discovery/kubernetes: add present labels for labels/annotations (#5443)

Signed-off-by: Simon Pasquier <spasquie@redhat.com>

discovery/kubernetes/endpoints_test.go

@@ -390,6 +390,7 @@ func TestEndpointsDiscoveryWithService(t *testing.T) {
 					"__meta_kubernetes_namespace":                "default",
 					"__meta_kubernetes_endpoints_name":           "testendpoints",
 					"__meta_kubernetes_service_label_app":        "test",
+					"__meta_kubernetes_service_labelpresent_app": "true",
 					"__meta_kubernetes_service_name":             "testendpoints",
 				},
 				Source: "endpoints/default/testendpoints",
@@ -455,8 +456,10 @@ func TestEndpointsDiscoveryWithServiceUpdate(t *testing.T) {
 					"__meta_kubernetes_namespace":                      "default",
 					"__meta_kubernetes_endpoints_name":                 "testendpoints",
 					"__meta_kubernetes_service_label_app":              "svc",
+					"__meta_kubernetes_service_labelpresent_app":       "true",
 					"__meta_kubernetes_service_name":                   "testendpoints",
 					"__meta_kubernetes_service_label_component":        "testing",
+					"__meta_kubernetes_service_labelpresent_component": "true",
 				},
 				Source: "endpoints/default/testendpoints",
 			},
@@ -563,6 +566,7 @@ func TestEndpointsDiscoveryNamespaces(t *testing.T) {
 					"__meta_kubernetes_namespace":                "ns1",
 					"__meta_kubernetes_endpoints_name":           "testendpoints",
 					"__meta_kubernetes_service_label_app":        "app1",
+					"__meta_kubernetes_service_labelpresent_app": "true",
 					"__meta_kubernetes_service_name":             "testendpoints",
 				},
 				Source: "endpoints/ns1/testendpoints",

discovery/kubernetes/ingress.go

@@ -133,7 +133,9 @@ func ingressSourceFromNamespaceAndName(namespace, name string) string {
 const (
 	ingressNameLabel               = metaLabelPrefix + "ingress_name"
 	ingressLabelPrefix             = metaLabelPrefix + "ingress_label_"
+	ingressLabelPresentPrefix      = metaLabelPrefix + "ingress_labelpresent_"
 	ingressAnnotationPrefix        = metaLabelPrefix + "ingress_annotation_"
+	ingressAnnotationPresentPrefix = metaLabelPrefix + "ingress_annotationpresent_"
 	ingressSchemeLabel             = metaLabelPrefix + "ingress_scheme"
 	ingressHostLabel               = metaLabelPrefix + "ingress_host"
 	ingressPathLabel               = metaLabelPrefix + "ingress_path"
@@ -145,13 +147,15 @@ func ingressLabels(ingress *v1beta1.Ingress) model.LabelSet {
 	ls[namespaceLabel] = lv(ingress.Namespace)
 
 	for k, v := range ingress.Labels {
-		ln := strutil.SanitizeLabelName(ingressLabelPrefix + k)
+		ln := strutil.SanitizeLabelName(k)
-		ls[model.LabelName(ln)] = lv(v)
+		ls[model.LabelName(ingressLabelPrefix+ln)] = lv(v)
+		ls[model.LabelName(ingressLabelPresentPrefix+ln)] = presentValue
 	}
 
 	for k, v := range ingress.Annotations {
-		ln := strutil.SanitizeLabelName(ingressAnnotationPrefix + k)
+		ln := strutil.SanitizeLabelName(k)
-		ls[model.LabelName(ln)] = lv(v)
+		ls[model.LabelName(ingressAnnotationPrefix+ln)] = lv(v)
+		ls[model.LabelName(ingressAnnotationPresentPrefix+ln)] = presentValue
 	}
 	return ls
 }

discovery/kubernetes/ingress_test.go

@@ -121,7 +121,9 @@ func expectedTargetGroups(ns string, tls TLSMode) map[string]*targetgroup.Group
 				"__meta_kubernetes_ingress_name":                             "testingress",
 				"__meta_kubernetes_namespace":                                lv(ns),
 				"__meta_kubernetes_ingress_label_testlabel":                  "testvalue",
+				"__meta_kubernetes_ingress_labelpresent_testlabel":           "true",
 				"__meta_kubernetes_ingress_annotation_testannotation":        "testannotationvalue",
+				"__meta_kubernetes_ingress_annotationpresent_testannotation": "true",
 			},
 			Source: key,
 		},

discovery/kubernetes/kubernetes.go

@@ -43,6 +43,7 @@ const (
 	metaLabelPrefix  = model.MetaLabelPrefix + "kubernetes_"
 	namespaceLabel   = metaLabelPrefix + "namespace"
 	metricsNamespace = "prometheus_sd_kubernetes"
+	presentValue     = model.LabelValue("true")
 )
 
 var (

discovery/kubernetes/kubernetes_test.go

@@ -54,6 +54,7 @@ type k8sDiscoveryTest struct {
 }
 
 func (d k8sDiscoveryTest) Run(t *testing.T) {
+	t.Helper()
 	ch := make(chan []*targetgroup.Group)
 	ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
 	defer cancel()
@@ -124,6 +125,7 @@ Loop:
 }
 
 func requireTargetGroups(t *testing.T, expected, res map[string]*targetgroup.Group) {
+	t.Helper()
 	b1, err := json.Marshal(expected)
 	if err != nil {
 		panic(err)

discovery/kubernetes/node.go

@@ -142,7 +142,9 @@ func nodeSourceFromName(name string) string {
 const (
 	nodeNameLabel               = metaLabelPrefix + "node_name"
 	nodeLabelPrefix             = metaLabelPrefix + "node_label_"
+	nodeLabelPresentPrefix      = metaLabelPrefix + "node_labelpresent_"
 	nodeAnnotationPrefix        = metaLabelPrefix + "node_annotation_"
+	nodeAnnotationPresentPrefix = metaLabelPrefix + "node_annotationpresent_"
 	nodeAddressPrefix           = metaLabelPrefix + "node_address_"
 )
 
@@ -152,13 +154,15 @@ func nodeLabels(n *apiv1.Node) model.LabelSet {
 	ls[nodeNameLabel] = lv(n.Name)
 
 	for k, v := range n.Labels {
-		ln := strutil.SanitizeLabelName(nodeLabelPrefix + k)
+		ln := strutil.SanitizeLabelName(k)
-		ls[model.LabelName(ln)] = lv(v)
+		ls[model.LabelName(nodeLabelPrefix+ln)] = lv(v)
+		ls[model.LabelName(nodeLabelPresentPrefix+ln)] = presentValue
 	}
 
 	for k, v := range n.Annotations {
-		ln := strutil.SanitizeLabelName(nodeAnnotationPrefix + k)
+		ln := strutil.SanitizeLabelName(k)
-		ls[model.LabelName(ln)] = lv(v)
+		ls[model.LabelName(nodeAnnotationPrefix+ln)] = lv(v)
+		ls[model.LabelName(nodeAnnotationPresentPrefix+ln)] = presentValue
 	}
 	return ls
 }

discovery/kubernetes/node_test.go

@@ -77,7 +77,9 @@ func TestNodeDiscoveryBeforeStart(t *testing.T) {
 				Labels: model.LabelSet{
 					"__meta_kubernetes_node_name":                             "test",
 					"__meta_kubernetes_node_label_testlabel":                  "testvalue",
+					"__meta_kubernetes_node_labelpresent_testlabel":           "true",
 					"__meta_kubernetes_node_annotation_testannotation":        "testannotationvalue",
+					"__meta_kubernetes_node_annotationpresent_testannotation": "true",
 				},
 				Source: "node/test",
 			},
@@ -159,6 +161,7 @@ func TestNodeDiscoveryUpdate(t *testing.T) {
 				},
 				Labels: model.LabelSet{
 					"__meta_kubernetes_node_label_Unschedulable":        "true",
+					"__meta_kubernetes_node_labelpresent_Unschedulable": "true",
 					"__meta_kubernetes_node_name":                       "test0",
 				},
 				Source: "node/test0",

discovery/kubernetes/pod.go

@@ -144,7 +144,9 @@ const (
 	podReadyLabel                 = metaLabelPrefix + "pod_ready"
 	podPhaseLabel                 = metaLabelPrefix + "pod_phase"
 	podLabelPrefix                = metaLabelPrefix + "pod_label_"
+	podLabelPresentPrefix         = metaLabelPrefix + "pod_labelpresent_"
 	podAnnotationPrefix           = metaLabelPrefix + "pod_annotation_"
+	podAnnotationPresentPrefix    = metaLabelPrefix + "pod_annotationpresent_"
 	podNodeNameLabel              = metaLabelPrefix + "pod_node_name"
 	podHostIPLabel                = metaLabelPrefix + "pod_host_ip"
 	podUID                        = metaLabelPrefix + "pod_uid"
@@ -185,13 +187,15 @@ func podLabels(pod *apiv1.Pod) model.LabelSet {
 	}
 
 	for k, v := range pod.Labels {
-		ln := strutil.SanitizeLabelName(podLabelPrefix + k)
+		ln := strutil.SanitizeLabelName(k)
-		ls[model.LabelName(ln)] = lv(v)
+		ls[model.LabelName(podLabelPrefix+k)] = lv(v)
+		ls[model.LabelName(podLabelPresentPrefix+ln)] = presentValue
 	}
 
 	for k, v := range pod.Annotations {
-		ln := strutil.SanitizeLabelName(podAnnotationPrefix + k)
+		ln := strutil.SanitizeLabelName(k)
-		ls[model.LabelName(ln)] = lv(v)
+		ls[model.LabelName(podAnnotationPrefix+ln)] = lv(v)
+		ls[model.LabelName(podAnnotationPresentPrefix+ln)] = presentValue
 	}
 
 	return ls

discovery/kubernetes/pod_test.go

@@ -181,7 +181,9 @@ func TestPodDiscoveryBeforeRun(t *testing.T) {
 					"__meta_kubernetes_pod_name":                             "testpod",
 					"__meta_kubernetes_namespace":                            "default",
 					"__meta_kubernetes_pod_label_testlabel":                  "testvalue",
+					"__meta_kubernetes_pod_labelpresent_testlabel":           "true",
 					"__meta_kubernetes_pod_annotation_testannotation":        "testannotationvalue",
+					"__meta_kubernetes_pod_annotationpresent_testannotation": "true",
 					"__meta_kubernetes_pod_node_name":                        "testnode",
 					"__meta_kubernetes_pod_ip":                               "1.2.3.4",
 					"__meta_kubernetes_pod_host_ip":                          "2.3.4.5",

discovery/kubernetes/service.go

@@ -137,7 +137,9 @@ func serviceSourceFromNamespaceAndName(namespace, name string) string {
 const (
 	serviceNameLabel               = metaLabelPrefix + "service_name"
 	serviceLabelPrefix             = metaLabelPrefix + "service_label_"
+	serviceLabelPresentPrefix      = metaLabelPrefix + "service_labelpresent_"
 	serviceAnnotationPrefix        = metaLabelPrefix + "service_annotation_"
+	serviceAnnotationPresentPrefix = metaLabelPrefix + "service_annotationpresent_"
 	servicePortNameLabel           = metaLabelPrefix + "service_port_name"
 	servicePortProtocolLabel       = metaLabelPrefix + "service_port_protocol"
 	serviceClusterIPLabel          = metaLabelPrefix + "service_cluster_ip"
@@ -151,13 +153,15 @@ func serviceLabels(svc *apiv1.Service) model.LabelSet {
 	ls[namespaceLabel] = lv(svc.Namespace)
 
 	for k, v := range svc.Labels {
-		ln := strutil.SanitizeLabelName(serviceLabelPrefix + k)
+		ln := strutil.SanitizeLabelName(k)
-		ls[model.LabelName(ln)] = lv(v)
+		ls[model.LabelName(serviceLabelPrefix+ln)] = lv(v)
+		ls[model.LabelName(serviceLabelPresentPrefix+ln)] = presentValue
 	}
 
 	for k, v := range svc.Annotations {
-		ln := strutil.SanitizeLabelName(serviceAnnotationPrefix + k)
+		ln := strutil.SanitizeLabelName(k)
-		ls[model.LabelName(ln)] = lv(v)
+		ls[model.LabelName(serviceAnnotationPrefix+ln)] = lv(v)
+		ls[model.LabelName(serviceAnnotationPresentPrefix+ln)] = presentValue
 	}
 	return ls
 }

discovery/kubernetes/service_test.go

@@ -189,7 +189,9 @@ func TestServiceDiscoveryUpdate(t *testing.T) {
 					"__meta_kubernetes_service_name":                             "testservice",
 					"__meta_kubernetes_namespace":                                "default",
 					"__meta_kubernetes_service_label_testlabel":                  "testvalue",
+					"__meta_kubernetes_service_labelpresent_testlabel":           "true",
 					"__meta_kubernetes_service_annotation_testannotation":        "testannotationvalue",
+					"__meta_kubernetes_service_annotationpresent_testannotation": "true",
 				},
 				Source: "svc/default/testservice",
 			},

docs/configuration/configuration.md

@@ -708,7 +708,9 @@ Available meta labels:
 
 * `__meta_kubernetes_node_name`: The name of the node object.
 * `__meta_kubernetes_node_label_<labelname>`: Each label from the node object.
+* `__meta_kubernetes_node_labelpresent_<labelname>`: `true` for each label from the node object.
 * `__meta_kubernetes_node_annotation_<annotationname>`: Each annotation from the node object.
+* `__meta_kubernetes_node_annotationpresent_<annotationname>`: `true` for each annotation from the node object.
 * `__meta_kubernetes_node_address_<address_type>`: The first address for each node address type, if it exists.
 
 In addition, the `instance` label for the node will be set to the node name
@@ -724,10 +726,12 @@ service port.
 Available meta labels:
 
 * `__meta_kubernetes_namespace`: The namespace of the service object.
-* `__meta_kubernetes_service_annotation_<annotationname>`: The annotation of the service object.
+* `__meta_kubernetes_service_annotation_<annotationname>`: Each annotation from the service object.
+* `__meta_kubernetes_service_annotationpresent_<annotationname>`: "true" for each annotation of the service object.
 * `__meta_kubernetes_service_cluster_ip`: The cluster IP address of the service. (Does not apply to services of type ExternalName)
 * `__meta_kubernetes_service_external_name`: The DNS name of the service. (Applies to services of type ExternalName)
-* `__meta_kubernetes_service_label_<labelname>`: The label of the service object.
+* `__meta_kubernetes_service_label_<labelname>`: Each label from the service object.
+* `__meta_kubernetes_service_labelpresent_<labelname>`: `true` for each label of the service object.
 * `__meta_kubernetes_service_name`: The name of the service object.
 * `__meta_kubernetes_service_port_name`: Name of the service port for the target.
 * `__meta_kubernetes_service_port_number`: Number of the service port for the target.
@@ -744,8 +748,10 @@ Available meta labels:
 * `__meta_kubernetes_namespace`: The namespace of the pod object.
 * `__meta_kubernetes_pod_name`: The name of the pod object.
 * `__meta_kubernetes_pod_ip`: The pod IP of the pod object.
-* `__meta_kubernetes_pod_label_<labelname>`: The label of the pod object.
+* `__meta_kubernetes_pod_label_<labelname>`: Each label from the pod object.
-* `__meta_kubernetes_pod_annotation_<annotationname>`: The annotation of the pod object.
+* `__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_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.
@@ -789,8 +795,10 @@ Available meta labels:
 
 * `__meta_kubernetes_namespace`: The namespace of the ingress object.
 * `__meta_kubernetes_ingress_name`: The name of the ingress object.
-* `__meta_kubernetes_ingress_label_<labelname>`: The label of the ingress object.
+* `__meta_kubernetes_ingress_label_<labelname>`: Each label from the ingress object.
-* `__meta_kubernetes_ingress_annotation_<annotationname>`: The annotation of the ingress object.
+* `__meta_kubernetes_ingress_labelpresent_<labelname>`: `true` for each label from the ingress object.
+* `__meta_kubernetes_ingress_annotation_<annotationname>`: Each annotation from the ingress object.
+* `__meta_kubernetes_ingress_annotationpresent_<annotationname>`: `true` for each annotation from the ingress object.
 * `__meta_kubernetes_ingress_scheme`: Protocol scheme of ingress, `https` if TLS
   config is set. Defaults to `http`.
 * `__meta_kubernetes_ingress_path`: Path from ingress spec. Defaults to `/`.