layer1: prepare managed namespace watchers

pkg/utils/namespace_manager.go

@@ -109,6 +109,12 @@ func NewWatcherNamespaceManager(ctx context.Context, namespaces []string, source
 	return manager, err
 }
 
+func PrepareManagedNamespaceWatcher(ctx context.Context, logger *zap.Logger, component string, namespaces []string, removalStrategy NamespaceRemovalStrategy, subscriber NamespaceSubscriber) (NamespaceManager, k8sCache.ResourceEventHandlerFuncs, error) {
+	manager, err := NewWatcherNamespaceManager(ctx, namespaces, NamespaceSourceEnv, time.Now().UTC(), subscriber)
+	handlers := NewNamespaceWatcherEventHandlers(ctx, logger, component, manager, removalStrategy)
+	return manager, handlers, err
+}
+
 func NamespaceBecameUnmanaged(oldNamespace *corev1.Namespace, newNamespace *corev1.Namespace) bool {
 	if oldNamespace == nil || newNamespace == nil {
 		return false

pkg/utils/namespace_manager_test.go

@@ -429,6 +429,25 @@ func TestNewNamespaceWatcherEventHandlers(t *testing.T) {
 	}
 }
 
+func TestPrepareManagedNamespaceWatcher(t *testing.T) {
+	router := &testNamespaceSubscriber{name: "router"}
+	logger := zap.NewNop()
+	manager, handlers, err := PrepareManagedNamespaceWatcher(context.Background(), logger, "router.NSWatcher", []string{"tenant-a"}, NamespaceRemovalStrategyTrackOnly, router)
+	if err != nil {
+		t.Fatalf("expected watcher preparation success: %v", err)
+	}
+	if !reflect.DeepEqual([]string{"tenant-a"}, manager.Snapshot()) {
+		t.Fatalf("expected watcher manager snapshot to contain bootstrapped namespace")
+	}
+	namespace := &corev1.Namespace{}
+	namespace.Name = "tenant-a"
+	namespace.Labels = map[string]string{ManagedNamespaceLabelKey: ManagedNamespaceLabelValue}
+	handlers.UpdateFunc(namespace, namespace)
+	if router.addCalls != 1 || router.resyncCalls != 1 {
+		t.Fatalf("expected bootstrap add and handler resync calls")
+	}
+}
+
 func TestNamespaceManagerDispatchAdd(t *testing.T) {
 	manager := NewNamespaceManager()
 	manager.Upsert(NamespaceEvent{Type: NamespaceEventAdd, Name: "tenant-a", Source: NamespaceSourceWatcher})