RcManager uses informers

pkg/client/cache/listers.go

@@ -123,6 +123,59 @@ func (s *StoreToNodeLister) GetNodeInfo(id string) (*api.Node, error) {
 	return minion.(*api.Node), nil
 }
 
+// StoreToControllerLister gives a store List and Exists methods. The store must contain only ReplicationControllers.
+type StoreToControllerLister struct {
+	Store
+}
+
+// Exists checks if the given rc exists in the store.
+func (s *StoreToControllerLister) Exists(controller *api.ReplicationController) (bool, error) {
+	_, exists, err := s.Store.Get(controller)
+	if err != nil {
+		return false, err
+	}
+	return exists, nil
+}
+
+// StoreToControllerLister lists all controllers in the store.
+// TODO: converge on the interface in pkg/client
+func (s *StoreToControllerLister) List() (controllers []api.ReplicationController, err error) {
+	for _, c := range s.Store.List() {
+		controllers = append(controllers, *(c.(*api.ReplicationController)))
+	}
+	return controllers, nil
+}
+
+// GetPodControllers returns a list of controllers managing a pod. Returns an error only if no matching controllers are found.
+func (s *StoreToControllerLister) GetPodControllers(pod *api.Pod) (controllers []api.ReplicationController, err error) {
+	var selector labels.Selector
+	var rc api.ReplicationController
+
+	if len(pod.Labels) == 0 {
+		err = fmt.Errorf("No controllers found for pod %v because it has no labels", pod.Name)
+		return
+	}
+
+	for _, m := range s.Store.List() {
+		rc = *m.(*api.ReplicationController)
+		if rc.Namespace != pod.Namespace {
+			continue
+		}
+		labelSet := labels.Set(rc.Spec.Selector)
+		selector = labels.Set(rc.Spec.Selector).AsSelector()
+
+		// If an rc with a nil or empty selector creeps in, it should match nothing, not everything.
+		if labelSet.AsSelector().Empty() || !selector.Matches(labels.Set(pod.Labels)) {
+			continue
+		}
+		controllers = append(controllers, rc)
+	}
+	if len(controllers) == 0 {
+		err = fmt.Errorf("Could not find controllers for pod %s in namespace %s with labels: %v", pod.Name, pod.Namespace, pod.Labels)
+	}
+	return
+}
+
 // StoreToServiceLister makes a Store that has the List method of the client.ServiceInterface
 // The Store must contain (only) Services.
 type StoreToServiceLister struct {

pkg/client/cache/listers_test.go

@@ -45,6 +45,116 @@ func TestStoreToMinionLister(t *testing.T) {
 	}
 }
 
+func TestStoreToControllerLister(t *testing.T) {
+	store := NewStore(MetaNamespaceKeyFunc)
+	lister := StoreToControllerLister{store}
+	testCases := []struct {
+		inRCs      []*api.ReplicationController
+		list       func() ([]api.ReplicationController, error)
+		outRCNames util.StringSet
+		expectErr  bool
+	}{
+		// Basic listing with all labels and no selectors
+		{
+			inRCs: []*api.ReplicationController{
+				{ObjectMeta: api.ObjectMeta{Name: "basic"}},
+			},
+			list: func() ([]api.ReplicationController, error) {
+				return lister.List()
+			},
+			outRCNames: util.NewStringSet("basic"),
+		},
+		// No pod lables
+		{
+			inRCs: []*api.ReplicationController{
+				{
+					ObjectMeta: api.ObjectMeta{Name: "basic", Namespace: "ns"},
+					Spec: api.ReplicationControllerSpec{
+						Selector: map[string]string{"foo": "baz"},
+					},
+				},
+			},
+			list: func() ([]api.ReplicationController, error) {
+				pod := &api.Pod{
+					ObjectMeta: api.ObjectMeta{Name: "pod1", Namespace: "ns"},
+				}
+				return lister.GetPodControllers(pod)
+			},
+			outRCNames: util.NewStringSet(),
+			expectErr:  true,
+		},
+		// No RC selectors
+		{
+			inRCs: []*api.ReplicationController{
+				{
+					ObjectMeta: api.ObjectMeta{Name: "basic", Namespace: "ns"},
+				},
+			},
+			list: func() ([]api.ReplicationController, error) {
+				pod := &api.Pod{
+					ObjectMeta: api.ObjectMeta{
+						Name:      "pod1",
+						Namespace: "ns",
+						Labels:    map[string]string{"foo": "bar"},
+					},
+				}
+				return lister.GetPodControllers(pod)
+			},
+			outRCNames: util.NewStringSet(),
+			expectErr:  true,
+		},
+		// Matching labels to selectors and namespace
+		{
+			inRCs: []*api.ReplicationController{
+				{
+					ObjectMeta: api.ObjectMeta{Name: "foo"},
+					Spec: api.ReplicationControllerSpec{
+						Selector: map[string]string{"foo": "bar"},
+					},
+				},
+				{
+					ObjectMeta: api.ObjectMeta{Name: "bar", Namespace: "ns"},
+					Spec: api.ReplicationControllerSpec{
+						Selector: map[string]string{"foo": "bar"},
+					},
+				},
+			},
+			list: func() ([]api.ReplicationController, error) {
+				pod := &api.Pod{
+					ObjectMeta: api.ObjectMeta{
+						Name:      "pod1",
+						Labels:    map[string]string{"foo": "bar"},
+						Namespace: "ns",
+					},
+				}
+				return lister.GetPodControllers(pod)
+			},
+			outRCNames: util.NewStringSet("bar"),
+		},
+	}
+	for _, c := range testCases {
+		for _, r := range c.inRCs {
+			store.Add(r)
+		}
+
+		gotControllers, err := c.list()
+		if err != nil && c.expectErr {
+			continue
+		} else if c.expectErr {
+			t.Fatalf("Expected error, got none")
+		} else if err != nil {
+			t.Fatalf("Unexpected error %#v", err)
+		}
+		gotNames := make([]string, len(gotControllers))
+		for ix := range gotControllers {
+			gotNames[ix] = gotControllers[ix].Name
+		}
+		if !c.outRCNames.HasAll(gotNames...) || len(gotNames) != len(c.outRCNames) {
+			t.Errorf("Unexpected got controllers %+v expected %+v", gotNames, c.outRCNames)
+		}
+	}
+}
+
 func TestStoreToPodLister(t *testing.T) {
 	store := NewStore(MetaNamespaceKeyFunc)
 	ids := []string{"foo", "bar", "baz"}