Merge pull request #7022 from markturansky/ns_controller_indempotent

Made NamespaceManager.Run idempotent and added graceful shutdown

pkg/namespace/namespace_controller.go

@@ -63,14 +63,24 @@ func NewNamespaceManager(kubeClient client.Interface, resyncPeriod time.Duration
 
 	return &NamespaceManager{
 		controller: controller,
-		StopEverything: make(chan struct{}),
 	}
 }
 
 // Run begins observing the system.  It starts a goroutine and returns immediately.
 func (nm *NamespaceManager) Run() {
+	if nm.StopEverything == nil {
+		nm.StopEverything = make(chan struct{})
 		go nm.controller.Run(nm.StopEverything)
 	}
+}
+
+// Stop gracefully shutsdown this controller
+func (nm *NamespaceManager) Stop() {
+	if nm.StopEverything != nil {
+		close(nm.StopEverything)
+		nm.StopEverything = nil
+	}
+}
 
 // finalized returns true if the spec.finalizers is empty list
 func finalized(namespace api.Namespace) bool {

pkg/namespace/namespace_controller_test.go

@@ -18,8 +18,10 @@ package namespace
 
 import (
 	"testing"
+	"time"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api/latest"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/client/testclient"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
 )
@@ -131,3 +133,25 @@ func TestSyncNamespaceThatIsActive(t *testing.T) {
 		t.Errorf("Expected no action from controller, but got: %v", actionSet)
 	}
 }
+
+func TestRunStop(t *testing.T) {
+	o := testclient.NewObjects(api.Scheme)
+	client := &testclient.Fake{ReactFn: testclient.ObjectReaction(o, latest.RESTMapper)}
+	nsMgr := NewNamespaceManager(client, 1*time.Second)
+
+	if nsMgr.StopEverything != nil {
+		t.Errorf("Non-running manager should not have a stop channel.  Got %v", nsMgr.StopEverything)
+	}
+
+	nsMgr.Run()
+
+	if nsMgr.StopEverything == nil {
+		t.Errorf("Running manager should have a stop channel.  Got nil")
+	}
+
+	nsMgr.Stop()
+
+	if nsMgr.StopEverything != nil {
+		t.Errorf("Non-running manager should not have a stop channel.  Got %v", nsMgr.StopEverything)
+	}
+}