kubernetes_sd: Allow attaching node labels for endpoint role

The Kubernetes service discovery can only add node labels to
targets from the pod role.

This commit extends this functionality to the endpoints and
endpointslices roles.

Signed-off-by: Filip Petkovski <filip.petkovsky@gmail.com>

discovery/kubernetes/endpoints.go

@@ -41,9 +41,11 @@ var (
 type Endpoints struct {
 	logger log.Logger
 
-	endpointsInf cache.SharedInformer
+	endpointsInf     cache.SharedIndexInformer
-	serviceInf   cache.SharedInformer
+	serviceInf       cache.SharedInformer
-	podInf       cache.SharedInformer
+	podInf           cache.SharedInformer
+	nodeInf          cache.SharedInformer
+	withNodeMetadata bool
 
 	podStore       cache.Store
 	endpointsStore cache.Store
@@ -53,19 +55,21 @@ type Endpoints struct {
 }
 
 // NewEndpoints returns a new endpoints discovery.
-func NewEndpoints(l log.Logger, svc, eps, pod cache.SharedInformer) *Endpoints {
+func NewEndpoints(l log.Logger, eps cache.SharedIndexInformer, svc, pod, node cache.SharedInformer) *Endpoints {
 	if l == nil {
 		l = log.NewNopLogger()
 	}
 	e := &Endpoints{
-		logger:         l,
+		logger:           l,
-		endpointsInf:   eps,
+		endpointsInf:     eps,
-		endpointsStore: eps.GetStore(),
+		endpointsStore:   eps.GetStore(),
-		serviceInf:     svc,
+		serviceInf:       svc,
-		serviceStore:   svc.GetStore(),
+		serviceStore:     svc.GetStore(),
-		podInf:         pod,
+		podInf:           pod,
-		podStore:       pod.GetStore(),
+		podStore:         pod.GetStore(),
-		queue:          workqueue.NewNamed("endpoints"),
+		nodeInf:          node,
+		withNodeMetadata: node != nil,
+		queue:            workqueue.NewNamed("endpoints"),
 	}
 
 	e.endpointsInf.AddEventHandler(cache.ResourceEventHandlerFuncs{
@@ -118,10 +122,38 @@ func NewEndpoints(l log.Logger, svc, eps, pod cache.SharedInformer) *Endpoints {
 			serviceUpdate(o)
 		},
 	})
+	if e.withNodeMetadata {
+		e.nodeInf.AddEventHandler(cache.ResourceEventHandlerFuncs{
+			AddFunc: func(o interface{}) {
+				node := o.(*apiv1.Node)
+				e.enqueueNode(node.Name)
+			},
+			UpdateFunc: func(_, o interface{}) {
+				node := o.(*apiv1.Node)
+				e.enqueueNode(node.Name)
+			},
+			DeleteFunc: func(o interface{}) {
+				node := o.(*apiv1.Node)
+				e.enqueueNode(node.Name)
+			},
+		})
+	}
 
 	return e
 }
 
+func (e *Endpoints) enqueueNode(nodeName string) {
+	endpoints, err := e.endpointsInf.GetIndexer().ByIndex(nodeIndex, nodeName)
+	if err != nil {
+		level.Error(e.logger).Log("msg", "Error getting endpoints for node", "node", nodeName, "err", err)
+		return
+	}
+
+	for _, endpoint := range endpoints {
+		e.enqueue(endpoint)
+	}
+}
+
 func (e *Endpoints) enqueue(obj interface{}) {
 	key, err := cache.DeletionHandlingMetaNamespaceKeyFunc(obj)
 	if err != nil {
@@ -135,7 +167,12 @@ func (e *Endpoints) enqueue(obj interface{}) {
 func (e *Endpoints) Run(ctx context.Context, ch chan<- []*targetgroup.Group) {
 	defer e.queue.ShutDown()
 
-	if !cache.WaitForCacheSync(ctx.Done(), e.endpointsInf.HasSynced, e.serviceInf.HasSynced, e.podInf.HasSynced) {
+	cacheSyncs := []cache.InformerSynced{e.endpointsInf.HasSynced, e.serviceInf.HasSynced, e.podInf.HasSynced}
+	if e.withNodeMetadata {
+		cacheSyncs = append(cacheSyncs, e.nodeInf.HasSynced)
+	}
+
+	if !cache.WaitForCacheSync(ctx.Done(), cacheSyncs...) {
 		if !errors.Is(ctx.Err(), context.Canceled) {
 			level.Error(e.logger).Log("msg", "endpoints informer unable to sync cache")
 		}
@@ -257,6 +294,10 @@ func (e *Endpoints) buildEndpoints(eps *apiv1.Endpoints) *targetgroup.Group {
 			target[model.LabelName(endpointHostname)] = lv(addr.Hostname)
 		}
 
+		if e.withNodeMetadata {
+			target = addNodeLabels(target, e.nodeInf, e.logger, addr.NodeName)
+		}
+
 		pod := e.resolvePodRef(addr.TargetRef)
 		if pod == nil {
 			// This target is not a Pod, so don't continue with Pod specific logic.
@@ -387,3 +428,31 @@ func (e *Endpoints) addServiceLabels(ns, name string, tg *targetgroup.Group) {
 
 	tg.Labels = tg.Labels.Merge(serviceLabels(svc))
 }
+
+func addNodeLabels(tg model.LabelSet, nodeInf cache.SharedInformer, logger log.Logger, nodeName *string) model.LabelSet {
+	if nodeName == nil {
+		return tg
+	}
+
+	obj, exists, err := nodeInf.GetStore().GetByKey(*nodeName)
+	if err != nil {
+		level.Error(logger).Log("msg", "Error getting node", "node", *nodeName, "err", err)
+		return tg
+	}
+
+	if !exists {
+		return tg
+	}
+
+	node := obj.(*apiv1.Node)
+	// Allocate one target label for the node name,
+	// and two target labels for each node label.
+	nodeLabelset := make(model.LabelSet, 1+2*len(node.GetLabels()))
+	nodeLabelset[nodeNameLabel] = lv(*nodeName)
+	for k, v := range node.GetLabels() {
+		ln := strutil.SanitizeLabelName(k)
+		nodeLabelset[model.LabelName(nodeLabelPrefix+ln)] = lv(v)
+		nodeLabelset[model.LabelName(nodeLabelPresentPrefix+ln)] = presentValue
+	}
+	return tg.Merge(nodeLabelset)
+}

discovery/kubernetes/endpoints_test.go

@@ -478,6 +478,126 @@ func TestEndpointsDiscoveryWithServiceUpdate(t *testing.T) {
 	}.Run(t)
 }
 
+func TestEndpointsDiscoveryWithNodeMetadata(t *testing.T) {
+	metadataConfig := AttachMetadataConfig{Node: true}
+	nodeLabels := map[string]string{"az": "us-east1"}
+	node := makeNode("foobar", "", "", nodeLabels, nil)
+	svc := &v1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "testendpoints",
+			Namespace: "default",
+			Labels: map[string]string{
+				"app/name": "test",
+			},
+		},
+	}
+	n, _ := makeDiscoveryWithMetadata(RoleEndpoint, NamespaceDiscovery{}, metadataConfig, makeEndpoints(), svc, node)
+
+	k8sDiscoveryTest{
+		discovery:        n,
+		expectedMaxItems: 1,
+		expectedRes: map[string]*targetgroup.Group{
+			"endpoints/default/testendpoints": {
+				Targets: []model.LabelSet{
+					{
+						"__address__":                              "1.2.3.4:9000",
+						"__meta_kubernetes_endpoint_hostname":      "testendpoint1",
+						"__meta_kubernetes_endpoint_node_name":     "foobar",
+						"__meta_kubernetes_endpoint_port_name":     "testport",
+						"__meta_kubernetes_endpoint_port_protocol": "TCP",
+						"__meta_kubernetes_endpoint_ready":         "true",
+						"__meta_kubernetes_node_label_az":          "us-east1",
+						"__meta_kubernetes_node_labelpresent_az":   "true",
+						"__meta_kubernetes_node_name":              "foobar",
+					},
+					{
+						"__address__":                              "2.3.4.5:9001",
+						"__meta_kubernetes_endpoint_port_name":     "testport",
+						"__meta_kubernetes_endpoint_port_protocol": "TCP",
+						"__meta_kubernetes_endpoint_ready":         "true",
+					},
+					{
+						"__address__":                              "2.3.4.5:9001",
+						"__meta_kubernetes_endpoint_port_name":     "testport",
+						"__meta_kubernetes_endpoint_port_protocol": "TCP",
+						"__meta_kubernetes_endpoint_ready":         "false",
+					},
+				},
+				Labels: model.LabelSet{
+					"__meta_kubernetes_namespace":                     "default",
+					"__meta_kubernetes_endpoints_name":                "testendpoints",
+					"__meta_kubernetes_service_label_app_name":        "test",
+					"__meta_kubernetes_service_labelpresent_app_name": "true",
+					"__meta_kubernetes_service_name":                  "testendpoints",
+				},
+				Source: "endpoints/default/testendpoints",
+			},
+		},
+	}.Run(t)
+}
+
+func TestEndpointsDiscoveryWithUpdatedNodeMetadata(t *testing.T) {
+	nodeLabels := map[string]string{"az": "us-east1"}
+	nodes := makeNode("foobar", "", "", nodeLabels, nil)
+	metadataConfig := AttachMetadataConfig{Node: true}
+	svc := &v1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "testendpoints",
+			Namespace: "default",
+			Labels: map[string]string{
+				"app/name": "test",
+			},
+		},
+	}
+	n, c := makeDiscoveryWithMetadata(RoleEndpoint, NamespaceDiscovery{}, metadataConfig, makeEndpoints(), nodes, svc)
+
+	k8sDiscoveryTest{
+		discovery: n,
+		afterStart: func() {
+			nodes.Labels["az"] = "eu-central1"
+			c.CoreV1().Nodes().Update(context.Background(), nodes, metav1.UpdateOptions{})
+		},
+		expectedMaxItems: 2,
+		expectedRes: map[string]*targetgroup.Group{
+			"endpoints/default/testendpoints": {
+				Targets: []model.LabelSet{
+					{
+						"__address__":                              "1.2.3.4:9000",
+						"__meta_kubernetes_endpoint_hostname":      "testendpoint1",
+						"__meta_kubernetes_endpoint_node_name":     "foobar",
+						"__meta_kubernetes_endpoint_port_name":     "testport",
+						"__meta_kubernetes_endpoint_port_protocol": "TCP",
+						"__meta_kubernetes_endpoint_ready":         "true",
+						"__meta_kubernetes_node_label_az":          "eu-central1",
+						"__meta_kubernetes_node_labelpresent_az":   "true",
+						"__meta_kubernetes_node_name":              "foobar",
+					},
+					{
+						"__address__":                              "2.3.4.5:9001",
+						"__meta_kubernetes_endpoint_port_name":     "testport",
+						"__meta_kubernetes_endpoint_port_protocol": "TCP",
+						"__meta_kubernetes_endpoint_ready":         "true",
+					},
+					{
+						"__address__":                              "2.3.4.5:9001",
+						"__meta_kubernetes_endpoint_port_name":     "testport",
+						"__meta_kubernetes_endpoint_port_protocol": "TCP",
+						"__meta_kubernetes_endpoint_ready":         "false",
+					},
+				},
+				Labels: model.LabelSet{
+					"__meta_kubernetes_namespace":                     "default",
+					"__meta_kubernetes_endpoints_name":                "testendpoints",
+					"__meta_kubernetes_service_label_app_name":        "test",
+					"__meta_kubernetes_service_labelpresent_app_name": "true",
+					"__meta_kubernetes_service_name":                  "testendpoints",
+				},
+				Source: "endpoints/default/testendpoints",
+			},
+		},
+	}.Run(t)
+}
+
 func TestEndpointsDiscoveryNamespaces(t *testing.T) {
 	epOne := makeEndpoints()
 	epOne.Namespace = "ns1"

discovery/kubernetes/endpointslice.go

@@ -42,9 +42,11 @@ var (
 type EndpointSlice struct {
 	logger log.Logger
 
-	endpointSliceInf cache.SharedInformer
+	endpointSliceInf cache.SharedIndexInformer
 	serviceInf       cache.SharedInformer
 	podInf           cache.SharedInformer
+	nodeInf          cache.SharedInformer
+	withNodeMetadata bool
 
 	podStore           cache.Store
 	endpointSliceStore cache.Store
@@ -54,7 +56,7 @@ type EndpointSlice struct {
 }
 
 // NewEndpointSlice returns a new endpointslice discovery.
-func NewEndpointSlice(l log.Logger, svc, eps, pod cache.SharedInformer) *EndpointSlice {
+func NewEndpointSlice(l log.Logger, eps cache.SharedIndexInformer, svc, pod, node cache.SharedInformer) *EndpointSlice {
 	if l == nil {
 		l = log.NewNopLogger()
 	}
@@ -66,6 +68,8 @@ func NewEndpointSlice(l log.Logger, svc, eps, pod cache.SharedInformer) *Endpoin
 		serviceStore:       svc.GetStore(),
 		podInf:             pod,
 		podStore:           pod.GetStore(),
+		nodeInf:            node,
+		withNodeMetadata:   node != nil,
 		queue:              workqueue.NewNamed("endpointSlice"),
 	}
 
@@ -120,9 +124,38 @@ func NewEndpointSlice(l log.Logger, svc, eps, pod cache.SharedInformer) *Endpoin
 		},
 	})
 
+	if e.withNodeMetadata {
+		e.nodeInf.AddEventHandler(cache.ResourceEventHandlerFuncs{
+			AddFunc: func(o interface{}) {
+				node := o.(*apiv1.Node)
+				e.enqueueNode(node.Name)
+			},
+			UpdateFunc: func(_, o interface{}) {
+				node := o.(*apiv1.Node)
+				e.enqueueNode(node.Name)
+			},
+			DeleteFunc: func(o interface{}) {
+				node := o.(*apiv1.Node)
+				e.enqueueNode(node.Name)
+			},
+		})
+	}
+
 	return e
 }
 
+func (e *EndpointSlice) enqueueNode(nodeName string) {
+	endpoints, err := e.endpointSliceInf.GetIndexer().ByIndex(nodeIndex, nodeName)
+	if err != nil {
+		level.Error(e.logger).Log("msg", "Error getting endpoints for node", "node", nodeName, "err", err)
+		return
+	}
+
+	for _, endpoint := range endpoints {
+		e.enqueue(endpoint)
+	}
+}
+
 func (e *EndpointSlice) enqueue(obj interface{}) {
 	key, err := cache.DeletionHandlingMetaNamespaceKeyFunc(obj)
 	if err != nil {
@@ -136,7 +169,11 @@ func (e *EndpointSlice) enqueue(obj interface{}) {
 func (e *EndpointSlice) Run(ctx context.Context, ch chan<- []*targetgroup.Group) {
 	defer e.queue.ShutDown()
 
-	if !cache.WaitForCacheSync(ctx.Done(), e.endpointSliceInf.HasSynced, e.serviceInf.HasSynced, e.podInf.HasSynced) {
+	cacheSyncs := []cache.InformerSynced{e.endpointSliceInf.HasSynced, e.serviceInf.HasSynced, e.podInf.HasSynced}
+	if e.withNodeMetadata {
+		cacheSyncs = append(cacheSyncs, e.nodeInf.HasSynced)
+	}
+	if !cache.WaitForCacheSync(ctx.Done(), cacheSyncs...) {
 		if ctx.Err() != context.Canceled {
 			level.Error(e.logger).Log("msg", "endpointslice informer unable to sync cache")
 		}
@@ -282,6 +319,10 @@ func (e *EndpointSlice) buildEndpointSlice(eps endpointSliceAdaptor) *targetgrou
 			target[model.LabelName(endpointSliceEndpointTopologyLabelPresentPrefix+ln)] = presentValue
 		}
 
+		if e.withNodeMetadata {
+			target = addNodeLabels(target, e.nodeInf, e.logger, ep.nodename())
+		}
+
 		pod := e.resolvePodRef(ep.targetRef())
 		if pod == nil {
 			// This target is not a Pod, so don't continue with Pod specific logic.

discovery/kubernetes/endpointslice_adaptor.go

@@ -41,6 +41,7 @@ type endpointSlicePortAdaptor interface {
 type endpointSliceEndpointAdaptor interface {
 	addresses() []string
 	hostname() *string
+	nodename() *string
 	conditions() endpointSliceEndpointConditionsAdaptor
 	targetRef() *corev1.ObjectReference
 	topology() map[string]string
@@ -164,6 +165,10 @@ func (e *endpointSliceEndpointAdaptorV1) hostname() *string {
 	return e.endpoint.Hostname
 }
 
+func (e *endpointSliceEndpointAdaptorV1) nodename() *string {
+	return e.endpoint.NodeName
+}
+
 func (e *endpointSliceEndpointAdaptorV1) conditions() endpointSliceEndpointConditionsAdaptor {
 	return newEndpointSliceEndpointConditionsAdaptorFromV1(e.endpoint.Conditions)
 }
@@ -204,6 +209,10 @@ func (e *endpointSliceEndpointAdaptorV1beta1) hostname() *string {
 	return e.endpoint.Hostname
 }
 
+func (e *endpointSliceEndpointAdaptorV1beta1) nodename() *string {
+	return e.endpoint.NodeName
+}
+
 func (e *endpointSliceEndpointAdaptorV1beta1) conditions() endpointSliceEndpointConditionsAdaptor {
 	return newEndpointSliceEndpointConditionsAdaptorFromV1beta1(e.endpoint.Conditions)
 }

discovery/kubernetes/endpointslice_test.go

@@ -68,6 +68,7 @@ func makeEndpointSliceV1() *v1.EndpointSlice {
 				Conditions: v1.EndpointConditions{Ready: boolptr(true)},
 				Hostname:   strptr("testendpoint1"),
 				TargetRef:  &corev1.ObjectReference{},
+				NodeName:   strptr("foobar"),
 				DeprecatedTopology: map[string]string{
 					"topology": "value",
 				},
@@ -688,6 +689,147 @@ func TestEndpointSliceDiscoveryWithServiceUpdate(t *testing.T) {
 	}.Run(t)
 }
 
+func TestEndpointsSlicesDiscoveryWithNodeMetadata(t *testing.T) {
+	metadataConfig := AttachMetadataConfig{Node: true}
+	nodeLabels := map[string]string{"az": "us-east1"}
+	svc := &corev1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "testendpoints",
+			Namespace: "default",
+			Labels: map[string]string{
+				"app/name": "test",
+			},
+		},
+	}
+	objs := []runtime.Object{makeEndpointSliceV1(), makeNode("foobar", "", "", nodeLabels, nil), svc}
+	n, _ := makeDiscoveryWithMetadata(RoleEndpointSlice, NamespaceDiscovery{}, metadataConfig, objs...)
+
+	k8sDiscoveryTest{
+		discovery:        n,
+		expectedMaxItems: 1,
+		expectedRes: map[string]*targetgroup.Group{
+			"endpointslice/default/testendpoints": {
+				Targets: []model.LabelSet{
+					{
+						"__address__": "1.2.3.4:9000",
+						"__meta_kubernetes_endpointslice_address_target_kind":                "",
+						"__meta_kubernetes_endpointslice_address_target_name":                "",
+						"__meta_kubernetes_endpointslice_endpoint_conditions_ready":          "true",
+						"__meta_kubernetes_endpointslice_endpoint_hostname":                  "testendpoint1",
+						"__meta_kubernetes_endpointslice_endpoint_topology_present_topology": "true",
+						"__meta_kubernetes_endpointslice_endpoint_topology_topology":         "value",
+						"__meta_kubernetes_endpointslice_port":                               "9000",
+						"__meta_kubernetes_endpointslice_port_app_protocol":                  "http",
+						"__meta_kubernetes_endpointslice_port_name":                          "testport",
+						"__meta_kubernetes_endpointslice_port_protocol":                      "TCP",
+						"__meta_kubernetes_node_label_az":                                    "us-east1",
+						"__meta_kubernetes_node_labelpresent_az":                             "true",
+						"__meta_kubernetes_node_name":                                        "foobar",
+					},
+					{
+						"__address__": "2.3.4.5:9000",
+						"__meta_kubernetes_endpointslice_endpoint_conditions_ready": "true",
+						"__meta_kubernetes_endpointslice_port":                      "9000",
+						"__meta_kubernetes_endpointslice_port_app_protocol":         "http",
+						"__meta_kubernetes_endpointslice_port_name":                 "testport",
+						"__meta_kubernetes_endpointslice_port_protocol":             "TCP",
+					},
+					{
+						"__address__": "3.4.5.6:9000",
+						"__meta_kubernetes_endpointslice_endpoint_conditions_ready": "false",
+						"__meta_kubernetes_endpointslice_port":                      "9000",
+						"__meta_kubernetes_endpointslice_port_app_protocol":         "http",
+						"__meta_kubernetes_endpointslice_port_name":                 "testport",
+						"__meta_kubernetes_endpointslice_port_protocol":             "TCP",
+					},
+				},
+				Labels: model.LabelSet{
+					"__meta_kubernetes_endpointslice_address_type":    "IPv4",
+					"__meta_kubernetes_endpointslice_name":            "testendpoints",
+					"__meta_kubernetes_namespace":                     "default",
+					"__meta_kubernetes_service_label_app_name":        "test",
+					"__meta_kubernetes_service_labelpresent_app_name": "true",
+					"__meta_kubernetes_service_name":                  "testendpoints",
+				},
+				Source: "endpointslice/default/testendpoints",
+			},
+		},
+	}.Run(t)
+}
+
+func TestEndpointsSlicesDiscoveryWithUpdatedNodeMetadata(t *testing.T) {
+	metadataConfig := AttachMetadataConfig{Node: true}
+	nodeLabels := map[string]string{"az": "us-east1"}
+	svc := &corev1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "testendpoints",
+			Namespace: "default",
+			Labels: map[string]string{
+				"app/name": "test",
+			},
+		},
+	}
+	node := makeNode("foobar", "", "", nodeLabels, nil)
+	objs := []runtime.Object{makeEndpointSliceV1(), node, svc}
+	n, c := makeDiscoveryWithMetadata(RoleEndpointSlice, NamespaceDiscovery{}, metadataConfig, objs...)
+
+	k8sDiscoveryTest{
+		discovery:        n,
+		expectedMaxItems: 2,
+		afterStart: func() {
+			node.Labels["az"] = "us-central1"
+			c.CoreV1().Nodes().Update(context.Background(), node, metav1.UpdateOptions{})
+		},
+		expectedRes: map[string]*targetgroup.Group{
+			"endpointslice/default/testendpoints": {
+				Targets: []model.LabelSet{
+					{
+						"__address__": "1.2.3.4:9000",
+						"__meta_kubernetes_endpointslice_address_target_kind":                "",
+						"__meta_kubernetes_endpointslice_address_target_name":                "",
+						"__meta_kubernetes_endpointslice_endpoint_conditions_ready":          "true",
+						"__meta_kubernetes_endpointslice_endpoint_hostname":                  "testendpoint1",
+						"__meta_kubernetes_endpointslice_endpoint_topology_present_topology": "true",
+						"__meta_kubernetes_endpointslice_endpoint_topology_topology":         "value",
+						"__meta_kubernetes_endpointslice_port":                               "9000",
+						"__meta_kubernetes_endpointslice_port_app_protocol":                  "http",
+						"__meta_kubernetes_endpointslice_port_name":                          "testport",
+						"__meta_kubernetes_endpointslice_port_protocol":                      "TCP",
+						"__meta_kubernetes_node_label_az":                                    "us-central1",
+						"__meta_kubernetes_node_labelpresent_az":                             "true",
+						"__meta_kubernetes_node_name":                                        "foobar",
+					},
+					{
+						"__address__": "2.3.4.5:9000",
+						"__meta_kubernetes_endpointslice_endpoint_conditions_ready": "true",
+						"__meta_kubernetes_endpointslice_port":                      "9000",
+						"__meta_kubernetes_endpointslice_port_app_protocol":         "http",
+						"__meta_kubernetes_endpointslice_port_name":                 "testport",
+						"__meta_kubernetes_endpointslice_port_protocol":             "TCP",
+					},
+					{
+						"__address__": "3.4.5.6:9000",
+						"__meta_kubernetes_endpointslice_endpoint_conditions_ready": "false",
+						"__meta_kubernetes_endpointslice_port":                      "9000",
+						"__meta_kubernetes_endpointslice_port_app_protocol":         "http",
+						"__meta_kubernetes_endpointslice_port_name":                 "testport",
+						"__meta_kubernetes_endpointslice_port_protocol":             "TCP",
+					},
+				},
+				Labels: model.LabelSet{
+					"__meta_kubernetes_endpointslice_address_type":    "IPv4",
+					"__meta_kubernetes_endpointslice_name":            "testendpoints",
+					"__meta_kubernetes_namespace":                     "default",
+					"__meta_kubernetes_service_label_app_name":        "test",
+					"__meta_kubernetes_service_labelpresent_app_name": "true",
+					"__meta_kubernetes_service_name":                  "testendpoints",
+				},
+				Source: "endpointslice/default/testendpoints",
+			},
+		},
+	}.Run(t)
+}
+
 func TestEndpointSliceDiscoveryNamespaces(t *testing.T) {
 	epOne := makeEndpointSliceV1()
 	epOne.Namespace = "ns1"

discovery/kubernetes/kubernetes.go

@@ -23,6 +23,8 @@ import (
 	"sync"
 	"time"
 
+	disv1beta1 "k8s.io/api/discovery/v1beta1"
+
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
 	"github.com/prometheus/client_golang/prometheus"
@@ -31,7 +33,6 @@ import (
 	"github.com/prometheus/common/version"
 	apiv1 "k8s.io/api/core/v1"
 	disv1 "k8s.io/api/discovery/v1"
-	disv1beta1 "k8s.io/api/discovery/v1beta1"
 	networkv1 "k8s.io/api/networking/v1"
 	"k8s.io/api/networking/v1beta1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -406,7 +407,7 @@ func (d *Discovery) Run(ctx context.Context, ch chan<- []*targetgroup.Group) {
 		}
 
 		for _, namespace := range namespaces {
-			var informer cache.SharedInformer
+			var informer cache.SharedIndexInformer
 			if v1Supported {
 				e := d.client.DiscoveryV1().EndpointSlices(namespace)
 				elw := &cache.ListWatch{
@@ -421,7 +422,7 @@ func (d *Discovery) Run(ctx context.Context, ch chan<- []*targetgroup.Group) {
 						return e.Watch(ctx, options)
 					},
 				}
-				informer = cache.NewSharedInformer(elw, &disv1.EndpointSlice{}, resyncPeriod)
+				informer = d.newEndpointSlicesByNodeInformer(elw, &disv1.EndpointSlice{})
 			} else {
 				e := d.client.DiscoveryV1beta1().EndpointSlices(namespace)
 				elw := &cache.ListWatch{
@@ -436,7 +437,7 @@ func (d *Discovery) Run(ctx context.Context, ch chan<- []*targetgroup.Group) {
 						return e.Watch(ctx, options)
 					},
 				}
-				informer = cache.NewSharedInformer(elw, &disv1beta1.EndpointSlice{}, resyncPeriod)
+				informer = d.newEndpointSlicesByNodeInformer(elw, &disv1beta1.EndpointSlice{})
 			}
 
 			s := d.client.CoreV1().Services(namespace)
@@ -465,11 +466,17 @@ func (d *Discovery) Run(ctx context.Context, ch chan<- []*targetgroup.Group) {
 					return p.Watch(ctx, options)
 				},
 			}
+			var nodeInf cache.SharedInformer
+			if d.attachMetadata.Node {
+				nodeInf = d.newNodeInformer(context.Background())
+				go nodeInf.Run(ctx.Done())
+			}
 			eps := NewEndpointSlice(
 				log.With(d.logger, "role", "endpointslice"),
-				cache.NewSharedInformer(slw, &apiv1.Service{}, resyncPeriod),
 				informer,
+				cache.NewSharedInformer(slw, &apiv1.Service{}, resyncPeriod),
 				cache.NewSharedInformer(plw, &apiv1.Pod{}, resyncPeriod),
+				nodeInf,
 			)
 			d.discoverers = append(d.discoverers, eps)
 			go eps.endpointSliceInf.Run(ctx.Done())
@@ -517,11 +524,18 @@ func (d *Discovery) Run(ctx context.Context, ch chan<- []*targetgroup.Group) {
 					return p.Watch(ctx, options)
 				},
 			}
+			var nodeInf cache.SharedInformer
+			if d.attachMetadata.Node {
+				nodeInf = d.newNodeInformer(ctx)
+				go nodeInf.Run(ctx.Done())
+			}
+
 			eps := NewEndpoints(
 				log.With(d.logger, "role", "endpoint"),
+				d.newEndpointsByNodeInformer(elw),
 				cache.NewSharedInformer(slw, &apiv1.Service{}, resyncPeriod),
-				cache.NewSharedInformer(elw, &apiv1.Endpoints{}, resyncPeriod),
 				cache.NewSharedInformer(plw, &apiv1.Pod{}, resyncPeriod),
+				nodeInf,
 			)
 			d.discoverers = append(d.discoverers, eps)
 			go eps.endpointsInf.Run(ctx.Done())
@@ -735,6 +749,65 @@ func (d *Discovery) newPodsByNodeInformer(plw *cache.ListWatch) cache.SharedInde
 	return cache.NewSharedIndexInformer(plw, &apiv1.Pod{}, resyncPeriod, indexers)
 }
 
+func (d *Discovery) newEndpointsByNodeInformer(plw *cache.ListWatch) cache.SharedIndexInformer {
+	indexers := make(map[string]cache.IndexFunc)
+	if !d.attachMetadata.Node {
+		return cache.NewSharedIndexInformer(plw, &apiv1.Endpoints{}, resyncPeriod, indexers)
+	}
+
+	indexers[nodeIndex] = func(obj interface{}) ([]string, error) {
+		e, ok := obj.(*apiv1.Endpoints)
+		if !ok {
+			return nil, fmt.Errorf("object is not a pod")
+		}
+		var nodes []string
+		for _, target := range e.Subsets {
+			for _, addr := range target.Addresses {
+				if addr.NodeName == nil {
+					continue
+				}
+				nodes = append(nodes, *addr.NodeName)
+			}
+		}
+		return nodes, nil
+	}
+
+	return cache.NewSharedIndexInformer(plw, &apiv1.Endpoints{}, resyncPeriod, indexers)
+}
+
+func (d *Discovery) newEndpointSlicesByNodeInformer(plw *cache.ListWatch, object runtime.Object) cache.SharedIndexInformer {
+	indexers := make(map[string]cache.IndexFunc)
+	if !d.attachMetadata.Node {
+		cache.NewSharedIndexInformer(plw, &disv1.EndpointSlice{}, resyncPeriod, indexers)
+	}
+
+	indexers[nodeIndex] = func(obj interface{}) ([]string, error) {
+		var nodes []string
+		switch e := obj.(type) {
+		case *disv1.EndpointSlice:
+			for _, target := range e.Endpoints {
+				if target.NodeName == nil {
+					continue
+				}
+				nodes = append(nodes, *target.NodeName)
+			}
+		case *disv1beta1.EndpointSlice:
+			for _, target := range e.Endpoints {
+				if target.NodeName == nil {
+					continue
+				}
+				nodes = append(nodes, *target.NodeName)
+			}
+		default:
+			return nil, fmt.Errorf("object is not an endpointslice")
+		}
+
+		return nodes, nil
+	}
+
+	return cache.NewSharedIndexInformer(plw, object, resyncPeriod, indexers)
+}
+
 func checkDiscoveryV1Supported(client kubernetes.Interface) (bool, error) {
 	k8sVer, err := client.Discovery().ServerVersion()
 	if err != nil {

discovery/kubernetes/pod.go

@@ -253,7 +253,7 @@ func (p *Pod) buildPod(pod *apiv1.Pod) *targetgroup.Group {
 	tg.Labels = podLabels(pod)
 	tg.Labels[namespaceLabel] = lv(pod.Namespace)
 	if p.withNodeMetadata {
-		p.attachNodeMetadata(tg, pod)
+		tg.Labels = addNodeLabels(tg.Labels, p.nodeInf, p.logger, &pod.Spec.NodeName)
 	}
 
 	containers := append(pod.Spec.Containers, pod.Spec.InitContainers...)
@@ -291,27 +291,6 @@ func (p *Pod) buildPod(pod *apiv1.Pod) *targetgroup.Group {
 	return tg
 }
 
-func (p *Pod) attachNodeMetadata(tg *targetgroup.Group, pod *apiv1.Pod) {
-	tg.Labels[nodeNameLabel] = lv(pod.Spec.NodeName)
-
-	obj, exists, err := p.nodeInf.GetStore().GetByKey(pod.Spec.NodeName)
-	if err != nil {
-		level.Error(p.logger).Log("msg", "Error getting node", "node", pod.Spec.NodeName, "err", err)
-		return
-	}
-
-	if !exists {
-		return
-	}
-
-	node := obj.(*apiv1.Node)
-	for k, v := range node.GetLabels() {
-		ln := strutil.SanitizeLabelName(k)
-		tg.Labels[model.LabelName(nodeLabelPrefix+ln)] = lv(v)
-		tg.Labels[model.LabelName(nodeLabelPresentPrefix+ln)] = presentValue
-	}
-}
-
 func (p *Pod) enqueuePodsForNode(nodeName string) {
 	pods, err := p.podInf.GetIndexer().ByIndex(nodeIndex, nodeName)
 	if err != nil {

docs/configuration/configuration.md

@@ -1851,7 +1851,7 @@ namespaces:
 
 # Optional metadata to attach to discovered targets. If omitted, no additional metadata is attached.
 attach_metadata:
-# Attaches node metadata to discovered targets. Only valid for role: pod. 
+# Attaches node metadata to discovered targets. Valid for roles: pod, endpoints, endpointslice. 
 # When set to true, Prometheus must have permissions to get Nodes. 
   [ node: <boolean> | default = false ]
 ```