Merge pull request #5748 from yujuhong/refactor

Kubelet: add podManager for managing internal pod storage

pkg/kubelet/kubelet.go

@@ -229,6 +229,8 @@ func NewMainKubelet(
 		imageManager:                   imageManager,
 	}
 
+	klet.podManager = newBasicPodManager(klet.kubeClient)
+
 	dockerCache, err := dockertools.NewDockerCache(dockerClient)
 	if err != nil {
 		return nil, err
@@ -253,8 +255,6 @@ func NewMainKubelet(
 
 	klet.podStatuses = make(map[string]api.PodStatus)
 
-	klet.mirrorManager = newBasicMirrorManager(klet.kubeClient)
-
 	return klet, nil
 }
 
@@ -285,20 +285,10 @@ type Kubelet struct {
 	podStatusUpdateFrequency time.Duration
 	sourcesReady             SourcesReadyFn
 
-	// Protects the pods array
-	// We make complete array copies out of this while locked, which is OK because once added to this array,
-	// pods are immutable
-	podLock sync.RWMutex
-	pods    []api.Pod
-	// Record the set of mirror pods (see mirror_manager.go for more details);
-	// similar to pods, this is not immutable and is protected by the same podLock.
-	// Note that Kubelet.pods do not contain mirror pods as they are filtered
-	// out beforehand.
-	mirrorPods mirrorPods
-
+	podManager podManager
 	// A pod status cache stores statuses for pods (both rejected and synced).
 	// Note that currently no thread attempts to acquire podStatusesLock while
-	// holding podLock, and vice versa. If you intend to change this usage
+	// accessing podManager, and vice versa. If you intend to change this usage
 	// pattern, please explicitly impose an acquiring order to avoid deadlocks
 	// and document such an order in the comment.
 	podStatusesLock sync.RWMutex
@@ -353,9 +343,6 @@ type Kubelet struct {
 	// the EventRecorder to use
 	recorder record.EventRecorder
 
-	// A mirror pod manager which provides helper functions.
-	mirrorManager mirrorManager
-
 	// Policy for handling garbage collection of dead containers.
 	containerGC containerGC
 
@@ -1445,7 +1432,7 @@ func (kl *Kubelet) syncPod(pod *api.Pod, hasMirrorPod bool, containersInPod dock
 
 	if !hasMirrorPod && isStaticPod(pod) {
 		glog.V(4).Infof("Creating a mirror pod %q", podFullName)
-		if err := kl.mirrorManager.CreateMirrorPod(*pod, kl.hostname); err != nil {
+		if err := kl.podManager.CreateMirrorPod(*pod, kl.hostname); err != nil {
 			glog.Errorf("Failed creating a mirror pod %q: %#v", podFullName, err)
 		}
 	}
@@ -1572,7 +1559,7 @@ func (kl *Kubelet) SyncPods(allPods []api.Pod, podSyncTypes map[types.UID]metric
 		}
 
 		// Run the sync in an async manifest worker.
-		kl.podWorkers.UpdatePod(pod, kl.mirrorPods.HasMirrorPod(uid), func() {
+		kl.podWorkers.UpdatePod(pod, mirrorPods.HasMirrorPod(uid), func() {
 			metrics.SyncPodLatency.WithLabelValues(podSyncTypes[pod.UID].String()).Observe(metrics.SinceInMicroseconds(start))
 		})
 
@@ -1641,33 +1628,11 @@ func (kl *Kubelet) SyncPods(allPods []api.Pod, podSyncTypes map[types.UID]metric
 	}
 
 	// Remove any orphaned mirror pods.
-	deleteOrphanedMirrorPods(mirrorPods, kl.mirrorManager)
+	kl.podManager.DeleteOrphanedMirrorPods(&mirrorPods)
 
 	return err
 }
 
-func updatePods(changed []api.Pod, current []api.Pod) []api.Pod {
-	updated := []api.Pod{}
-	m := map[types.UID]*api.Pod{}
-	for i := range changed {
-		pod := &changed[i]
-		m[pod.UID] = pod
-	}
-
-	for i := range current {
-		pod := &current[i]
-		if m[pod.UID] != nil {
-			updated = append(updated, *m[pod.UID])
-			glog.V(4).Infof("pod with UID: %q has a new spec %+v", pod.UID, *m[pod.UID])
-		} else {
-			updated = append(updated, *pod)
-			glog.V(4).Infof("pod with UID: %q stay with the same spec %+v", pod.UID, *pod)
-		}
-	}
-
-	return updated
-}
-
 type podsByCreationTime []api.Pod
 
 func (s podsByCreationTime) Len() int {
@@ -1771,7 +1736,7 @@ func (kl *Kubelet) syncLoop(updates <-chan PodUpdate, handler SyncHandler) {
 		podSyncTypes := make(map[types.UID]metrics.SyncPodType)
 		select {
 		case u := <-updates:
-			kl.updatePods(u, podSyncTypes)
+			kl.podManager.UpdatePods(u, podSyncTypes)
 			unsyncedPod = true
 		case <-time.After(kl.resyncInterval):
 			glog.V(4).Infof("Periodic sync")
@@ -1782,7 +1747,7 @@ func (kl *Kubelet) syncLoop(updates <-chan PodUpdate, handler SyncHandler) {
 		for unsyncedPod {
 			select {
 			case u := <-updates:
-				kl.updatePods(u, podSyncTypes)
+				kl.podManager.UpdatePods(u, podSyncTypes)
 			case <-time.After(5 * time.Millisecond):
 				// Break the for loop.
 				unsyncedPod = false
@@ -1830,52 +1795,6 @@ func (kl *Kubelet) syncStatus(deadline time.Duration) {
 	t.Stop()
 }
 
-// Update the Kubelet's internal pods with those provided by the update.
-// Records new and updated pods in newPods and updatedPods.
-func (kl *Kubelet) updatePods(u PodUpdate, podSyncTypes map[types.UID]metrics.SyncPodType) {
-	kl.podLock.Lock()
-	defer kl.podLock.Unlock()
-	switch u.Op {
-	case SET:
-		glog.V(3).Infof("SET: Containers changed")
-		newPods, newMirrorPods := filterAndCategorizePods(u.Pods)
-
-		// Store the new pods. Don't worry about filtering host ports since those
-		// pods will never be looked up.
-		existingPods := make(map[types.UID]struct{})
-		for i := range kl.pods {
-			existingPods[kl.pods[i].UID] = struct{}{}
-		}
-		for _, pod := range newPods {
-			if _, ok := existingPods[pod.UID]; !ok {
-				podSyncTypes[pod.UID] = metrics.SyncPodCreate
-			}
-		}
-		// Actually update the pods.
-		kl.pods = newPods
-		kl.mirrorPods = newMirrorPods
-	case UPDATE:
-		glog.V(3).Infof("Update: Containers changed")
-
-		// Store the updated pods. Don't worry about filtering host ports since those
-		// pods will never be looked up.
-		for i := range u.Pods {
-			podSyncTypes[u.Pods[i].UID] = metrics.SyncPodUpdate
-		}
-		allPods := updatePods(u.Pods, kl.pods)
-		kl.pods, kl.mirrorPods = filterAndCategorizePods(allPods)
-	default:
-		panic("syncLoop does not support incremental changes")
-	}
-
-	// Mark all remaining pods as sync.
-	for i := range kl.pods {
-		if _, ok := podSyncTypes[kl.pods[i].UID]; !ok {
-			podSyncTypes[u.Pods[i].UID] = metrics.SyncPodSync
-		}
-	}
-}
-
 // Returns Docker version for this Kubelet.
 func (kl *Kubelet) GetDockerVersion() ([]uint, error) {
 	if kl.dockerClient == nil {
@@ -1937,31 +1856,17 @@ func (kl *Kubelet) GetHostname() string {
 // GetPods returns all pods bound to the kubelet and their spec, and the mirror
 // pod map.
 func (kl *Kubelet) GetPods() ([]api.Pod, mirrorPods) {
-	kl.podLock.RLock()
-	defer kl.podLock.RUnlock()
-	return append([]api.Pod{}, kl.pods...), kl.mirrorPods
+	return kl.podManager.GetPods()
 }
 
 func (kl *Kubelet) GetPodByFullName(podFullName string) (*api.Pod, bool) {
-	name, namespace, err := ParsePodFullName(podFullName)
-	if err != nil {
-		return nil, false
-	}
-	return kl.GetPodByName(namespace, name)
+	return kl.podManager.GetPodByFullName(podFullName)
 }
 
 // GetPodByName provides the first pod that matches namespace and name, as well
 // as whether the pod was found.
 func (kl *Kubelet) GetPodByName(namespace, name string) (*api.Pod, bool) {
-	kl.podLock.RLock()
-	defer kl.podLock.RUnlock()
-	for i := range kl.pods {
-		pod := kl.pods[i]
-		if pod.Namespace == namespace && pod.Name == name {
-			return &pod, true
-		}
-	}
-	return nil, false
+	return kl.podManager.GetPodByName(namespace, name)
 }
 
 // updateNodeStatus updates node status to master with retries.
@@ -2108,7 +2013,7 @@ func getPodReadyCondition(spec *api.PodSpec, info api.PodInfo) []api.PodConditio
 
 // GetPodStatus returns information from Docker about the containers in a pod
 func (kl *Kubelet) GetPodStatus(podFullName string, uid types.UID) (api.PodStatus, error) {
-	uid = kl.translatePodUID(uid)
+	uid = kl.podManager.TranslatePodUID(uid)
 
 	// Check to see if we have a cached version of the status.
 	cachedPodStatus, found := kl.getPodStatusFromCache(podFullName)
@@ -2172,7 +2077,7 @@ func (kl *Kubelet) ServeLogs(w http.ResponseWriter, req *http.Request) {
 
 // Run a command in a container, returns the combined stdout, stderr as an array of bytes
 func (kl *Kubelet) RunInContainer(podFullName string, uid types.UID, container string, cmd []string) ([]byte, error) {
-	uid = kl.translatePodUID(uid)
+	uid = kl.podManager.TranslatePodUID(uid)
 
 	if kl.runner == nil {
 		return nil, fmt.Errorf("no runner specified.")
@@ -2191,7 +2096,7 @@ func (kl *Kubelet) RunInContainer(podFullName string, uid types.UID, container s
 // ExecInContainer executes a command in a container, connecting the supplied
 // stdin/stdout/stderr to the command's IO streams.
 func (kl *Kubelet) ExecInContainer(podFullName string, uid types.UID, container string, cmd []string, stdin io.Reader, stdout, stderr io.WriteCloser, tty bool) error {
-	uid = kl.translatePodUID(uid)
+	uid = kl.podManager.TranslatePodUID(uid)
 
 	if kl.runner == nil {
 		return fmt.Errorf("no runner specified.")
@@ -2210,7 +2115,7 @@ func (kl *Kubelet) ExecInContainer(podFullName string, uid types.UID, container
 // PortForward connects to the pod's port and copies data between the port
 // and the stream.
 func (kl *Kubelet) PortForward(podFullName string, uid types.UID, port uint16, stream io.ReadWriteCloser) error {
-	uid = kl.translatePodUID(uid)
+	uid = kl.podManager.TranslatePodUID(uid)
 
 	if kl.runner == nil {
 		return fmt.Errorf("no runner specified.")
@@ -2244,29 +2149,10 @@ func (kl *Kubelet) StreamingConnectionIdleTimeout() time.Duration {
 	return kl.streamingConnectionIdleTimeout
 }
 
-// If the UID belongs to a mirror pod, maps it to the UID of its static pod.
-// Otherwise, return the original UID. All public-facing functions should
-// perform this translation for UIDs because user may provide a mirror pod UID,
-// which is not recognized by internal Kubelet functions.
-func (kl *Kubelet) translatePodUID(uid types.UID) types.UID {
-	if uid == "" {
-		return uid
-	}
-
-	kl.podLock.RLock()
-	defer kl.podLock.RUnlock()
-	staticUID, ok := kl.mirrorPods.GetStaticUID(uid)
-	if ok {
-		return staticUID
-	} else {
-		return uid
-	}
-}
-
 // GetContainerInfo returns stats (from Cadvisor) for a container.
 func (kl *Kubelet) GetContainerInfo(podFullName string, uid types.UID, containerName string, req *cadvisorApi.ContainerInfoRequest) (*cadvisorApi.ContainerInfo, error) {
 
-	uid = kl.translatePodUID(uid)
+	uid = kl.podManager.TranslatePodUID(uid)
 
 	dockerContainers, err := dockertools.GetKubeletDockerContainers(kl.dockerClient, false)
 	if err != nil {

pkg/kubelet/kubelet_test.go

@@ -105,9 +105,9 @@ func newTestKubelet(t *testing.T) *TestKubelet {
 	}
 	mockCadvisor := &cadvisor.Mock{}
 	kubelet.cadvisor = mockCadvisor
-	mirrorManager := newFakeMirrorMananger()
-	kubelet.mirrorManager = mirrorManager
-	return &TestKubelet{kubelet, fakeDocker, mockCadvisor, fakeKubeClient, waitGroup, mirrorManager}
+	podManager, fakeMirrorManager := newFakePodManager()
+	kubelet.podManager = podManager
+	return &TestKubelet{kubelet, fakeDocker, mockCadvisor, fakeKubeClient, waitGroup, fakeMirrorManager}
 }
 
 func verifyCalls(t *testing.T, fakeDocker *dockertools.FakeDockerClient, calls []string) {
@@ -434,7 +434,7 @@ func TestSyncPodsDoesNothing(t *testing.T) {
 			ID:    "9876",
 		},
 	}
-	kubelet.pods = []api.Pod{
+	pods := []api.Pod{
 		{
 			ObjectMeta: api.ObjectMeta{
 				UID:       "12345678",
@@ -448,8 +448,9 @@ func TestSyncPodsDoesNothing(t *testing.T) {
 			},
 		},
 	}
+	kubelet.podManager.SetPods(pods)
 	waitGroup.Add(1)
-	err := kubelet.SyncPods(kubelet.pods, emptyPodUIDs, *newMirrorPods(), time.Now())
+	err := kubelet.SyncPods(pods, emptyPodUIDs, *newMirrorPods(), time.Now())
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
 	}
@@ -468,7 +469,7 @@ func TestSyncPodsWithTerminationLog(t *testing.T) {
 		TerminationMessagePath: "/dev/somepath",
 	}
 	fakeDocker.ContainerList = []docker.APIContainers{}
-	kubelet.pods = []api.Pod{
+	pods := []api.Pod{
 		{
 			ObjectMeta: api.ObjectMeta{
 				UID:       "12345678",
@@ -482,8 +483,9 @@ func TestSyncPodsWithTerminationLog(t *testing.T) {
 			},
 		},
 	}
+	kubelet.podManager.SetPods(pods)
 	waitGroup.Add(1)
-	err := kubelet.SyncPods(kubelet.pods, emptyPodUIDs, *newMirrorPods(), time.Now())
+	err := kubelet.SyncPods(pods, emptyPodUIDs, *newMirrorPods(), time.Now())
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
 	}
@@ -518,7 +520,7 @@ func TestSyncPodsCreatesNetAndContainer(t *testing.T) {
 	waitGroup := testKubelet.waitGroup
 	kubelet.podInfraContainerImage = "custom_image_name"
 	fakeDocker.ContainerList = []docker.APIContainers{}
-	kubelet.pods = []api.Pod{
+	pods := []api.Pod{
 		{
 			ObjectMeta: api.ObjectMeta{
 				UID:       "12345678",
@@ -532,8 +534,9 @@ func TestSyncPodsCreatesNetAndContainer(t *testing.T) {
 			},
 		},
 	}
+	kubelet.podManager.SetPods(pods)
 	waitGroup.Add(1)
-	err := kubelet.SyncPods(kubelet.pods, emptyPodUIDs, *newMirrorPods(), time.Now())
+	err := kubelet.SyncPods(pods, emptyPodUIDs, *newMirrorPods(), time.Now())
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
 	}
@@ -572,7 +575,7 @@ func TestSyncPodsCreatesNetAndContainerPullsImage(t *testing.T) {
 	puller.HasImages = []string{}
 	kubelet.podInfraContainerImage = "custom_image_name"
 	fakeDocker.ContainerList = []docker.APIContainers{}
-	kubelet.pods = []api.Pod{
+	pods := []api.Pod{
 		{
 			ObjectMeta: api.ObjectMeta{
 				UID:       "12345678",
@@ -587,7 +590,8 @@ func TestSyncPodsCreatesNetAndContainerPullsImage(t *testing.T) {
 		},
 	}
 	waitGroup.Add(1)
-	err := kubelet.SyncPods(kubelet.pods, emptyPodUIDs, *newMirrorPods(), time.Now())
+	kubelet.podManager.SetPods(pods)
+	err := kubelet.SyncPods(pods, emptyPodUIDs, *newMirrorPods(), time.Now())
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
 	}
@@ -623,7 +627,7 @@ func TestSyncPodsWithPodInfraCreatesContainer(t *testing.T) {
 			ID:    "9876",
 		},
 	}
-	kubelet.pods = []api.Pod{
+	pods := []api.Pod{
 		{
 			ObjectMeta: api.ObjectMeta{
 				UID:       "12345678",
@@ -638,7 +642,8 @@ func TestSyncPodsWithPodInfraCreatesContainer(t *testing.T) {
 		},
 	}
 	waitGroup.Add(1)
-	err := kubelet.SyncPods(kubelet.pods, emptyPodUIDs, *newMirrorPods(), time.Now())
+	kubelet.podManager.SetPods(pods)
+	err := kubelet.SyncPods(pods, emptyPodUIDs, *newMirrorPods(), time.Now())
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
 	}
@@ -670,7 +675,7 @@ func TestSyncPodsWithPodInfraCreatesContainerCallsHandler(t *testing.T) {
 			ID:    "9876",
 		},
 	}
-	kubelet.pods = []api.Pod{
+	pods := []api.Pod{
 		{
 			ObjectMeta: api.ObjectMeta{
 				UID:       "12345678",
@@ -696,7 +701,8 @@ func TestSyncPodsWithPodInfraCreatesContainerCallsHandler(t *testing.T) {
 		},
 	}
 	waitGroup.Add(1)
-	err := kubelet.SyncPods(kubelet.pods, emptyPodUIDs, *newMirrorPods(), time.Now())
+	kubelet.podManager.SetPods(pods)
+	err := kubelet.SyncPods(pods, emptyPodUIDs, *newMirrorPods(), time.Now())
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
 	}
@@ -739,7 +745,7 @@ func TestSyncPodsDeletesWithNoPodInfraContainer(t *testing.T) {
 			ID:    "8765",
 		},
 	}
-	kubelet.pods = []api.Pod{
+	pods := []api.Pod{
 		{
 			ObjectMeta: api.ObjectMeta{
 				UID:       "12345678",
@@ -766,7 +772,8 @@ func TestSyncPodsDeletesWithNoPodInfraContainer(t *testing.T) {
 		},
 	}
 	waitGroup.Add(2)
-	err := kubelet.SyncPods(kubelet.pods, emptyPodUIDs, *newMirrorPods(), time.Now())
+	kubelet.podManager.SetPods(pods)
+	err := kubelet.SyncPods(pods, emptyPodUIDs, *newMirrorPods(), time.Now())
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
 	}
@@ -907,7 +914,8 @@ func TestSyncPodDeletesDuplicate(t *testing.T) {
 			},
 		},
 	}
-	kubelet.pods = append(kubelet.pods, bound)
+	pods := []api.Pod{bound}
+	kubelet.podManager.SetPods(pods)
 	err := kubelet.syncPod(&bound, false, dockerContainers)
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
@@ -948,7 +956,8 @@ func TestSyncPodBadHash(t *testing.T) {
 			},
 		},
 	}
-	kubelet.pods = append(kubelet.pods, bound)
+	pods := []api.Pod{bound}
+	kubelet.podManager.SetPods(pods)
 	err := kubelet.syncPod(&bound, false, dockerContainers)
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
@@ -1002,7 +1011,8 @@ func TestSyncPodUnhealthy(t *testing.T) {
 			},
 		},
 	}
-	kubelet.pods = append(kubelet.pods, bound)
+	pods := []api.Pod{bound}
+	kubelet.podManager.SetPods(pods)
 	err := kubelet.syncPod(&bound, false, dockerContainers)
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
@@ -1692,7 +1702,8 @@ func TestSyncPodEventHandlerFails(t *testing.T) {
 			},
 		},
 	}
-	kubelet.pods = append(kubelet.pods, bound)
+	pods := []api.Pod{bound}
+	kubelet.podManager.SetPods(pods)
 	err := kubelet.syncPod(&bound, false, dockerContainers)
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
@@ -2868,7 +2879,7 @@ func TestHandlePortConflicts(t *testing.T) {
 	}
 
 	// Check if we can retrieve the pod status from GetPodStatus().
-	kl.pods = pods
+	kl.podManager.SetPods(pods)
 	status, err := kl.GetPodStatus(conflictedPodName, "")
 	if err != nil {
 		t.Fatalf("unable to retrieve pod status for pod %q: #v.", conflictedPodName, err)
@@ -2921,7 +2932,7 @@ func TestHandleNodeSelector(t *testing.T) {
 	}
 
 	// Check if we can retrieve the pod status from GetPodStatus().
-	kl.pods = pods
+	kl.podManager.SetPods(pods)
 	status, err := kl.GetPodStatus(notfittingPodName, "")
 	if err != nil {
 		t.Fatalf("unable to retrieve pod status for pod %q: #v.", notfittingPodName, err)
@@ -2980,7 +2991,7 @@ func TestHandleMemExceeded(t *testing.T) {
 	}
 
 	// Check if we can retrieve the pod status from GetPodStatus().
-	kl.pods = pods
+	kl.podManager.SetPods(pods)
 	status, err := kl.GetPodStatus(notfittingPodName, "")
 	if err != nil {
 		t.Fatalf("unable to retrieve pod status for pod %q: #v.", notfittingPodName, err)
@@ -3232,7 +3243,8 @@ func TestCreateMirrorPod(t *testing.T) {
 			},
 		},
 	}
-	kl.pods = append(kl.pods, pod)
+	pods := []api.Pod{pod}
+	kl.podManager.SetPods(pods)
 	hasMirrorPod := false
 	err := kl.syncPod(&pod, hasMirrorPod, dockertools.DockerContainers{})
 	if err != nil {
@@ -3357,7 +3369,7 @@ func TestGetContainerInfoForMirrorPods(t *testing.T) {
 		},
 	}
 
-	kubelet.pods, kubelet.mirrorPods = filterAndCategorizePods(pods)
+	kubelet.podManager.SetPods(pods)
 	// Use the mirror pod UID to retrieve the stats.
 	stats, err := kubelet.GetContainerInfo("qux_ns", "5678", "foo", cadvisorReq)
 	if err != nil {

pkg/kubelet/mirror_manager.go

@@ -85,14 +85,6 @@ func (self *basicMirrorManager) DeleteMirrorPod(podFullName string) error {
 	return nil
 }
 
-// Delete all orphaned mirror pods.
-func deleteOrphanedMirrorPods(mirrorPods mirrorPods, manager mirrorManager) {
-	podFullNames := mirrorPods.GetOrphanedMirrorPodNames()
-	for _, podFullName := range podFullNames {
-		manager.DeleteMirrorPod(podFullName)
-	}
-}
-
 // Helper functions.
 func getPodSource(pod *api.Pod) (string, error) {
 	if pod.Annotations != nil {

pkg/kubelet/pod_manager.go

@@ -0,0 +1,199 @@
+/*
+Copyright 2015 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 (
+	"sync"
+
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/client"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/kubelet/metrics"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/types"
+	"github.com/golang/glog"
+)
+
+type podManager interface {
+	UpdatePods(u PodUpdate, podSyncTypes map[types.UID]metrics.SyncPodType)
+	GetPods() ([]api.Pod, mirrorPods)
+	GetPodByName(namespace, name string) (*api.Pod, bool)
+	GetPodByFullName(podFullName string) (*api.Pod, bool)
+	TranslatePodUID(uid types.UID) types.UID
+	DeleteOrphanedMirrorPods(mirrorPods *mirrorPods)
+	SetPods(pods []api.Pod)
+	mirrorManager
+}
+
+type basicPodManager struct {
+	// Protects all internal pod storage/mappings.
+	lock sync.RWMutex
+	pods []api.Pod
+	// Record the set of mirror pods (see mirror_manager.go for more details);
+	// similar to pods, this is not immutable and is protected by the same podLock.
+	// Note that basicPodManager.pods do not contain mirror pods as they are
+	// filtered out beforehand.
+	mirrorPods mirrorPods
+
+	// A mirror pod manager which provides helper functions.
+	mirrorManager mirrorManager
+}
+
+func newBasicPodManager(apiserverClient client.Interface) *basicPodManager {
+	podManager := &basicPodManager{}
+	podManager.mirrorManager = newBasicMirrorManager(apiserverClient)
+	podManager.mirrorPods = *newMirrorPods()
+	podManager.pods = []api.Pod{}
+	return podManager
+}
+
+// This method is used only for testing to quickly set the internal pods.
+func (self *basicPodManager) SetPods(pods []api.Pod) {
+	self.pods, self.mirrorPods = filterAndCategorizePods(pods)
+}
+
+// Update the internal pods with those provided by the update.
+// Records new and updated pods in newPods and updatedPods.
+func (self *basicPodManager) UpdatePods(u PodUpdate, podSyncTypes map[types.UID]metrics.SyncPodType) {
+	self.lock.Lock()
+	defer self.lock.Unlock()
+	switch u.Op {
+	case SET:
+		glog.V(3).Infof("SET: Containers changed")
+		newPods, newMirrorPods := filterAndCategorizePods(u.Pods)
+
+		// Store the new pods. Don't worry about filtering host ports since those
+		// pods will never be looked up.
+		existingPods := make(map[types.UID]struct{})
+		for i := range self.pods {
+			existingPods[self.pods[i].UID] = struct{}{}
+		}
+		for _, pod := range newPods {
+			if _, ok := existingPods[pod.UID]; !ok {
+				podSyncTypes[pod.UID] = metrics.SyncPodCreate
+			}
+		}
+		// Actually update the pods.
+		self.pods = newPods
+		self.mirrorPods = newMirrorPods
+	case UPDATE:
+		glog.V(3).Infof("Update: Containers changed")
+
+		// Store the updated pods. Don't worry about filtering host ports since those
+		// pods will never be looked up.
+		for i := range u.Pods {
+			podSyncTypes[u.Pods[i].UID] = metrics.SyncPodUpdate
+		}
+		allPods := updatePods(u.Pods, self.pods)
+		self.pods, self.mirrorPods = filterAndCategorizePods(allPods)
+	default:
+		panic("syncLoop does not support incremental changes")
+	}
+
+	// Mark all remaining pods as sync.
+	for i := range self.pods {
+		if _, ok := podSyncTypes[self.pods[i].UID]; !ok {
+			podSyncTypes[u.Pods[i].UID] = metrics.SyncPodSync
+		}
+	}
+}
+
+func updatePods(changed []api.Pod, current []api.Pod) []api.Pod {
+	updated := []api.Pod{}
+	m := map[types.UID]*api.Pod{}
+	for i := range changed {
+		pod := &changed[i]
+		m[pod.UID] = pod
+	}
+
+	for i := range current {
+		pod := &current[i]
+		if m[pod.UID] != nil {
+			updated = append(updated, *m[pod.UID])
+			glog.V(4).Infof("pod with UID: %q has a new spec %+v", pod.UID, *m[pod.UID])
+		} else {
+			updated = append(updated, *pod)
+			glog.V(4).Infof("pod with UID: %q stay with the same spec %+v", pod.UID, *pod)
+		}
+	}
+
+	return updated
+}
+
+// GetPods returns all pods bound to the kubelet and their spec, and the mirror
+// pod map.
+func (self *basicPodManager) GetPods() ([]api.Pod, mirrorPods) {
+	self.lock.RLock()
+	defer self.lock.RUnlock()
+	return append([]api.Pod{}, self.pods...), self.mirrorPods
+}
+
+// GetPodByName provides the first pod that matches namespace and name, as well
+// as whether the pod was found.
+func (self *basicPodManager) GetPodByName(namespace, name string) (*api.Pod, bool) {
+	self.lock.RLock()
+	defer self.lock.RUnlock()
+	for i := range self.pods {
+		pod := self.pods[i]
+		if pod.Namespace == namespace && pod.Name == name {
+			return &pod, true
+		}
+	}
+	return nil, false
+}
+
+func (self *basicPodManager) GetPodByFullName(podFullName string) (*api.Pod, bool) {
+	name, namespace, err := ParsePodFullName(podFullName)
+	if err != nil {
+		return nil, false
+	}
+	return self.GetPodByName(namespace, name)
+}
+
+// If the UID belongs to a mirror pod, maps it to the UID of its static pod.
+// Otherwise, return the original UID. All public-facing functions should
+// perform this translation for UIDs because user may provide a mirror pod UID,
+// which is not recognized by internal Kubelet functions.
+func (self *basicPodManager) TranslatePodUID(uid types.UID) types.UID {
+	if uid == "" {
+		return uid
+	}
+
+	self.lock.RLock()
+	defer self.lock.RUnlock()
+	staticUID, ok := self.mirrorPods.GetStaticUID(uid)
+	if ok {
+		return staticUID
+	} else {
+		return uid
+	}
+}
+
+// Delete all orphaned mirror pods. This method doesn't acquire the lock
+// because it assumes the a copy of the mirrorPod is passed as an argument.
+func (self *basicPodManager) DeleteOrphanedMirrorPods(mirrorPods *mirrorPods) {
+	podFullNames := mirrorPods.GetOrphanedMirrorPodNames()
+	for _, podFullName := range podFullNames {
+		self.mirrorManager.DeleteMirrorPod(podFullName)
+	}
+}
+
+func (self *basicPodManager) CreateMirrorPod(pod api.Pod, hostname string) error {
+	return self.mirrorManager.CreateMirrorPod(pod, hostname)
+}
+
+func (self *basicPodManager) DeleteMirrorPod(podFullName string) error {
+	return self.mirrorManager.DeleteMirrorPod(podFullName)
+}

pkg/kubelet/pod_manager_test.go

@@ -0,0 +1,25 @@
+/*
+Copyright 2015 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
+
+// Stub out mirror manager for testing purpose.
+func newFakePodManager() (*basicPodManager, *fakeMirrorManager) {
+	podManager := newBasicPodManager(nil)
+	fakeMirrorManager := newFakeMirrorMananger()
+	podManager.mirrorManager = fakeMirrorManager
+	return podManager, fakeMirrorManager
+}