Merge pull request #4751 from bprashanth/sync_replica_count

Replication Controller syncs current replica count with api server #4429

cmd/integration/integration.go

@@ -203,9 +203,8 @@ func startComponents(manifestURL string) (apiServerURL string) {
 
 	controllerManager := replicationControllerPkg.NewReplicationManager(cl)
 
-	// Prove that controllerManager's watch works by making it not sync until after this
+	// TODO: Write an integration test for the replication controllers watch.
-	// test is over. (Hopefully we don't take 10 minutes!)
+	controllerManager.Run(1 * time.Second)
-	controllerManager.Run(10 * time.Minute)
 
 	nodeResources := &api.NodeResources{}
 

pkg/controller/replication_controller.go

@@ -196,7 +196,8 @@ func (rm *ReplicationManager) syncReplicationController(controller api.Replicati
 		return err
 	}
 	filteredList := FilterActivePods(podList.Items)
-	diff := len(filteredList) - controller.Spec.Replicas
+	activePods := len(filteredList)
+	diff := activePods - controller.Spec.Replicas
 	if diff < 0 {
 		diff *= -1
 		wait := sync.WaitGroup{}
@@ -221,6 +222,13 @@ func (rm *ReplicationManager) syncReplicationController(controller api.Replicati
 		}
 		wait.Wait()
 	}
+	if controller.Status.Replicas != activePods {
+		controller.Status.Replicas = activePods
+		_, err = rm.kubeClient.ReplicationControllers(controller.Namespace).Update(&controller)
+		if err != nil {
+			return err
+		}
+	}
 	return nil
 }
 

pkg/controller/replication_controller_test.go

@@ -68,6 +68,8 @@ func (f *FakePodControl) deletePod(namespace string, podName string) error {
 
 func newReplicationController(replicas int) api.ReplicationController {
 	return api.ReplicationController{
+		TypeMeta:   api.TypeMeta{APIVersion: testapi.Version()},
+		ObjectMeta: api.ObjectMeta{Name: "foobar", Namespace: "default", ResourceVersion: "18"},
 		Spec: api.ReplicationControllerSpec{
 			Replicas: replicas,
 			Template: &api.PodTemplateSpec{
@@ -81,8 +83,14 @@ func newReplicationController(replicas int) api.ReplicationController {
 					Containers: []api.Container{
 						{
 							Image: "foo/bar",
+							TerminationMessagePath: api.TerminationMessagePathDefault,
+							ImagePullPolicy:        api.PullIfNotPresent,
 						},
 					},
+					RestartPolicy: api.RestartPolicy{
+						Always: &api.RestartPolicyAlways{},
+					},
+					DNSPolicy: api.DNSDefault,
 					NodeSelector: map[string]string{
 						"baz": "blah",
 					},
@@ -159,23 +167,37 @@ func TestSyncReplicationControllerDeletes(t *testing.T) {
 
 func TestSyncReplicationControllerCreates(t *testing.T) {
 	body := runtime.EncodeOrDie(testapi.Codec(), newPodList(0))
-	fakeHandler := util.FakeHandler{
+	fakePodHandler := util.FakeHandler{
 		StatusCode:   200,
 		ResponseBody: string(body),
 	}
-	testServer := httptest.NewServer(&fakeHandler)
+	fakePodControl := FakePodControl{}
+
+	controller := newReplicationController(2)
+	fakeUpdateHandler := util.FakeHandler{
+		StatusCode:   200,
+		ResponseBody: runtime.EncodeOrDie(testapi.Codec(), &controller),
+		T:            t,
+	}
+
+	testServerMux := http.NewServeMux()
+	testServerMux.Handle("/api/"+testapi.Version()+"/pods/", &fakePodHandler)
+	testServerMux.Handle(fmt.Sprintf("/api/"+testapi.Version()+"/replicationControllers/%s", controller.Name), &fakeUpdateHandler)
+	testServer := httptest.NewServer(testServerMux)
 	defer testServer.Close()
 	client := client.NewOrDie(&client.Config{Host: testServer.URL, Version: testapi.Version()})
 
-	fakePodControl := FakePodControl{}
-
 	manager := NewReplicationManager(client)
 	manager.podControl = &fakePodControl
-
+	manager.syncReplicationController(controller)
-	controllerSpec := newReplicationController(2)
-
-	manager.syncReplicationController(controllerSpec)
 	validateSyncReplication(t, &fakePodControl, 2, 0)
+
+	// No Status.Replicas update expected even though 2 pods were just created,
+	// because the controller manager can't observe the pods till the next sync cycle.
+	if fakeUpdateHandler.RequestReceived != nil {
+		t.Errorf("Unexpected updates for controller via %v",
+			fakeUpdateHandler.RequestReceived.URL)
+	}
 }
 
 func TestCreateReplica(t *testing.T) {
@@ -193,33 +215,7 @@ func TestCreateReplica(t *testing.T) {
 		kubeClient: client,
 	}
 
-	controllerSpec := api.ReplicationController{
+	controllerSpec := newReplicationController(1)
-		ObjectMeta: api.ObjectMeta{
-			Name: "test",
-		},
-		Spec: api.ReplicationControllerSpec{
-			Template: &api.PodTemplateSpec{
-				ObjectMeta: api.ObjectMeta{
-					Labels: map[string]string{
-						"name":                  "foo",
-						"type":                  "production",
-						"replicationController": "test",
-					},
-				},
-				Spec: api.PodSpec{
-					Containers: []api.Container{
-						{
-							Image: "foo/bar",
-						},
-					},
-					NodeSelector: map[string]string{
-						"foo": "bar",
-					},
-				},
-			},
-		},
-	}
-
 	podControl.createReplica(ns, controllerSpec)
 
 	manifest := api.ContainerManifest{}
@@ -245,48 +241,13 @@ func TestCreateReplica(t *testing.T) {
 	}
 }
 
-func TestSynchonize(t *testing.T) {
+func TestSynchronize(t *testing.T) {
-	controllerSpec1 := api.ReplicationController{
+	controllerSpec1 := newReplicationController(4)
-		TypeMeta: api.TypeMeta{APIVersion: testapi.Version()},
+	controllerSpec2 := newReplicationController(3)
-		Spec: api.ReplicationControllerSpec{
+	controllerSpec2.Name = "bar"
-			Replicas: 4,
+	controllerSpec2.Spec.Template.ObjectMeta.Labels = map[string]string{
-			Template: &api.PodTemplateSpec{
+		"name": "bar",
-				ObjectMeta: api.ObjectMeta{
+		"type": "production",
-					Labels: map[string]string{
-						"name": "foo",
-						"type": "production",
-					},
-				},
-				Spec: api.PodSpec{
-					Containers: []api.Container{
-						{
-							Image: "foo/bar",
-						},
-					},
-				},
-			},
-		},
-	}
-	controllerSpec2 := api.ReplicationController{
-		TypeMeta: api.TypeMeta{APIVersion: testapi.Version()},
-		Spec: api.ReplicationControllerSpec{
-			Replicas: 3,
-			Template: &api.PodTemplateSpec{
-				ObjectMeta: api.ObjectMeta{
-					Labels: map[string]string{
-						"name": "bar",
-						"type": "production",
-					},
-				},
-				Spec: api.PodSpec{
-					Containers: []api.Container{
-						{
-							Image: "bar/baz",
-						},
-					},
-				},
-			},
-		},
 	}
 
 	fakeEtcd := tools.NewFakeEtcdClient(t)
@@ -339,6 +300,106 @@ func TestSynchonize(t *testing.T) {
 	validateSyncReplication(t, &fakePodControl, 7, 0)
 }
 
+func TestControllerNoReplicaUpdate(t *testing.T) {
+	// Steady state for the replication controller, no Status.Replicas updates expected
+	rc := newReplicationController(5)
+	rc.Status = api.ReplicationControllerStatus{Replicas: 5}
+	activePods := 5
+
+	body, _ := latest.Codec.Encode(newPodList(activePods))
+	fakePodHandler := util.FakeHandler{
+		StatusCode:   200,
+		ResponseBody: string(body),
+		T:            t,
+	}
+	fakeControllerHandler := util.FakeHandler{
+		StatusCode: 200,
+		ResponseBody: runtime.EncodeOrDie(latest.Codec, &api.ReplicationControllerList{
+			Items: []api.ReplicationController{rc},
+		}),
+		T: t,
+	}
+	fakeUpdateHandler := util.FakeHandler{
+		StatusCode:   200,
+		ResponseBody: runtime.EncodeOrDie(testapi.Codec(), &rc),
+		T:            t,
+	}
+
+	mux := http.NewServeMux()
+	mux.Handle("/api/"+testapi.Version()+"/pods/", &fakePodHandler)
+	mux.Handle("/api/"+testapi.Version()+"/replicationControllers/", &fakeControllerHandler)
+	mux.Handle(fmt.Sprintf("/api/"+testapi.Version()+"/replicationControllers/%s", rc.Name), &fakeUpdateHandler)
+	mux.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
+		w.WriteHeader(http.StatusNotFound)
+		t.Errorf("Unexpected request for %v", req.RequestURI)
+	})
+	testServer := httptest.NewServer(mux)
+	defer testServer.Close()
+	client := client.NewOrDie(&client.Config{Host: testServer.URL, Version: testapi.Version()})
+	manager := NewReplicationManager(client)
+	fakePodControl := FakePodControl{}
+	manager.podControl = &fakePodControl
+
+	manager.synchronize()
+
+	validateSyncReplication(t, &fakePodControl, 0, 0)
+	if fakeUpdateHandler.RequestReceived != nil {
+		t.Errorf("Unexpected updates for controller via %v",
+			fakeUpdateHandler.RequestReceived.URL)
+	}
+}
+
+func TestControllerUpdateReplicas(t *testing.T) {
+	// Insufficient number of pods in the system, and Status.Replicas is wrong;
+	// Status.Replica should update to match number of pods in system, 1 new pod should be created.
+	rc := newReplicationController(5)
+	rc.Status = api.ReplicationControllerStatus{Replicas: 2}
+	activePods := 4
+
+	body, _ := latest.Codec.Encode(newPodList(activePods))
+	fakePodHandler := util.FakeHandler{
+		StatusCode:   200,
+		ResponseBody: string(body),
+		T:            t,
+	}
+	fakeControllerHandler := util.FakeHandler{
+		StatusCode: 200,
+		ResponseBody: runtime.EncodeOrDie(latest.Codec, &api.ReplicationControllerList{
+			Items: []api.ReplicationController{rc},
+		}),
+		T: t,
+	}
+	fakeUpdateHandler := util.FakeHandler{
+		StatusCode:   200,
+		ResponseBody: runtime.EncodeOrDie(testapi.Codec(), &rc),
+		T:            t,
+	}
+
+	mux := http.NewServeMux()
+
+	mux.Handle("/api/"+testapi.Version()+"/pods/", &fakePodHandler)
+	mux.Handle("/api/"+testapi.Version()+"/replicationControllers/", &fakeControllerHandler)
+	mux.Handle(fmt.Sprintf("/api/"+testapi.Version()+"/replicationControllers/%s", rc.Name), &fakeUpdateHandler)
+	mux.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
+		w.WriteHeader(http.StatusNotFound)
+		t.Errorf("Unexpected request for %v", req.RequestURI)
+	})
+	testServer := httptest.NewServer(mux)
+	defer testServer.Close()
+	client := client.NewOrDie(&client.Config{Host: testServer.URL, Version: testapi.Version()})
+	manager := NewReplicationManager(client)
+	fakePodControl := FakePodControl{}
+	manager.podControl = &fakePodControl
+
+	manager.synchronize()
+
+	// Status.Replicas should go up from 2->4 even though we created 5-4=1 pod
+	rc.Status = api.ReplicationControllerStatus{Replicas: 4}
+	decRc := runtime.EncodeOrDie(testapi.Codec(), &rc)
+	fakeUpdateHandler.ValidateRequest(t, fmt.Sprintf("/api/"+testapi.Version()+"/replicationControllers/%s?namespace=%s", rc.Name, rc.Namespace), "PUT", &decRc)
+	validateSyncReplication(t, &fakePodControl, 1, 0)
+}
+
 type FakeWatcher struct {
 	w *watch.FakeWatcher
 	*client.Fake

pkg/registry/controller/rest.go

@@ -23,7 +23,6 @@ import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api/rest"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api/validation"
-	rc "github.com/GoogleCloudPlatform/kubernetes/pkg/controller"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/fields"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
@@ -78,7 +77,6 @@ func (rs *REST) Get(ctx api.Context, id string) (runtime.Object, error) {
 	if err != nil {
 		return nil, err
 	}
-	rs.fillCurrentState(ctx, controller)
 	return controller, err
 }
 
@@ -94,7 +92,6 @@ func (rs *REST) List(ctx api.Context, label labels.Selector, field fields.Select
 	filtered := []api.ReplicationController{}
 	for _, controller := range controllers.Items {
 		if label.Matches(labels.Set(controller.Labels)) {
-			rs.fillCurrentState(ctx, &controller)
 			filtered = append(filtered, controller)
 		}
 	}
@@ -133,16 +130,3 @@ func (rs *REST) Update(ctx api.Context, obj runtime.Object) (runtime.Object, boo
 func (rs *REST) Watch(ctx api.Context, label labels.Selector, field fields.Selector, resourceVersion string) (watch.Interface, error) {
 	return rs.registry.WatchControllers(ctx, label, field, resourceVersion)
 }
-
-// TODO #2726: The controller should populate the current state, not the apiserver
-func (rs *REST) fillCurrentState(ctx api.Context, controller *api.ReplicationController) error {
-	if rs.podLister == nil {
-		return nil
-	}
-	list, err := rs.podLister.ListPods(ctx, labels.Set(controller.Spec.Selector).AsSelector())
-	if err != nil {
-		return err
-	}
-	controller.Status.Replicas = len(rc.FilterActivePods(list.Items))
-	return nil
-}

pkg/registry/controller/rest_test.go

@@ -20,7 +20,6 @@ import (
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
-	"reflect"
 	"strings"
 	"testing"
 
@@ -354,37 +353,6 @@ func (f *fakePodLister) ListPods(ctx api.Context, s labels.Selector) (*api.PodLi
 	return &f.l, f.e
 }
 
-func TestFillCurrentState(t *testing.T) {
-	fakeLister := fakePodLister{
-		l: api.PodList{
-			Items: []api.Pod{
-				{ObjectMeta: api.ObjectMeta{Name: "foo"}},
-				{ObjectMeta: api.ObjectMeta{Name: "bar"}},
-			},
-		},
-	}
-	mockRegistry := registrytest.ControllerRegistry{}
-	storage := REST{
-		registry:  &mockRegistry,
-		podLister: &fakeLister,
-	}
-	controller := api.ReplicationController{
-		Spec: api.ReplicationControllerSpec{
-			Selector: map[string]string{
-				"foo": "bar",
-			},
-		},
-	}
-	ctx := api.NewContext()
-	storage.fillCurrentState(ctx, &controller)
-	if controller.Status.Replicas != 2 {
-		t.Errorf("expected 2, got: %d", controller.Status.Replicas)
-	}
-	if !reflect.DeepEqual(fakeLister.s, labels.Set(controller.Spec.Selector).AsSelector()) {
-		t.Errorf("unexpected output: %#v %#v", labels.Set(controller.Spec.Selector).AsSelector(), fakeLister.s)
-	}
-}
-
 // TODO: remove, covered by TestCreate
 func TestCreateControllerWithGeneratedName(t *testing.T) {
 	storage := NewREST(&registrytest.ControllerRegistry{}, nil)