Move more things into docker label, and add label test

pkg/kubelet/dockertools/labels.go

@@ -21,6 +21,8 @@ import (
 
 	"github.com/golang/glog"
 	"k8s.io/kubernetes/pkg/api"
+	kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
+	"k8s.io/kubernetes/pkg/types"
 )
 
 // This file contains all docker label related constants and functions, including:
@@ -30,52 +32,79 @@ import (
 const (
 	kubernetesPodNameLabel      = "io.kubernetes.pod.name"
 	kubernetesPodNamespaceLabel = "io.kubernetes.pod.namespace"
-	kubernetesPodUID            = "io.kubernetes.pod.uid"
+	kubernetesPodUIDLabel       = "io.kubernetes.pod.uid"
 
-	kubernetesContainerRestartCountLabel      = "io.kubernetes.container.restartCount"
-	kubernetesContainerTerminationMessagePath = "io.kubernetes.container.terminationMessagePath"
+	kubernetesContainerNameLabel                   = "io.kubernetes.container.name"
+	kubernetesContainerHashLabel                   = "io.kubernetes.container.hash"
+	kubernetesContainerRestartCountLabel           = "io.kubernetes.container.restartCount"
+	kubernetesContainerTerminationMessagePathLabel = "io.kubernetes.container.terminationMessagePath"
 
 	kubernetesPodLabel                    = "io.kubernetes.pod.data"
 	kubernetesTerminationGracePeriodLabel = "io.kubernetes.pod.terminationGracePeriod"
 	kubernetesContainerLabel              = "io.kubernetes.container.name"
 )
 
+// Container information which has been labelled on each docker container
+type labelledContainerInfo struct {
+	PodName                string
+	PodNamespace           string
+	PodUID                 types.UID
+	Name                   string
+	Hash                   string
+	RestartCount           int
+	TerminationMessagePath string
+}
+
 func newLabels(container *api.Container, pod *api.Pod, restartCount int) map[string]string {
 	// TODO (random-liu) Move more label initialization here
 	labels := map[string]string{}
 	labels[kubernetesPodNameLabel] = pod.Name
 	labels[kubernetesPodNamespaceLabel] = pod.Namespace
-	labels[kubernetesPodUID] = string(pod.UID)
+	labels[kubernetesPodUIDLabel] = string(pod.UID)
 
+	labels[kubernetesContainerNameLabel] = container.Name
+	labels[kubernetesContainerHashLabel] = strconv.FormatUint(kubecontainer.HashContainer(container), 16)
 	labels[kubernetesContainerRestartCountLabel] = strconv.Itoa(restartCount)
-	labels[kubernetesContainerTerminationMessagePath] = container.TerminationMessagePath
+	labels[kubernetesContainerTerminationMessagePathLabel] = container.TerminationMessagePath
 
 	return labels
 }
 
-func getRestartCountFromLabel(labels map[string]string) (restartCount int, err error) {
-	if restartCountString, found := labels[kubernetesContainerRestartCountLabel]; found {
-		restartCount, err = strconv.Atoi(restartCountString)
-		if err != nil {
-			// This really should not happen. Just set restartCount to 0 to handle this abnormal case
-			restartCount = 0
-		}
-	} else {
-		// Get restartCount from docker label. If there is no restart count label in a container,
-		// it should be an old container or an invalid container, we just set restart count to 0.
-		// Do not report error, because there should be many old containers without this label now
-		glog.V(3).Infof("Container doesn't have label %s, it may be an old or invalid container", kubernetesContainerRestartCountLabel)
+func getContainerInfoFromLabel(labels map[string]string) (*labelledContainerInfo, error) {
+	var err error
+	containerInfo := labelledContainerInfo{
+		PodName:      getStringValueFromLabel(labels, kubernetesPodNameLabel),
+		PodNamespace: getStringValueFromLabel(labels, kubernetesPodNamespaceLabel),
+		PodUID:       types.UID(getStringValueFromLabel(labels, kubernetesPodUIDLabel)),
+		Name:         getStringValueFromLabel(labels, kubernetesContainerNameLabel),
+		Hash:         getStringValueFromLabel(labels, kubernetesContainerHashLabel),
+		TerminationMessagePath: getStringValueFromLabel(labels, kubernetesContainerTerminationMessagePathLabel),
 	}
-	return restartCount, err
+	containerInfo.RestartCount, err = getIntValueFromLabel(labels, kubernetesContainerRestartCountLabel)
+	return &containerInfo, err
 }
 
-func getTerminationMessagePathFromLabel(labels map[string]string) string {
-	if terminationMessagePath, found := labels[kubernetesContainerTerminationMessagePath]; found {
-		return terminationMessagePath
-	} else {
-		// Do not report error, because there should be many old containers without this label now.
-		// Return empty string "" for these containers, the caller will get terminationMessagePath by other ways.
-		glog.V(3).Infof("Container doesn't have label %s, it may be an old or invalid container", kubernetesContainerTerminationMessagePath)
-		return ""
+func getStringValueFromLabel(labels map[string]string, label string) string {
+	if value, found := labels[label]; found {
+		return value
+	}
+	// Do not report error, because there should be many old containers without label now.
+	glog.V(3).Infof("Container doesn't have label %s, it may be an old or invalid container", label)
+	// Return empty string "" for these containers, the caller will get value by other ways.
+	return ""
+}
+
+func getIntValueFromLabel(labels map[string]string, label string) (int, error) {
+	if strValue, found := labels[label]; found {
+		intValue, err := strconv.Atoi(strValue)
+		if err != nil {
+			// This really should not happen. Just set value to 0 to handle this abnormal case
+			return 0, err
+		}
+		return intValue, nil
 	}
+	// Do not report error, because there should be many old containers without label now.
+	glog.V(3).Infof("Container doesn't have label %s, it may be an old or invalid container", label)
+	// Just set the value to 0
+	return 0, nil
 }

pkg/kubelet/dockertools/labels_test.go

@@ -0,0 +1,59 @@
+/*
+Copyright 2015 The Kubernetes Authors 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 dockertools
+
+import (
+	"reflect"
+	"strconv"
+	"testing"
+
+	"k8s.io/kubernetes/pkg/api"
+	kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
+)
+
+func TestLabels(t *testing.T) {
+	restartCount := 5
+	container := &api.Container{
+		Name: "test_container",
+		TerminationMessagePath: "/tmp",
+	}
+	pod := &api.Pod{
+		ObjectMeta: api.ObjectMeta{
+			Name:      "test_pod",
+			Namespace: "test_pod_namespace",
+			UID:       "test_pod_uid",
+		},
+	}
+	expected := &labelledContainerInfo{
+		PodName:                pod.Name,
+		PodNamespace:           pod.Namespace,
+		PodUID:                 pod.UID,
+		Name:                   container.Name,
+		Hash:                   strconv.FormatUint(kubecontainer.HashContainer(container), 16),
+		RestartCount:           restartCount,
+		TerminationMessagePath: container.TerminationMessagePath,
+	}
+
+	labels := newLabels(container, pod, restartCount)
+	containerInfo, err := getContainerInfoFromLabel(labels)
+	if err != nil {
+		t.Errorf("Unexpected error when getContainerInfoFromLabel: %v", err)
+	}
+	if !reflect.DeepEqual(containerInfo, expected) {
+		t.Errorf("expected %v, got %v", expected, containerInfo)
+	}
+}

pkg/kubelet/dockertools/manager.go

@@ -357,14 +357,14 @@ func (dm *DockerManager) inspectContainer(dockerID, containerName string, pod *a
 
 	glog.V(4).Infof("Container inspect result: %+v", *inspectResult)
 
-	var restartCount int
-	if restartCount, err = getRestartCountFromLabel(inspectResult.Config.Labels); err != nil {
-		glog.Errorf("Get restart count error for container %v: %v", dockerID, err)
+	var containerInfo *labelledContainerInfo
+	if containerInfo, err = getContainerInfoFromLabel(inspectResult.Config.Labels); err != nil {
+		glog.Errorf("Get labelled container info error for container %v: %v", dockerID, err)
 	}
 
 	result.status = api.ContainerStatus{
 		Name:         containerName,
-		RestartCount: restartCount,
+		RestartCount: containerInfo.RestartCount,
 		Image:        inspectResult.Config.Image,
 		ImageID:      DockerPrefix + inspectResult.Image,
 		ContainerID:  DockerPrefix + dockerID,
@@ -408,7 +408,7 @@ func (dm *DockerManager) inspectContainer(dockerID, containerName string, pod *a
 			FinishedAt:  finishedAt,
 			ContainerID: DockerPrefix + dockerID,
 		}
-		terminationMessagePath := getTerminationMessagePathFromLabel(inspectResult.Config.Labels)
+		terminationMessagePath := containerInfo.TerminationMessagePath
 		if terminationMessagePath != "" {
 			path, found := inspectResult.Volumes[terminationMessagePath]
 			if found {

pkg/kubelet/dockertools/manager_test.go

@@ -1360,7 +1360,7 @@ func TestGetRestartCount(t *testing.T) {
 		runSyncPod(t, dm, fakeDocker, pod, nil, false)
 		status, err := dm.GetPodStatus(pod)
 		if err != nil {
-			t.Fatalf("unexpected error %v", err)
+			t.Fatalf("Unexpected error %v", err)
 		}
 		restartCount := status.ContainerStatuses[0].RestartCount
 		if restartCount != expectedCount {
@@ -1372,7 +1372,7 @@ func TestGetRestartCount(t *testing.T) {
 	killOneContainer := func(pod *api.Pod) {
 		status, err := dm.GetPodStatus(pod)
 		if err != nil {
-			t.Fatalf("unexpected error %v", err)
+			t.Fatalf("Unexpected error %v", err)
 		}
 		containerID := kubecontainer.ParseContainerID(status.ContainerStatuses[0].ContainerID)
 		dm.KillContainerInPod(containerID, &pod.Spec.Containers[0], pod, "test container restart count.")
@@ -1438,13 +1438,18 @@ func TestGetTerminationMessagePath(t *testing.T) {
 	containerList := fakeDocker.ContainerList
 	if len(containerList) != 2 {
 		// One for infra container, one for container "bar"
-		t.Fatalf("unexpected container list length %d", len(containerList))
+		t.Fatalf("Unexpected container list length %d", len(containerList))
 	}
 	inspectResult, err := dm.client.InspectContainer(containerList[0].ID)
 	if err != nil {
-		t.Fatalf("unexpected inspect error %v", err)
+		t.Fatalf("Unexpected inspect error: %v", err)
+	}
+	var containerInfo *labelledContainerInfo
+	containerInfo, err = getContainerInfoFromLabel(inspectResult.Config.Labels)
+	if err != nil {
+		t.Fatalf("Unexpected error when getContainerInfoFromLabel: %v", err)
 	}
-	terminationMessagePath := getTerminationMessagePathFromLabel(inspectResult.Config.Labels)
+	terminationMessagePath := containerInfo.TerminationMessagePath
 	if terminationMessagePath != containers[0].TerminationMessagePath {
 		t.Errorf("expected termination message path %s, got %s", containers[0].TerminationMessagePath, terminationMessagePath)
 	}