kubernetes: Add discovery of services

retrieval/discovery/kubernetes_v2/endpoint.go

@@ -120,10 +120,6 @@ func endpointsSource(ep apiv1.ObjectMeta) string {
 }
 
 const (
-	serviceNameLabel        = metaLabelPrefix + "service_name"
-	serviceLabelPrefix      = metaLabelPrefix + "service_label_"
-	serviceAnnotationPrefix = metaLabelPrefix + "service_annotation_"
-
 	endpointsNameLabel        = metaLabelPrefix + "endpoints_name"
 	endpointReadyLabel        = metaLabelPrefix + "endpoint_ready"
 	endpointPortNameLabel     = metaLabelPrefix + "endpoint_port_name"
@@ -270,11 +266,5 @@ func (e *Endpoints) addServiceLabels(ns, name string, tg *config.TargetGroup) {
 	}
 	svc = obj.(*apiv1.Service)
 
-	tg.Labels[serviceNameLabel] = lv(svc.Name)
-	for k, v := range svc.Labels {
-		tg.Labels[serviceLabelPrefix+model.LabelName(k)] = lv(v)
-	}
-	for k, v := range svc.Annotations {
-		tg.Labels[serviceAnnotationPrefix+model.LabelName(k)] = lv(v)
-	}
+	tg.Labels = tg.Labels.Merge(serviceLabels(svc))
 }

retrieval/discovery/kubernetes_v2/kubernetes.go

@@ -147,6 +147,20 @@ func (k *Kubernetes) Run(ctx context.Context, ch chan<- []*config.TargetGroup) {
 			time.Sleep(100 * time.Millisecond)
 		}
 		pod.Run(ctx, ch)
+
+	case "service":
+		slw := cache.NewListWatchFromClient(rclient, "services", api.NamespaceAll, nil)
+		svc := NewService(
+			k.logger.With("kubernetes_sd", "service"),
+			cache.NewSharedInformer(slw, &apiv1.Service, resyncPeriod),
+		)
+		go svc.informer.Run(ctx.Done())
+
+		for !svc.informer.HasSynced() {
+			time.Sleep(100 * time.Millisecond)
+		}
+		svc.Run(ctx, ch)
+
 	default:
 		k.logger.Errorf("unknown Kubernetes discovery kind %q", k.role)
 	}

retrieval/discovery/kubernetes_v2/service.go

@@ -0,0 +1,125 @@
+// Copyright 2016 The Prometheus Authors
+// 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 kubernetesv2
+
+import (
+	"net"
+	"strconv"
+
+	"github.com/prometheus/common/log"
+	"github.com/prometheus/common/model"
+	"github.com/prometheus/prometheus/config"
+	"github.com/prometheus/prometheus/util/strutil"
+	"golang.org/x/net/context"
+	apiv1 "k8s.io/client-go/1.5/pkg/api/v1"
+	"k8s.io/client-go/1.5/tools/cache"
+)
+
+// Service implements discovery of Kubernetes services.
+type Service struct {
+	logger   log.Logger
+	informer cache.SharedInformer
+	store    cache.Store
+}
+
+// NewService returns a new service discovery.
+func NewService(l log.Logger, inf cache.SharedInformer) *Service {
+	return &Service{logger: l, informer: inf, store: inf.GetStore()}
+}
+
+// Run implements the TargetProvider interface.
+func (s *Service) Run(ctx context.Context, ch chan<- []*config.TargetGroup) {
+	// Send full initial set of pod targets.
+	var initial []*config.TargetGroup
+	for _, o := range s.store.List() {
+		tg := s.buildService(o.(*apiv1.Service))
+		initial = append(initial, tg)
+	}
+	select {
+	case <-ctx.Done():
+		return
+	case ch <- initial:
+	}
+
+	// Send target groups for service updates.
+	send := func(tg *config.TargetGroup) {
+		select {
+		case <-ctx.Done():
+		case ch <- []*config.TargetGroup{tg}:
+		}
+	}
+	s.informer.AddEventHandler(cache.ResourceEventHandlerFuncs{
+		AddFunc: func(o interface{}) {
+			send(s.buildService(o.(*apiv1.Service)))
+		},
+		DeleteFunc: func(o interface{}) {
+			send(&config.TargetGroup{Source: serviceSource(o.(*apiv1.Service))})
+		},
+		UpdateFunc: func(_, o interface{}) {
+			send(s.buildService(o.(*apiv1.Service)))
+		},
+	})
+
+	// Block until the target provider is explicitly canceled.
+	<-ctx.Done()
+}
+
+func serviceSource(s *apiv1.Service) string {
+	return "svc/" + s.Namespace + "/" + s.Name
+}
+
+const (
+	serviceNameLabel         = metaLabelPrefix + "service_name"
+	serviceLabelPrefix       = metaLabelPrefix + "service_label_"
+	serviceAnnotationPrefix  = metaLabelPrefix + "service_annotation_"
+	servicePortNameLabel     = metaLabelPrefix + "service_port_name"
+	servicePortProtocolLabel = metaLabelPrefix + "service_port_protocol"
+)
+
+func serviceLabels(svc *apiv1.Service) model.LabelSet {
+	ls := make(model.LabelSet, len(svc.Labels)+len(svc.Annotations)+2)
+
+	ls[serviceNameLabel] = lv(svc.Name)
+
+	for k, v := range svc.Labels {
+		ln := strutil.SanitizeLabelName(serviceLabelPrefix + k)
+		ls[model.LabelName(ln)] = lv(v)
+	}
+
+	for k, v := range svc.Annotations {
+		ln := strutil.SanitizeLabelName(serviceAnnotationPrefix + k)
+		ls[model.LabelName(ln)] = lv(v)
+	}
+	return ls
+}
+
+func (s *Service) buildService(svc *apiv1.Service) *config.TargetGroup {
+	tg := &config.TargetGroup{
+		Source: serviceSource(svc),
+	}
+	tg.Labels = serviceLabels(svc)
+	tg.Labels[namespaceLabel] = lv(svc.Namespace)
+
+	for _, port := range svc.Spec.Ports {
+		addr := net.JoinHostPort(svc.Name+"."+svc.Namespace+".svc", strconv.FormatInt(int64(port.Port), 10))
+
+		tg.Targets = append(tg.Targets, model.LabelSet{
+			model.AddressLabel:       lv(addr),
+			servicePortNameLabel:     lv(port.Name),
+			servicePortProtocolLabel: lv(string(port.Protocol)),
+		})
+	}
+
+	return tg
+}