Add the resource version to api.*List items from etcd

Allows clients to watch more easily (can invoke Get, then
Watch).

pkg/master/pod_cache.go

@@ -77,7 +77,7 @@ func (p *PodCache) UpdateAllContainers() {
 		glog.Errorf("Error synchronizing container list: %v", err)
 		return
 	}
-	for _, pod := range pods {
+	for _, pod := range pods.Items {
 		err := p.updatePodInfo(pod.CurrentState.Host, pod.ID)
 		if err != nil && err != client.ErrPodInfoNotAvailable {
 			glog.Errorf("Error synchronizing container: %v", err)

pkg/master/pod_cache_test.go

@@ -96,7 +96,7 @@ func TestPodUpdateAllContainers(t *testing.T) {
 	}
 
 	pods := []api.Pod{pod}
-	mockRegistry := registrytest.NewPodRegistry(pods)
+	mockRegistry := registrytest.NewPodRegistry(&api.PodList{Items: pods})
 
 	expected := api.PodInfo{"foo": docker.Container{ID: "foo"}}
 	fake := FakePodInfoGetter{

pkg/registry/controller/registry.go

@@ -23,7 +23,7 @@ import (
 
 // Registry is an interface for things that know how to store ReplicationControllers.
 type Registry interface {
-	ListControllers() ([]api.ReplicationController, error)
+	ListControllers() (*api.ReplicationControllerList, error)
 	WatchControllers(resourceVersion uint64) (watch.Interface, error)
 	GetController(controllerID string) (*api.ReplicationController, error)
 	CreateController(controller api.ReplicationController) error

pkg/registry/controller/storage.go

@@ -92,16 +92,18 @@ func (rs *RegistryStorage) Get(id string) (interface{}, error) {
 
 // List obtains a list of ReplicationControllers that match selector.
 func (rs *RegistryStorage) List(selector labels.Selector) (interface{}, error) {
-	result := api.ReplicationControllerList{}
 	controllers, err := rs.registry.ListControllers()
-	if err == nil {
-		for _, controller := range controllers {
-			if selector.Matches(labels.Set(controller.Labels)) {
-				result.Items = append(result.Items, controller)
-			}
+	if err != nil {
+		return nil, err
+	}
+	filtered := []api.ReplicationController{}
+	for _, controller := range controllers.Items {
+		if selector.Matches(labels.Set(controller.Labels)) {
+			filtered = append(filtered, controller)
 		}
 	}
-	return result, err
+	controllers.Items = filtered
+	return controllers, err
 }
 
 // New creates a new ReplicationController for use with Create and Update.
@@ -150,7 +152,7 @@ func (rs *RegistryStorage) waitForController(ctrl api.ReplicationController) (in
 		if err != nil {
 			return ctrl, err
 		}
-		if len(pods) == ctrl.DesiredState.Replicas {
+		if len(pods.Items) == ctrl.DesiredState.Replicas {
 			break
 		}
 		time.Sleep(rs.pollPeriod)

pkg/registry/controller/storage_test.go

@@ -37,18 +37,17 @@ func TestListControllersError(t *testing.T) {
 	storage := RegistryStorage{
 		registry: &mockRegistry,
 	}
-	controllersObj, err := storage.List(nil)
-	controllers := controllersObj.(api.ReplicationControllerList)
+	controllers, err := storage.List(nil)
 	if err != mockRegistry.Err {
 		t.Errorf("Expected %#v, Got %#v", mockRegistry.Err, err)
 	}
-	if len(controllers.Items) != 0 {
-		t.Errorf("Unexpected non-zero ctrl list: %#v", controllers)
+	if controllers != nil {
+		t.Errorf("Unexpected non-nil ctrl list: %#v", controllers)
 	}
 }
 
 func TestListEmptyControllerList(t *testing.T) {
-	mockRegistry := registrytest.ControllerRegistry{}
+	mockRegistry := registrytest.ControllerRegistry{nil, &api.ReplicationControllerList{JSONBase: api.JSONBase{ResourceVersion: 1}}}
 	storage := RegistryStorage{
 		registry: &mockRegistry,
 	}
@@ -57,22 +56,27 @@ func TestListEmptyControllerList(t *testing.T) {
 		t.Errorf("unexpected error: %v", err)
 	}
 
-	if len(controllers.(api.ReplicationControllerList).Items) != 0 {
+	if len(controllers.(*api.ReplicationControllerList).Items) != 0 {
 		t.Errorf("Unexpected non-zero ctrl list: %#v", controllers)
 	}
+	if controllers.(*api.ReplicationControllerList).ResourceVersion != 1 {
+		t.Errorf("Unexpected resource version: %#v", controllers)
+	}
 }
 
 func TestListControllerList(t *testing.T) {
 	mockRegistry := registrytest.ControllerRegistry{
-		Controllers: []api.ReplicationController{
-			{
-				JSONBase: api.JSONBase{
-					ID: "foo",
+		Controllers: &api.ReplicationControllerList{
+			Items: []api.ReplicationController{
+				{
+					JSONBase: api.JSONBase{
+						ID: "foo",
+					},
 				},
-			},
-			{
-				JSONBase: api.JSONBase{
-					ID: "bar",
+				{
+					JSONBase: api.JSONBase{
+						ID: "bar",
+					},
 				},
 			},
 		},
@@ -81,7 +85,7 @@ func TestListControllerList(t *testing.T) {
 		registry: &mockRegistry,
 	}
 	controllersObj, err := storage.List(labels.Everything())
-	controllers := controllersObj.(api.ReplicationControllerList)
+	controllers := controllersObj.(*api.ReplicationControllerList)
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
 	}
@@ -212,10 +216,12 @@ var validPodTemplate = api.PodTemplate{
 func TestCreateController(t *testing.T) {
 	mockRegistry := registrytest.ControllerRegistry{}
 	mockPodRegistry := registrytest.PodRegistry{
-		Pods: []api.Pod{
-			{
-				JSONBase: api.JSONBase{ID: "foo"},
-				Labels:   map[string]string{"a": "b"},
+		Pods: &api.PodList{
+			Items: []api.Pod{
+				{
+					JSONBase: api.JSONBase{ID: "foo"},
+					Labels:   map[string]string{"a": "b"},
+				},
 			},
 		},
 	}

pkg/registry/etcd/etcd.go

@@ -59,22 +59,24 @@ func makePodKey(podID string) string {
 }
 
 // ListPods obtains a list of pods that match selector.
-func (r *Registry) ListPods(selector labels.Selector) ([]api.Pod, error) {
-	allPods := []api.Pod{}
-	filteredPods := []api.Pod{}
-	if err := r.ExtractList("/registry/pods", &allPods); err != nil {
+func (r *Registry) ListPods(selector labels.Selector) (*api.PodList, error) {
+	allPods := api.PodList{}
+	err := r.ExtractList("/registry/pods", &allPods.Items, &allPods.ResourceVersion)
+	if err != nil {
 		return nil, err
 	}
-	for _, pod := range allPods {
+	filtered := []api.Pod{}
+	for _, pod := range allPods.Items {
 		if selector.Matches(labels.Set(pod.Labels)) {
 			// TODO: Currently nothing sets CurrentState.Host. We need a feedback loop that sets
 			// the CurrentState.Host and Status fields. Here we pretend that reality perfectly
 			// matches our desires.
 			pod.CurrentState.Host = pod.DesiredState.Host
-			filteredPods = append(filteredPods, pod)
+			filtered = append(filtered, pod)
 		}
 	}
-	return filteredPods, nil
+	allPods.Items = filtered
+	return &allPods, nil
 }
 
 // WatchPods begins watching for new, changed, or deleted pods.
@@ -225,9 +227,9 @@ func (r *Registry) DeletePod(podID string) error {
 }
 
 // ListControllers obtains a list of ReplicationControllers.
-func (r *Registry) ListControllers() ([]api.ReplicationController, error) {
-	var controllers []api.ReplicationController
-	err := r.ExtractList("/registry/controllers", &controllers)
+func (r *Registry) ListControllers() (*api.ReplicationControllerList, error) {
+	controllers := &api.ReplicationControllerList{}
+	err := r.ExtractList("/registry/controllers", &controllers.Items, &controllers.ResourceVersion)
 	return controllers, err
 }
 
@@ -283,9 +285,9 @@ func makeServiceKey(name string) string {
 }
 
 // ListServices obtains a list of Services.
-func (r *Registry) ListServices() (api.ServiceList, error) {
-	var list api.ServiceList
-	err := r.ExtractList("/registry/services/specs", &list.Items)
+func (r *Registry) ListServices() (*api.ServiceList, error) {
+	list := &api.ServiceList{}
+	err := r.ExtractList("/registry/services/specs", &list.Items, &list.ResourceVersion)
 	return list, err
 }
 

pkg/registry/etcd/etcd_test.go

@@ -412,7 +412,7 @@ func TestEtcdEmptyListPods(t *testing.T) {
 		t.Errorf("unexpected error: %v", err)
 	}
 
-	if len(pods) != 0 {
+	if len(pods.Items) != 0 {
 		t.Errorf("Unexpected pod list: %#v", pods)
 	}
 }
@@ -430,7 +430,7 @@ func TestEtcdListPodsNotFound(t *testing.T) {
 		t.Errorf("unexpected error: %v", err)
 	}
 
-	if len(pods) != 0 {
+	if len(pods.Items) != 0 {
 		t.Errorf("Unexpected pod list: %#v", pods)
 	}
 }
@@ -465,11 +465,11 @@ func TestEtcdListPods(t *testing.T) {
 		t.Errorf("unexpected error: %v", err)
 	}
 
-	if len(pods) != 2 || pods[0].ID != "foo" || pods[1].ID != "bar" {
+	if len(pods.Items) != 2 || pods.Items[0].ID != "foo" || pods.Items[1].ID != "bar" {
 		t.Errorf("Unexpected pod list: %#v", pods)
 	}
-	if pods[0].CurrentState.Host != "machine" ||
-		pods[1].CurrentState.Host != "machine" {
+	if pods.Items[0].CurrentState.Host != "machine" ||
+		pods.Items[1].CurrentState.Host != "machine" {
 		t.Errorf("Failed to populate host name.")
 	}
 }
@@ -487,7 +487,7 @@ func TestEtcdListControllersNotFound(t *testing.T) {
 		t.Errorf("unexpected error: %v", err)
 	}
 
-	if len(controllers) != 0 {
+	if len(controllers.Items) != 0 {
 		t.Errorf("Unexpected controller list: %#v", controllers)
 	}
 }
@@ -534,7 +534,7 @@ func TestEtcdListControllers(t *testing.T) {
 		t.Errorf("unexpected error: %v", err)
 	}
 
-	if len(controllers) != 2 || controllers[0].ID != "foo" || controllers[1].ID != "bar" {
+	if len(controllers.Items) != 2 || controllers.Items[0].ID != "foo" || controllers.Items[1].ID != "bar" {
 		t.Errorf("Unexpected controller list: %#v", controllers)
 	}
 }

pkg/registry/pod/registry.go

@@ -25,7 +25,7 @@ import (
 // Registry is an interface implemented by things that know how to store Pod objects.
 type Registry interface {
 	// ListPods obtains a list of pods that match selector.
-	ListPods(selector labels.Selector) ([]api.Pod, error)
+	ListPods(selector labels.Selector) (*api.PodList, error)
 	// Watch for new/changed/deleted pods
 	WatchPods(resourceVersion uint64, filter func(*api.Pod) bool) (watch.Interface, error)
 	// Get a specific pod

pkg/registry/pod/storage.go

@@ -105,15 +105,13 @@ func (rs *RegistryStorage) Get(id string) (interface{}, error) {
 }
 
 func (rs *RegistryStorage) List(selector labels.Selector) (interface{}, error) {
-	var result api.PodList
 	pods, err := rs.registry.ListPods(selector)
 	if err == nil {
-		result.Items = pods
-		for i := range result.Items {
-			rs.fillPodInfo(&result.Items[i])
+		for i := range pods.Items {
+			rs.fillPodInfo(&pods.Items[i])
 		}
 	}
-	return result, err
+	return pods, err
 }
 
 // Watch begins watching for new, changed, or deleted pods.

pkg/registry/pod/storage_test.go

@@ -108,13 +108,13 @@ func TestListPodsError(t *testing.T) {
 	if err != podRegistry.Err {
 		t.Errorf("Expected %#v, Got %#v", podRegistry.Err, err)
 	}
-	if len(pods.(api.PodList).Items) != 0 {
-		t.Errorf("Unexpected non-zero pod list: %#v", pods)
+	if pods.(*api.PodList) != nil {
+		t.Errorf("Unexpected non-nil pod list: %#v", pods)
 	}
 }
 
 func TestListEmptyPodList(t *testing.T) {
-	podRegistry := registrytest.NewPodRegistry(nil)
+	podRegistry := registrytest.NewPodRegistry(&api.PodList{JSONBase: api.JSONBase{ResourceVersion: 1}})
 	storage := RegistryStorage{
 		registry: podRegistry,
 	}
@@ -123,22 +123,27 @@ func TestListEmptyPodList(t *testing.T) {
 		t.Errorf("unexpected error: %v", err)
 	}
 
-	if len(pods.(api.PodList).Items) != 0 {
+	if len(pods.(*api.PodList).Items) != 0 {
 		t.Errorf("Unexpected non-zero pod list: %#v", pods)
 	}
+	if pods.(*api.PodList).ResourceVersion != 1 {
+		t.Errorf("Unexpected resource version: %#v", pods)
+	}
 }
 
 func TestListPodList(t *testing.T) {
 	podRegistry := registrytest.NewPodRegistry(nil)
-	podRegistry.Pods = []api.Pod{
-		{
-			JSONBase: api.JSONBase{
-				ID: "foo",
+	podRegistry.Pods = &api.PodList{
+		Items: []api.Pod{
+			{
+				JSONBase: api.JSONBase{
+					ID: "foo",
+				},
 			},
-		},
-		{
-			JSONBase: api.JSONBase{
-				ID: "bar",
+			{
+				JSONBase: api.JSONBase{
+					ID: "bar",
+				},
 			},
 		},
 	}
@@ -146,7 +151,7 @@ func TestListPodList(t *testing.T) {
 		registry: podRegistry,
 	}
 	podsObj, err := storage.List(labels.Everything())
-	pods := podsObj.(api.PodList)
+	pods := podsObj.(*api.PodList)
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
 	}

pkg/registry/registrytest/controller.go

@@ -24,10 +24,10 @@ import (
 // TODO: Why do we have this AND MemoryRegistry?
 type ControllerRegistry struct {
 	Err         error
-	Controllers []api.ReplicationController
+	Controllers *api.ReplicationControllerList
 }
 
-func (r *ControllerRegistry) ListControllers() ([]api.ReplicationController, error) {
+func (r *ControllerRegistry) ListControllers() (*api.ReplicationControllerList, error) {
 	return r.Controllers, r.Err
 }
 

pkg/registry/registrytest/pod.go

@@ -27,32 +27,34 @@ import (
 type PodRegistry struct {
 	Err  error
 	Pod  *api.Pod
-	Pods []api.Pod
+	Pods *api.PodList
 	sync.Mutex
 
 	mux *watch.Mux
 }
 
-func NewPodRegistry(pods []api.Pod) *PodRegistry {
+func NewPodRegistry(pods *api.PodList) *PodRegistry {
 	return &PodRegistry{
 		Pods: pods,
 		mux:  watch.NewMux(0),
 	}
 }
 
-func (r *PodRegistry) ListPods(selector labels.Selector) ([]api.Pod, error) {
+func (r *PodRegistry) ListPods(selector labels.Selector) (*api.PodList, error) {
 	r.Lock()
 	defer r.Unlock()
 	if r.Err != nil {
-		return r.Pods, r.Err
+		return nil, r.Err
 	}
 	var filtered []api.Pod
-	for _, pod := range r.Pods {
+	for _, pod := range r.Pods.Items {
 		if selector.Matches(labels.Set(pod.Labels)) {
 			filtered = append(filtered, pod)
 		}
 	}
-	return filtered, nil
+	pods := *r.Pods
+	pods.Items = filtered
+	return &pods, nil
 }
 
 func (r *PodRegistry) WatchPods(resourceVersion uint64, filter func(*api.Pod) bool) (watch.Interface, error) {

pkg/registry/registrytest/service.go

@@ -37,8 +37,8 @@ type ServiceRegistry struct {
 	UpdatedID string
 }
 
-func (r *ServiceRegistry) ListServices() (api.ServiceList, error) {
-	return r.List, r.Err
+func (r *ServiceRegistry) ListServices() (*api.ServiceList, error) {
+	return &r.List, r.Err
 }
 
 func (r *ServiceRegistry) CreateService(svc api.Service) error {

pkg/registry/service/registry.go

@@ -25,7 +25,7 @@ import (
 
 // Registry is an interface for things that know how to store services.
 type Registry interface {
-	ListServices() (api.ServiceList, error)
+	ListServices() (*api.ServiceList, error)
 	CreateService(svc api.Service) error
 	GetService(name string) (*api.Service, error)
 	DeleteService(name string) error

pkg/registry/service/storage_test.go

@@ -317,8 +317,9 @@ func TestServiceRegistryList(t *testing.T) {
 		JSONBase: api.JSONBase{ID: "foo2"},
 		Selector: map[string]string{"bar2": "baz2"},
 	})
+	registry.List.ResourceVersion = 1
 	s, _ := storage.List(labels.Everything())
-	sl := s.(api.ServiceList)
+	sl := s.(*api.ServiceList)
 	if len(fakeCloud.Calls) != 0 {
 		t.Errorf("Unexpected call(s): %#v", fakeCloud.Calls)
 	}
@@ -331,4 +332,7 @@ func TestServiceRegistryList(t *testing.T) {
 	if e, a := "foo2", sl.Items[1].ID; e != a {
 		t.Errorf("Expected %v, but got %v", e, a)
 	}
+	if sl.ResourceVersion != 1 {
+		t.Errorf("Unexpected resource version: %#v", sl)
+	}
 }

pkg/tools/etcd_tools.go

@@ -117,22 +117,29 @@ func etcdErrorIndex(err error) (uint64, bool) {
 	return 0, false
 }
 
-func (h *EtcdHelper) listEtcdNode(key string) ([]*etcd.Node, error) {
+func (h *EtcdHelper) listEtcdNode(key string) ([]*etcd.Node, uint64, error) {
 	result, err := h.Client.Get(key, false, true)
 	if err != nil {
+		index, ok := etcdErrorIndex(err)
+		if !ok {
+			index = 0
+		}
 		nodes := make([]*etcd.Node, 0)
 		if IsEtcdNotFound(err) {
-			return nodes, nil
+			return nodes, index, nil
 		} else {
-			return nodes, err
+			return nodes, index, err
 		}
 	}
-	return result.Node.Nodes, nil
+	return result.Node.Nodes, result.EtcdIndex, nil
 }
 
-// Extract a go object per etcd node into a slice.
-func (h *EtcdHelper) ExtractList(key string, slicePtr interface{}) error {
-	nodes, err := h.listEtcdNode(key)
+// Extract a go object per etcd node into a slice with the resource version.
+func (h *EtcdHelper) ExtractList(key string, slicePtr interface{}, resourceVersion *uint64) error {
+	nodes, index, err := h.listEtcdNode(key)
+	if resourceVersion != nil {
+		*resourceVersion = index
+	}
 	if err != nil {
 		return err
 	}

pkg/tools/etcd_tools_test.go

@@ -66,6 +66,7 @@ func TestExtractList(t *testing.T) {
 	fakeClient := NewFakeEtcdClient(t)
 	fakeClient.Data["/some/key"] = EtcdResponseWithError{
 		R: &etcd.Response{
+			EtcdIndex: 10,
 			Node: &etcd.Node{
 				Nodes: []*etcd.Node{
 					{
@@ -92,10 +93,14 @@ func TestExtractList(t *testing.T) {
 
 	var got []api.Pod
 	helper := EtcdHelper{fakeClient, codec, versioner}
-	err := helper.ExtractList("/some/key", &got)
+	resourceVersion := uint64(0)
+	err := helper.ExtractList("/some/key", &got, &resourceVersion)
 	if err != nil {
 		t.Errorf("Unexpected error %#v", err)
 	}
+	if resourceVersion != 10 {
+		t.Errorf("Unexpected resource version %d", resourceVersion)
+	}
 
 	for i := 0; i < len(expect); i++ {
 		if !reflect.DeepEqual(got[i], expect[i]) {