      make(chan struct{}),
 		errChan:        make(chan error),
 		dst:            dst,
 		logger:         logger,
 	}
 }
 
+// Close blocks until any actively monitored resource has been released, and
+// exits.
+func (w *Watcher) Close() {
+	close(w.closeChan)
+}
+
 // Watch watches a deployment.
 func (w *Watcher) Watch(ctx context.Context) error {
+	// ensure any actively monitored resource is cleaned up on exit.
+	defer w.removeDeployment()
+
 	ns := w.params.Namespace
 	if ns == "" {
 		ns = corev1.NamespaceDefault
@@ -127,6 +138,8 @@ func (w *Watcher) Watch(ctx context.Context) error {
 		// errChan is never closed.
 		case err := <-w.errChan:
 			return err
+		case <-w.closeChan:
+			return nil
 		case <-ctx.Done():
 			return ctx.Err()
 		}