func TestExtractControllerJson(t *testing.T) {
	mockRegistry := MockControllerRegistry{}
	storage := ControllerRegistryStorage{
		registry: &mockRegistry,
	}
	controller := api.ReplicationController{
		JSONBase: api.JSONBase{
			ID: "foo",
		},
	}
	body, err := json.Marshal(controller)
	expectNoError(t, err)
	controllerOut, err := storage.Extract(string(body))
	expectNoError(t, err)
	// Extract adds a Kind
	controller.Kind = "cluster#replicationController"
	if !reflect.DeepEqual(controller, controllerOut) {
		t.Errorf("Expected %#v, found %#v", controller, controllerOut)
	}
}
func (storage *ControllerRegistryStorage) Extract(body string) (interface{}, error) {
	result := api.ReplicationController{}
	err := json.Unmarshal([]byte(body), &result)
	result.Kind = "cluster#replicationController"
	return result, err
}