* Update pod status only when it changes.

* Refactor syncing logic into a separate struct

pkg/kubelet/status_manager_test.go

@@ -0,0 +1,83 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package kubelet
+
+import (
+	"math/rand"
+	"strconv"
+	"testing"
+
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/client"
+)
+
+const (
+	podFullName string = "podName_namespace"
+)
+
+func newTestStatusManager() *statusManager {
+	return newStatusManager(&client.Fake{})
+}
+
+func generateRandomMessage() string {
+	return strconv.Itoa(rand.Int())
+}
+
+func getRandomPodStatus() api.PodStatus {
+	return api.PodStatus{
+		Message: generateRandomMessage(),
+	}
+}
+
+func verifyActions(t *testing.T, kubeClient client.Interface, expectedActions []string) {
+	actions := kubeClient.(*client.Fake).Actions
+	if len(actions) != len(expectedActions) {
+		t.Errorf("unexpected actions, got: %s expected: %s", actions, expectedActions)
+		return
+	}
+	for i := 0; i < len(actions); i++ {
+		if actions[i].Action != expectedActions[i] {
+			t.Errorf("unexpected actions, got: %s expected: %s", actions, expectedActions)
+		}
+	}
+}
+
+func TestNewStatus(t *testing.T) {
+	syncer := newTestStatusManager()
+	syncer.SetPodStatus(podFullName, getRandomPodStatus())
+	syncer.SyncBatch()
+	verifyActions(t, syncer.kubeClient, []string{"update-status-pod"})
+}
+
+func TestChangedStatus(t *testing.T) {
+	syncer := newTestStatusManager()
+	syncer.SetPodStatus(podFullName, getRandomPodStatus())
+	syncer.SyncBatch()
+	syncer.SetPodStatus(podFullName, getRandomPodStatus())
+	syncer.SyncBatch()
+	verifyActions(t, syncer.kubeClient, []string{"update-status-pod", "update-status-pod"})
+}
+
+func TestUnchangedStatus(t *testing.T) {
+	syncer := newTestStatusManager()
+	podStatus := getRandomPodStatus()
+	syncer.SetPodStatus(podFullName, podStatus)
+	syncer.SyncBatch()
+	syncer.SetPodStatus(podFullName, podStatus)
+	syncer.SyncBatch()
+	verifyActions(t, syncer.kubeClient, []string{"update-status-pod"})
+}