// Kill all containers in a pod.  Returns the number of containers deleted and an error if one occurs.
func (kl *Kubelet) killContainersInPod(pod *api.BoundPod, dockerContainers dockertools.DockerContainers) (int, error) {
	podFullName := GetPodFullName(pod)

	count := 0
	errs := make(chan error, len(pod.Spec.Containers))
	wg := sync.WaitGroup{}
	for _, container := range pod.Spec.Containers {
		// TODO: Consider being more aggressive: kill all containers with this pod UID, period.
		if dockerContainer, found, _ := dockerContainers.FindPodContainer(podFullName, pod.UID, container.Name); found {
			count++
			wg.Add(1)
			go func() {
				err := kl.killContainer(dockerContainer)
				if err != nil {
					glog.Errorf("Failed to delete container: %v; Skipping pod %q", err, podFullName)
					errs <- err
				}
				wg.Done()
			}()
		}
	}
	wg.Wait()
	close(errs)
	if len(errs) > 0 {
		errList := []error{}
		for err := range errs {
			errList = append(errList, err)
		}
		return -1, fmt.Errorf("failed to delete containers (%v)", errList)
	}
	return count, nil
}

// Delete all containers in a pod (except the network container) returns the number of containers deleted
// and an error if one occurs.
func (kl *Kubelet) deleteAllContainers(pod *Pod, podFullName string, dockerContainers dockertools.DockerContainers) (int, error) {
	count := 0
	errs := make(chan error, len(pod.Manifest.Containers))
	wg := sync.WaitGroup{}
	for _, container := range pod.Manifest.Containers {
		if dockerContainer, found, _ := dockerContainers.FindPodContainer(podFullName, pod.Manifest.UUID, container.Name); found {
			count++
			wg.Add(1)
			go func() {
				err := kl.killContainer(dockerContainer)
				if err != nil {
					glog.Errorf("Failed to delete container. (%v)  Skipping pod %s", err, podFullName)
					errs <- err
				}
				wg.Done()
			}()
		}
	}
	wg.Wait()
	close(errs)
	if len(errs) > 0 {
		errList := []error{}
		for err := range errs {
			errList = append(errList, err)
		}
		return -1, fmt.Errorf("failed to delete containers (%v)", errList)
	}
	return count, nil
}

// isPodRunning returns true if all containers of a manifest are running.
func (kl *Kubelet) isPodRunning(pod api.BoundPod, dockerContainers dockertools.DockerContainers) (bool, error) {
	for _, container := range pod.Spec.Containers {
		dockerContainer, found, _ := dockerContainers.FindPodContainer(GetPodFullName(&pod), pod.UID, container.Name)
		if !found {
			glog.Infof("container %q not found", container.Name)
			return false, nil
		}
		inspectResult, err := kl.dockerClient.InspectContainer(dockerContainer.ID)
		if err != nil {
			glog.Infof("failed to inspect container %q: %v", container.Name, err)
			return false, err
		}
		if !inspectResult.State.Running {
			glog.Infof("container %q not running: %#v", container.Name, inspectResult.State)
			return false, nil
		}
	}
	return true, nil
}

func (kl *Kubelet) syncPod(pod *api.BoundPod, dockerContainers dockertools.DockerContainers) error {
	podFullName := GetPodFullName(pod)
	uuid := pod.UID
	containersToKeep := make(map[dockertools.DockerID]empty)
	killedContainers := make(map[dockertools.DockerID]empty)
	glog.V(4).Infof("Syncing Pod, podFullName: %q, uuid: %q", podFullName, uuid)

	// Make sure we have a network container
	var netID dockertools.DockerID
	if netDockerContainer, found, _ := dockerContainers.FindPodContainer(podFullName, uuid, networkContainerName); found {
		netID = dockertools.DockerID(netDockerContainer.ID)
	} else {
		glog.V(2).Infof("Network container doesn't exist for pod %q, killing and re-creating the pod", podFullName)
		count, err := kl.killContainersInPod(pod, dockerContainers)
		if err != nil {
			return err
		}
		netID, err = kl.createNetworkContainer(pod)
		if err != nil {
			glog.Errorf("Failed to introspect network container: %v; Skipping pod %q", err, podFullName)
			return err
		}
		if count > 0 {
			// Re-list everything, otherwise we'll think we're ok.
			dockerContainers, err = dockertools.GetKubeletDockerContainers(kl.dockerClient, false)
			if err != nil {
				glog.Errorf("Error listing containers %#v", dockerContainers)
				return err
			}
		}
	}
	containersToKeep[netID] = empty{}

	podVolumes, err := kl.mountExternalVolumes(pod)
	if err != nil {
		glog.Errorf("Unable to mount volumes for pod %q: %v; skipping pod", podFullName, err)
		return err
	}

	podStatus := api.PodStatus{}
	info, err := kl.GetPodInfo(podFullName, uuid)
	if err != nil {
		glog.Errorf("Unable to get pod with name %q and uuid %q info, health checks may be invalid", podFullName, uuid)
	}
	netInfo, found := info[networkContainerName]
	if found {
		podStatus.PodIP = netInfo.PodIP
	}

	for _, container := range pod.Spec.Containers {
		expectedHash := dockertools.HashContainer(&container)
		if dockerContainer, found, hash := dockerContainers.FindPodContainer(podFullName, uuid, container.Name); found {
			containerID := dockertools.DockerID(dockerContainer.ID)
			glog.V(3).Infof("pod %q container %q exists as %v", podFullName, container.Name, containerID)

			// look for changes in the container.
			if hash == 0 || hash == expectedHash {
				// TODO: This should probably be separated out into a separate goroutine.
				healthy, err := kl.healthy(podFullName, uuid, podStatus, container, dockerContainer)
				if err != nil {
					glog.V(1).Infof("health check errored: %v", err)
					containersToKeep[containerID] = empty{}
					continue
				}
				if healthy == health.Healthy {
					containersToKeep[containerID] = empty{}
					continue
				}
				glog.V(1).Infof("pod %q container %q is unhealthy. Container will be killed and re-created.", podFullName, container.Name, healthy)
			} else {
				glog.V(1).Infof("pod %q container %q hash changed (%d vs %d). Container will be killed and re-created.", podFullName, container.Name, hash, expectedHash)
			}
			if err := kl.killContainer(dockerContainer); err != nil {
				glog.V(1).Infof("Failed to kill container %q: %v", dockerContainer.ID, err)
				continue
			}
			killedContainers[containerID] = empty{}

			// Also kill associated network container
			if netContainer, found, _ := dockerContainers.FindPodContainer(podFullName, uuid, networkContainerName); found {
				if err := kl.killContainer(netContainer); err != nil {
					glog.V(1).Infof("Failed to kill network container %q: %v", netContainer.ID, err)
					continue
				}
			}
		}

		// Check RestartPolicy for container
		recentContainers, err := dockertools.GetRecentDockerContainersWithNameAndUUID(kl.dockerClient, podFullName, uuid, container.Name)
		if err != nil {
			glog.Errorf("Error listing recent containers with name and uuid:%s--%s--%s", podFullName, uuid, container.Name)
			// TODO(dawnchen): error handling here?
		}

		if len(recentContainers) > 0 && pod.Spec.RestartPolicy.Always == nil {
			if pod.Spec.RestartPolicy.Never != nil {
				glog.V(3).Infof("Already ran container with name %s--%s--%s, do nothing",
					podFullName, uuid, container.Name)
				continue
			}
//.........这里部分代码省略.........

func (kl *Kubelet) syncPod(pod *Pod, dockerContainers dockertools.DockerContainers) error {
	podFullName := GetPodFullName(pod)
	uuid := pod.Manifest.UUID
	containersToKeep := make(map[dockertools.DockerID]empty)
	killedContainers := make(map[dockertools.DockerID]empty)

	// Make sure we have a network container
	var netID dockertools.DockerID
	if networkDockerContainer, found, _ := dockerContainers.FindPodContainer(podFullName, uuid, networkContainerName); found {
		netID = dockertools.DockerID(networkDockerContainer.ID)
	} else {
		glog.Infof("Network container doesn't exist, creating")
		count, err := kl.deleteAllContainers(pod, podFullName, dockerContainers)
		if err != nil {
			return err
		}
		dockerNetworkID, err := kl.createNetworkContainer(pod)
		if err != nil {
			glog.Errorf("Failed to introspect network container. (%v)  Skipping pod %s", err, podFullName)
			return err
		}
		netID = dockerNetworkID
		if count > 0 {
			// relist everything, otherwise we'll think we're ok
			dockerContainers, err = dockertools.GetKubeletDockerContainers(kl.dockerClient)
			if err != nil {
				glog.Errorf("Error listing containers %#v", dockerContainers)
				return err
			}
		}
	}
	containersToKeep[netID] = empty{}

	podVolumes, err := kl.mountExternalVolumes(&pod.Manifest)
	if err != nil {
		glog.Errorf("Unable to mount volumes for pod %s: (%v) Skipping pod.", podFullName, err)
		return err
	}

	podState := api.PodState{Manifest: api.ContainerManifest{UUID: uuid}}
	info, err := kl.GetPodInfo(podFullName, uuid)
	if err != nil {
		glog.Errorf("Unable to get pod with name %s and uuid %s info, health checks may be invalid.",
			podFullName, uuid)
	}
	netInfo, found := info[networkContainerName]
	if found && netInfo.NetworkSettings != nil {
		podState.PodIP = netInfo.NetworkSettings.IPAddress
	}

	for _, container := range pod.Manifest.Containers {
		expectedHash := dockertools.HashContainer(&container)
		if dockerContainer, found, hash := dockerContainers.FindPodContainer(podFullName, uuid, container.Name); found {
			containerID := dockertools.DockerID(dockerContainer.ID)
			glog.V(1).Infof("pod %s container %s exists as %v", podFullName, container.Name, containerID)

			// look for changes in the container.
			if hash == 0 || hash == expectedHash {
				// TODO: This should probably be separated out into a separate goroutine.
				healthy, err := kl.healthy(podFullName, podState, container, dockerContainer)
				if err != nil {
					glog.V(1).Infof("health check errored: %v", err)
					containersToKeep[containerID] = empty{}
					continue
				}
				if healthy == health.Healthy {
					containersToKeep[containerID] = empty{}
					continue
				}
				glog.V(1).Infof("pod %s container %s is unhealthy.", podFullName, container.Name, healthy)
			} else {
				glog.V(1).Infof("container hash changed %d vs %d.", hash, expectedHash)
			}
			if err := kl.killContainer(dockerContainer); err != nil {
				glog.V(1).Infof("Failed to kill container %s: %v", dockerContainer.ID, err)
				continue
			}
			killedContainers[containerID] = empty{}
		}

		// Check RestartPolicy for container
		recentContainers, err := dockertools.GetRecentDockerContainersWithNameAndUUID(kl.dockerClient, podFullName, uuid, container.Name)
		if err != nil {
			glog.Errorf("Error listing recent containers with name and uuid:%s--%s--%s", podFullName, uuid, container.Name)
			// TODO(dawnchen): error handling here?
		}

		if len(recentContainers) > 0 && pod.Manifest.RestartPolicy.Always == nil {
			if pod.Manifest.RestartPolicy.Never != nil {
				glog.Infof("Already ran container with name %s--%s--%s, do nothing",
					podFullName, uuid, container.Name)
				continue
			}
			if pod.Manifest.RestartPolicy.OnFailure != nil {
				// Check the exit code of last run
				if recentContainers[0].State.ExitCode == 0 {
					glog.Infof("Already successfully ran container with name %s--%s--%s, do nothing",
						podFullName, uuid, container.Name)
					continue
				}
//.........这里部分代码省略.........