Start using PodSyncResult in dockertools

pkg/kubelet/dockertools/manager.go

@@ -1223,16 +1223,23 @@ func (dm *DockerManager) GetContainerIP(containerID, interfaceName string) (stri
 // TODO(random-liu): After using pod status for KillPod(), we can also remove the kubernetesPodLabel, because all the needed information should have
 // been extract from new labels and stored in pod status.
 func (dm *DockerManager) KillPod(pod *api.Pod, runningPod kubecontainer.Pod) error {
-	// Send the kills in parallel since they may take a long time. Len + 1 since there
+	result := dm.killPodWithSyncResult(pod, runningPod)
-	// can be Len errors + the networkPlugin teardown error.
+	return result.Error()
-	errs := make(chan error, len(runningPod.Containers)+1)
+}
+
+// TODO(random-liu): This is just a temporary function, will be removed when we acturally add PodSyncResult
+// NOTE(random-liu): The pod passed in could be *nil* when kubelet restarted.
+func (dm *DockerManager) killPodWithSyncResult(pod *api.Pod, runningPod kubecontainer.Pod) (result kubecontainer.PodSyncResult) {
+	// Send the kills in parallel since they may take a long time.
+	// There may be len(runningPod.Containers) or len(runningPod.Containers)-1 of result in the channel
+	containerResults := make(chan *kubecontainer.SyncResult, len(runningPod.Containers))
 	wg := sync.WaitGroup{}
 	var (
 		networkContainer *kubecontainer.Container
 		networkSpec      *api.Container
 	)
+	wg.Add(len(runningPod.Containers))
 	for _, container := range runningPod.Containers {
-		wg.Add(1)
 		go func(container *kubecontainer.Container) {
 			defer util.HandleCrash()
 			defer wg.Done()
@@ -1257,33 +1264,36 @@ func (dm *DockerManager) KillPod(pod *api.Pod, runningPod kubecontainer.Pod) err
 				return
 			}
 
+			killContainerResult := kubecontainer.NewSyncResult(kubecontainer.KillContainer, container.Name)
 			err := dm.KillContainerInPod(container.ID, containerSpec, pod, "Need to kill pod.")
 			if err != nil {
+				killContainerResult.Fail(kubecontainer.ErrKillContainer, err.Error())
 				glog.Errorf("Failed to delete container: %v; Skipping pod %q", err, runningPod.ID)
-				errs <- err
 			}
+			containerResults <- killContainerResult
 		}(container)
 	}
 	wg.Wait()
+	close(containerResults)
+	for containerResult := range containerResults {
+		result.AddSyncResult(containerResult)
+	}
 	if networkContainer != nil {
+		teardownNetworkResult := kubecontainer.NewSyncResult(kubecontainer.TeardownNetwork, kubecontainer.BuildPodFullName(runningPod.Name, runningPod.Namespace))
+		result.AddSyncResult(teardownNetworkResult)
 		if err := dm.networkPlugin.TearDownPod(runningPod.Namespace, runningPod.Name, kubecontainer.DockerID(networkContainer.ID.ID)); err != nil {
-			glog.Errorf("Failed tearing down the infra container: %v", err)
+			message := fmt.Sprintf("Failed to teardown network for pod %q using network plugins %q: %v", runningPod.ID, dm.networkPlugin.Name(), err)
-			errs <- err
+			teardownNetworkResult.Fail(kubecontainer.ErrTeardownNetwork, message)
+			glog.Error(message)
 		}
+		killContainerResult := kubecontainer.NewSyncResult(kubecontainer.KillContainer, networkContainer.Name)
+		result.AddSyncResult(killContainerResult)
 		if err := dm.KillContainerInPod(networkContainer.ID, networkSpec, pod, "Need to kill pod."); err != nil {
+			killContainerResult.Fail(kubecontainer.ErrKillContainer, err.Error())
 			glog.Errorf("Failed to delete container: %v; Skipping pod %q", err, runningPod.ID)
-			errs <- err
 		}
 	}
-	close(errs)
+	return
-	if len(errs) > 0 {
-		errList := []error{}
-		for err := range errs {
-			errList = append(errList, err)
-		}
-		return fmt.Errorf("failed to delete containers (%v)", errList)
-	}
-	return nil
 }
 
 // KillContainerInPod kills a container in the pod. It must be passed either a container ID or a container and pod,
@@ -1559,7 +1569,8 @@ func appendToFile(filePath, stringToAppend string) error {
 }
 
 // createPodInfraContainer starts the pod infra container for a pod. Returns the docker container ID of the newly created container.
-func (dm *DockerManager) createPodInfraContainer(pod *api.Pod) (kubecontainer.DockerID, error) {
+// If any error occurs in this function, it will return a brief error and a detailed error message.
+func (dm *DockerManager) createPodInfraContainer(pod *api.Pod) (kubecontainer.DockerID, error, string) {
 	start := time.Now()
 	defer func() {
 		metrics.ContainerManagerLatency.WithLabelValues("createPodInfraContainer").Observe(metrics.SinceInMicroseconds(start))
@@ -1591,17 +1602,17 @@ func (dm *DockerManager) createPodInfraContainer(pod *api.Pod) (kubecontainer.Do
 
 	// No pod secrets for the infra container.
 	// The message isnt needed for the Infra container
-	if err, _ := dm.imagePuller.PullImage(pod, container, nil); err != nil {
+	if err, msg := dm.imagePuller.PullImage(pod, container, nil); err != nil {
-		return "", err
+		return "", err, msg
 	}
 
 	// Currently we don't care about restart count of infra container, just set it to 0.
 	id, err := dm.runContainerInPod(pod, container, netNamespace, getIPCMode(pod), getPidMode(pod), 0)
 	if err != nil {
-		return "", err
+		return "", kubecontainer.ErrRunContainer, err.Error()
 	}
 
-	return kubecontainer.DockerID(id.ID), nil
+	return kubecontainer.DockerID(id.ID), nil, ""
 }
 
 // Structure keeping information on changes that need to happen for a pod. The semantics is as follows:
@@ -1745,7 +1756,13 @@ func (dm *DockerManager) clearReasonCache(pod *api.Pod, container *api.Container
 }
 
 // Sync the running pod to match the specified desired pod.
-func (dm *DockerManager) SyncPod(pod *api.Pod, _ api.PodStatus, podStatus *kubecontainer.PodStatus, pullSecrets []api.Secret, backOff *util.Backoff) error {
+func (dm *DockerManager) SyncPod(pod *api.Pod, apiPodStatus api.PodStatus, podStatus *kubecontainer.PodStatus, pullSecrets []api.Secret, backOff *util.Backoff) error {
+	result := dm.syncPodWithSyncResult(pod, apiPodStatus, podStatus, pullSecrets, backOff)
+	return result.Error()
+}
+
+// (random-liu) This is just a temporary function, will be removed when we acturally add PodSyncEvent
+func (dm *DockerManager) syncPodWithSyncResult(pod *api.Pod, _ api.PodStatus, podStatus *kubecontainer.PodStatus, pullSecrets []api.Secret, backOff *util.Backoff) (result kubecontainer.PodSyncResult) {
 	start := time.Now()
 	defer func() {
 		metrics.ContainerManagerLatency.WithLabelValues("SyncPod").Observe(metrics.SinceInMicroseconds(start))
@@ -1753,7 +1770,8 @@ func (dm *DockerManager) SyncPod(pod *api.Pod, _ api.PodStatus, podStatus *kubec
 
 	containerChanges, err := dm.computePodContainerChanges(pod, podStatus)
 	if err != nil {
-		return err
+		result.Fail(err)
+		return
 	}
 	glog.V(3).Infof("Got container changes for pod %q: %+v", format.Pod(pod), containerChanges)
 
@@ -1773,8 +1791,10 @@ func (dm *DockerManager) SyncPod(pod *api.Pod, _ api.PodStatus, podStatus *kubec
 
 		// Killing phase: if we want to start new infra container, or nothing is running kill everything (including infra container)
 		// TODO(random-liu): We'll use pod status directly in the future
-		if err := dm.KillPod(pod, kubecontainer.ConvertPodStatusToRunningPod(podStatus)); err != nil {
+		killResult := dm.killPodWithSyncResult(pod, kubecontainer.ConvertPodStatusToRunningPod(podStatus))
-			return err
+		result.AddPodSyncResult(killResult)
+		if killResult.Error() != nil {
+			return
 		}
 	} else {
 		// Otherwise kill any running containers in this pod which are not specified as ones to keep.
@@ -1782,8 +1802,7 @@ func (dm *DockerManager) SyncPod(pod *api.Pod, _ api.PodStatus, podStatus *kubec
 		for _, containerStatus := range runningContainerStatues {
 			_, keep := containerChanges.ContainersToKeep[kubecontainer.DockerID(containerStatus.ID.ID)]
 			if !keep {
-				// NOTE(random-liu): Just log ID or log container status here?
+				glog.V(3).Infof("Killing unwanted container %q(id=%q) for pod %q", containerStatus.Name, containerStatus.ID, format.Pod(pod))
-				glog.V(3).Infof("Killing unwanted container %+v", containerStatus)
 				// attempt to find the appropriate container policy
 				var podContainer *api.Container
 				var killMessage string
@@ -1794,9 +1813,12 @@ func (dm *DockerManager) SyncPod(pod *api.Pod, _ api.PodStatus, podStatus *kubec
 						break
 					}
 				}
+				killContainerResult := kubecontainer.NewSyncResult(kubecontainer.KillContainer, containerStatus.Name)
+				result.AddSyncResult(killContainerResult)
 				if err := dm.KillContainerInPod(containerStatus.ID, podContainer, pod, killMessage); err != nil {
-					glog.Errorf("Error killing container: %v", err)
+					killContainerResult.Fail(kubecontainer.ErrKillContainer, err.Error())
-					return err
+					glog.Errorf("Error killing container %q(id=%q) for pod %q: %v", containerStatus.Name, containerStatus.ID, format.Pod(pod), err)
+					return
 				}
 			}
 		}
@@ -1806,31 +1828,45 @@ func (dm *DockerManager) SyncPod(pod *api.Pod, _ api.PodStatus, podStatus *kubec
 	podInfraContainerID := containerChanges.InfraContainerId
 	if containerChanges.StartInfraContainer && (len(containerChanges.ContainersToStart) > 0) {
 		glog.V(4).Infof("Creating pod infra container for %q", format.Pod(pod))
-		podInfraContainerID, err = dm.createPodInfraContainer(pod)
+		startContainerResult := kubecontainer.NewSyncResult(kubecontainer.StartContainer, PodInfraContainerName)
+		result.AddSyncResult(startContainerResult)
+		var msg string
+		podInfraContainerID, err, msg = dm.createPodInfraContainer(pod)
 		if err != nil {
+			startContainerResult.Fail(err, msg)
 			glog.Errorf("Failed to create pod infra container: %v; Skipping pod %q", err, format.Pod(pod))
-			return err
+			return
 		}
 
+		setupNetworkResult := kubecontainer.NewSyncResult(kubecontainer.SetupNetwork, kubecontainer.GetPodFullName(pod))
+		result.AddSyncResult(setupNetworkResult)
 		// Call the networking plugin
 		err = dm.networkPlugin.SetUpPod(pod.Namespace, pod.Name, podInfraContainerID)
 		if err != nil {
-			message := fmt.Sprintf("Failed to setup networking for pod %q using network plugins: %v; Skipping pod", format.Pod(pod), err)
+			// TODO: (random-liu) There shouldn't be "Skipping pod" in sync result message
+			message := fmt.Sprintf("Failed to setup network for pod %q using network plugins %q: %v; Skipping pod", format.Pod(pod), dm.networkPlugin.Name(), err)
+			setupNetworkResult.Fail(kubecontainer.ErrSetupNetwork, message)
 			glog.Error(message)
+
 			// Delete infra container
+			killContainerResult := kubecontainer.NewSyncResult(kubecontainer.KillContainer, PodInfraContainerName)
+			result.AddSyncResult(killContainerResult)
 			if delErr := dm.KillContainerInPod(kubecontainer.ContainerID{
 				ID:   string(podInfraContainerID),
 				Type: "docker"}, nil, pod, message); delErr != nil {
+				killContainerResult.Fail(kubecontainer.ErrKillContainer, delErr.Error())
 				glog.Warningf("Clear infra container failed for pod %q: %v", format.Pod(pod), delErr)
 			}
-			return err
+			return
 		}
 
 		// Setup the host interface unless the pod is on the host's network (FIXME: move to networkPlugin when ready)
-		podInfraContainer, err := dm.client.InspectContainer(string(podInfraContainerID))
+		var podInfraContainer *docker.Container
+		podInfraContainer, err = dm.client.InspectContainer(string(podInfraContainerID))
 		if err != nil {
 			glog.Errorf("Failed to inspect pod infra container: %v; Skipping pod %q", err, format.Pod(pod))
-			return err
+			result.Fail(err)
+			return
 		}
 		if !(pod.Spec.SecurityContext != nil && pod.Spec.SecurityContext.HostNetwork) {
 			if err = hairpin.SetUpContainer(podInfraContainer.State.Pid, "eth0"); err != nil {
@@ -1843,28 +1879,35 @@ func (dm *DockerManager) SyncPod(pod *api.Pod, _ api.PodStatus, podStatus *kubec
 		pod.Status.PodIP = dm.determineContainerIP(pod.Name, pod.Namespace, podInfraContainer)
 	}
 
-	containersStarted := 0
 	// Start everything
 	for idx := range containerChanges.ContainersToStart {
 		container := &pod.Spec.Containers[idx]
+		startContainerResult := kubecontainer.NewSyncResult(kubecontainer.StartContainer, container.Name)
+		result.AddSyncResult(startContainerResult)
 
 		// containerChanges.StartInfraContainer causes the containers to be restarted for config reasons
 		// ignore backoff
-		if !containerChanges.StartInfraContainer && dm.doBackOff(pod, container, podStatus, backOff) {
+		if !containerChanges.StartInfraContainer {
+			isInBackOff, err, msg := dm.doBackOff(pod, container, podStatus, backOff)
+			if isInBackOff {
+				startContainerResult.Fail(err, msg)
 				glog.V(4).Infof("Backing Off restarting container %+v in pod %v", container, format.Pod(pod))
 				continue
 			}
+		}
 		glog.V(4).Infof("Creating container %+v in pod %v", container, format.Pod(pod))
 		err, msg := dm.imagePuller.PullImage(pod, container, pullSecrets)
 		if err != nil {
+			startContainerResult.Fail(err, msg)
 			dm.updateReasonCache(pod, container, err.Error(), errors.New(msg))
 			continue
 		}
 
 		if container.SecurityContext != nil && container.SecurityContext.RunAsNonRoot != nil && *container.SecurityContext.RunAsNonRoot {
 			err := dm.verifyNonRoot(container)
-			dm.updateReasonCache(pod, container, "VerifyNonRootError", err)
+			dm.updateReasonCache(pod, container, kubecontainer.ErrVerifyNonRoot.Error(), err)
 			if err != nil {
+				startContainerResult.Fail(kubecontainer.ErrVerifyNonRoot, err.Error())
 				glog.Errorf("Error running pod %q container %q: %v", format.Pod(pod), container.Name, err)
 				continue
 			}
@@ -1885,20 +1928,16 @@ func (dm *DockerManager) SyncPod(pod *api.Pod, _ api.PodStatus, podStatus *kubec
 		_, err = dm.runContainerInPod(pod, container, namespaceMode, namespaceMode, getPidMode(pod), restartCount)
 		dm.updateReasonCache(pod, container, kubecontainer.ErrRunContainer.Error(), err)
 		if err != nil {
+			startContainerResult.Fail(kubecontainer.ErrRunContainer, err.Error())
 			// TODO(bburns) : Perhaps blacklist a container after N failures?
 			glog.Errorf("Error running pod %q container %q: %v", format.Pod(pod), container.Name, err)
 			continue
 		}
-		containersStarted++
 		// Successfully started the container; clear the entry in the failure
 		// reason cache.
 		dm.clearReasonCache(pod, container)
 	}
-
+	return
-	if containersStarted != len(containerChanges.ContainersToStart) {
-		return fmt.Errorf("not all containers have started: %d != %d", containersStarted, len(containerChanges.ContainersToStart))
-	}
-	return nil
 }
 
 // verifyNonRoot returns an error if the container or image will run as the root user.
@@ -1960,7 +1999,10 @@ func getUidFromUser(id string) string {
 	return id
 }
 
-func (dm *DockerManager) doBackOff(pod *api.Pod, container *api.Container, podStatus *kubecontainer.PodStatus, backOff *util.Backoff) bool {
+// If all instances of a container are garbage collected, doBackOff will also return false, which means the container may be restarted before the
+// backoff deadline. However, because that won't cause error and the chance is really slim, we can just ignore it for now.
+// If a container is still in backoff, the function will return a brief backoff error and a detailed error message.
+func (dm *DockerManager) doBackOff(pod *api.Pod, container *api.Container, podStatus *kubecontainer.PodStatus, backOff *util.Backoff) (bool, error, string) {
 	containerStatus := podStatus.FindContainerStatusByName(container.Name)
 	if containerStatus != nil && containerStatus.State == kubecontainer.ContainerStateExited && !containerStatus.FinishedAt.IsZero() {
 		ts := containerStatus.FinishedAt
@@ -1978,13 +2020,13 @@ func (dm *DockerManager) doBackOff(pod *api.Pod, container *api.Container, podSt
 			err := fmt.Errorf("Back-off %s restarting failed container=%s pod=%s", backOff.Get(stableName), container.Name, format.Pod(pod))
 			dm.updateReasonCache(pod, container, kubecontainer.ErrCrashLoopBackOff.Error(), err)
 			glog.Infof("%s", err.Error())
-			return true
+			return true, kubecontainer.ErrCrashLoopBackOff, err.Error()
 		}
 		backOff.Next(stableName, ts)
 
 	}
 	dm.clearReasonCache(pod, container)
-	return false
+	return false, nil, ""
 }
 
 // getPidMode returns the pid mode to use on the docker container based on pod.Spec.HostPID.