layer1: share managed namespace watcher startup

pkg/executor/multitenant/ns_watcher.go

@@ -65,11 +65,7 @@ import (
 	"time"
 
 	"go.uber.org/zap"
-	corev1 "k8s.io/api/core/v1"
-	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	k8sInformers "k8s.io/client-go/informers"
 	"k8s.io/client-go/kubernetes"
-	k8sCache "k8s.io/client-go/tools/cache"
 
 	fv1 "github.com/fission/fission/pkg/apis/core/v1"
 	"github.com/fission/fission/pkg/executor/executortype"
@@ -96,30 +92,7 @@ func StartNSWatcher(
 	if err != nil {
 		logger.Error("multitenant.NSWatcher: BootstrapAndDispatch failed", zap.Error(err))
 	}
-
-	// Use a label-filtered informer so only Namespaces with our label are delivered.
-	// The resync period of 30m is standard for Fission informers — it re-lists to recover
-	// from any missed events, but normal operation is purely event-driven (no ticking).
-	factory := k8sInformers.NewSharedInformerFactoryWithOptions(
-		kubernetesClient,
-		30*time.Minute,
-		k8sInformers.WithTweakListOptions(func(opts *metav1.ListOptions) {
-			opts.LabelSelector = utils.ManagedNamespaceLabelSelector()
-		}),
-	)
-
-	nsInformer := factory.Core().V1().Namespaces().Informer()
-
-	_, _ = nsInformer.AddEventHandler(utils.NewNamespaceWatcherEventHandlers(ctx, logger, "multitenant.NSWatcher", nsManager, utils.NamespaceRemovalStrategyTrackOnly))
-
-	mgr.Add(ctx, func(ctx context.Context) {
-		logger.Info("multitenant.NSWatcher: started", zap.String("label", utils.ManagedNamespaceLabelSelector()))
-		factory.Start(ctx.Done())
-		factory.WaitForCacheSync(ctx.Done())
-		logger.Info("multitenant.NSWatcher: cache synced — watching for new namespaces")
-		<-ctx.Done()
-		logger.Info("multitenant.NSWatcher: stopped")
-	})
+	utils.StartManagedNamespaceWatcher(ctx, logger, "multitenant.NSWatcher", kubernetesClient, mgr, utils.NewNamespaceWatcherEventHandlers(ctx, logger, "multitenant.NSWatcher", nsManager, utils.NamespaceRemovalStrategyTrackOnly))
 }
 
 // registerNamespace calls AddNamespace on every executor type for the given namespace.