Merge pull request #5598 from sh0rez/master

include InitContainers in Kubernetes Service Discovery

discovery/kubernetes/pod.go

@@ -141,6 +141,7 @@ const (
 	podContainerPortNameLabel     = metaLabelPrefix + "pod_container_port_name"
 	podContainerPortNumberLabel   = metaLabelPrefix + "pod_container_port_number"
 	podContainerPortProtocolLabel = metaLabelPrefix + "pod_container_port_protocol"
+	podContainerIsInit            = metaLabelPrefix + "pod_container_init"
 	podReadyLabel                 = metaLabelPrefix + "pod_ready"
 	podPhaseLabel                 = metaLabelPrefix + "pod_phase"
 	podLabelPrefix                = metaLabelPrefix + "pod_label_"
@@ -213,7 +214,10 @@ func (p *Pod) buildPod(pod *apiv1.Pod) *targetgroup.Group {
 	tg.Labels = podLabels(pod)
 	tg.Labels[namespaceLabel] = lv(pod.Namespace)
 
-	for _, c := range pod.Spec.Containers {
+	containers := append(pod.Spec.Containers, pod.Spec.InitContainers...)
+	for i, c := range containers {
+		isInit := i >= len(pod.Spec.Containers)
+
 		// If no ports are defined for the container, create an anonymous
 		// target per container.
 		if len(c.Ports) == 0 {
@@ -222,6 +226,7 @@ func (p *Pod) buildPod(pod *apiv1.Pod) *targetgroup.Group {
 			tg.Targets = append(tg.Targets, model.LabelSet{
 				model.AddressLabel:    lv(pod.Status.PodIP),
 				podContainerNameLabel: lv(c.Name),
+				podContainerIsInit:    lv(strconv.FormatBool(isInit)),
 			})
 			continue
 		}
@@ -236,6 +241,7 @@ func (p *Pod) buildPod(pod *apiv1.Pod) *targetgroup.Group {
 				podContainerPortNumberLabel:   lv(ports),
 				podContainerPortNameLabel:     lv(port.Name),
 				podContainerPortProtocolLabel: lv(string(port.Protocol)),
+				podContainerIsInit:            lv(strconv.FormatBool(isInit)),
 			})
 		}
 	}

discovery/kubernetes/pod_test.go

@@ -117,6 +117,48 @@ func makePods() *v1.Pod {
 	}
 }
 
+func makeInitContainerPods() *v1.Pod {
+	return &v1.Pod{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "testpod",
+			Namespace: "default",
+			UID:       types.UID("abc123"),
+		},
+		Spec: v1.PodSpec{
+			NodeName: "testnode",
+			Containers: []v1.Container{
+				{
+					Name: "testcontainer",
+					Ports: []v1.ContainerPort{
+						{
+							Name:          "testport",
+							Protocol:      v1.ProtocolTCP,
+							ContainerPort: int32(9000),
+						},
+					},
+				},
+			},
+
+			InitContainers: []v1.Container{
+				{
+					Name: "initcontainer",
+				},
+			},
+		},
+		Status: v1.PodStatus{
+			PodIP:  "1.2.3.4",
+			HostIP: "2.3.4.5",
+			Phase:  "Pending",
+			Conditions: []v1.PodCondition{
+				{
+					Type:   v1.PodReady,
+					Status: v1.ConditionFalse,
+				},
+			},
+		},
+	}
+}
+
 func expectedPodTargetGroups(ns string) map[string]*targetgroup.Group {
 	key := fmt.Sprintf("pod/%s/testpod", ns)
 	return map[string]*targetgroup.Group{
@@ -128,6 +170,7 @@ func expectedPodTargetGroups(ns string) map[string]*targetgroup.Group {
 					"__meta_kubernetes_pod_container_port_name":     "testport",
 					"__meta_kubernetes_pod_container_port_number":   "9000",
 					"__meta_kubernetes_pod_container_port_protocol": "TCP",
+					"__meta_kubernetes_pod_container_init":          "false",
 				},
 			},
 			Labels: model.LabelSet{
@@ -164,6 +207,7 @@ func TestPodDiscoveryBeforeRun(t *testing.T) {
 						"__meta_kubernetes_pod_container_port_name":     "testport0",
 						"__meta_kubernetes_pod_container_port_number":   "9000",
 						"__meta_kubernetes_pod_container_port_protocol": "TCP",
+						"__meta_kubernetes_pod_container_init":          "false",
 					},
 					{
 						"__address__":                                   "1.2.3.4:9001",
@@ -171,10 +215,12 @@ func TestPodDiscoveryBeforeRun(t *testing.T) {
 						"__meta_kubernetes_pod_container_port_name":     "testport1",
 						"__meta_kubernetes_pod_container_port_number":   "9001",
 						"__meta_kubernetes_pod_container_port_protocol": "UDP",
+						"__meta_kubernetes_pod_container_init":          "false",
 					},
 					{
 						"__address__":                          "1.2.3.4",
 						"__meta_kubernetes_pod_container_name": "testcontainer1",
+						"__meta_kubernetes_pod_container_init": "false",
 					},
 				},
 				Labels: model.LabelSet{
@@ -199,6 +245,31 @@ func TestPodDiscoveryBeforeRun(t *testing.T) {
 	}.Run(t)
 }
 
+func TestPodDiscoveryInitContainer(t *testing.T) {
+	n, c := makeDiscovery(RolePod, NamespaceDiscovery{})
+
+	ns := "default"
+	key := fmt.Sprintf("pod/%s/testpod", ns)
+	expected := expectedPodTargetGroups(ns)
+	expected[key].Targets = append(expected[key].Targets, model.LabelSet{
+		"__address__":                          "1.2.3.4",
+		"__meta_kubernetes_pod_container_name": "initcontainer",
+		"__meta_kubernetes_pod_container_init": "true",
+	})
+	expected[key].Labels["__meta_kubernetes_pod_phase"] = "Pending"
+	expected[key].Labels["__meta_kubernetes_pod_ready"] = "false"
+
+	k8sDiscoveryTest{
+		discovery: n,
+		beforeRun: func() {
+			obj := makeInitContainerPods()
+			c.CoreV1().Pods(obj.Namespace).Create(obj)
+		},
+		expectedMaxItems: 1,
+		expectedRes:      expected,
+	}.Run(t)
+}
+
 func TestPodDiscoveryAdd(t *testing.T) {
 	n, c := makeDiscovery(RolePod, NamespaceDiscovery{})
 

docs/configuration/configuration.md

@@ -753,6 +753,7 @@ Available meta labels:
 * `__meta_kubernetes_pod_labelpresent_<labelname>`: `true`for each label from the pod object.
 * `__meta_kubernetes_pod_annotation_<annotationname>`: Each annotation from the pod object.
 * `__meta_kubernetes_pod_annotationpresent_<annotationname>`: `true` for each annotation from the pod object.
+* `__meta_kubernetes_pod_container_init`: `true` if the container is an [InitContainer](https://kubernetes.io/docs/concepts/workloads/pods/init-containers/)
 * `__meta_kubernetes_pod_container_name`: Name of the container the target address points to.
 * `__meta_kubernetes_pod_container_port_name`: Name of the container port.
 * `__meta_kubernetes_pod_container_port_number`: Number of the container port.