Merge pull request #385 from arangodb/bug-fix/arangodb-exporter-fixes

Create headless service for exporter pods.

Author: neunhoef

pkg/apis/deployment/v1alpha/deployment_status.go

@@ -38,6 +38,8 @@ type DeploymentStatus struct {
 	// to access syncmasters (only set when dc2dc synchronization is enabled).
 	SyncServiceName string `json:"syncServiceName,omitempty"`
 
+	ExporterServiceName string `json:"exporterServiceName,omitempty"`
+
 	// Images holds a list of ArangoDB images with their ID and ArangoDB version.
 	Images ImageInfoList `json:"arangodb-images,omitempty"`
 	// Image that is currently being used when new pods are created
@@ -69,6 +71,7 @@ func (ds *DeploymentStatus) Equal(other DeploymentStatus) bool {
 		ds.Reason == other.Reason &&
 		ds.ServiceName == other.ServiceName &&
 		ds.SyncServiceName == other.SyncServiceName &&
+		ds.ExporterServiceName == other.ExporterServiceName &&
 		ds.Images.Equal(other.Images) &&
 		ds.CurrentImage.Equal(other.CurrentImage) &&
 		ds.Members.Equal(other.Members) &&

pkg/deployment/resources/services.go

@@ -25,7 +25,7 @@ package resources
 import (
 	"time"
 
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 
 	api "github.com/arangodb/kube-arangodb/pkg/apis/deployment/v1alpha"
@@ -117,6 +117,21 @@ func (r *Resources) EnsureServices() error {
 			}
 		}
 	}
+
+	if spec.Metrics.IsEnabled() {
+		name, _, err := k8sutil.CreateExporterService(svcs, apiObject, apiObject.AsOwner())
+		if err != nil {
+			log.Debug().Err(err).Msgf("Failed to create %s exporter service", name)
+			return maskAny(err)
+		}
+		status, lastVersion := r.context.GetStatus()
+		if status.ExporterServiceName != name {
+			status.ExporterServiceName = name
+			if err := r.context.UpdateStatus(status, lastVersion); err != nil {
+				return maskAny(err)
+			}
+		}
+	}
 	return nil
 }
 

pkg/util/k8sutil/services.go

@@ -29,7 +29,7 @@ import (
 	"strconv"
 	"strings"
 
-	"k8s.io/api/core/v1"
+	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
@@ -64,6 +64,45 @@ func CreateSyncMasterClientServiceName(deploymentName string) string {
 	return deploymentName + "-sync"
 }
 
+// CreateExporterClientServiceName returns the name of the service used by arangodb-exporter clients for the given
+// deployment name.
+func CreateExporterClientServiceName(deploymentName string) string {
+	return deploymentName + "-exporter"
+}
+
+// CreateExporterService
+func CreateExporterService(svcs ServiceInterface, deployment metav1.Object, owner metav1.OwnerReference) (string, bool, error) {
+	deploymentName := deployment.GetName()
+	svcName := CreateExporterClientServiceName(deploymentName)
+
+	selectorLabels := LabelsForExporterServiceSelector(deploymentName)
+
+	svc := &v1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:   svcName,
+			Labels: LabelsForExporterService(deploymentName),
+		},
+		Spec: v1.ServiceSpec{
+			ClusterIP: v1.ClusterIPNone,
+			Ports: []v1.ServicePort{
+				v1.ServicePort{
+					Name:     "exporter",
+					Protocol: v1.ProtocolTCP,
+					Port:     ArangoExporterPort,
+				},
+			},
+			Selector: selectorLabels,
+		},
+	}
+	addOwnerRefToObject(svc.GetObjectMeta(), &owner)
+	if _, err := svcs.Create(svc); IsAlreadyExists(err) {
+		return svcName, false, nil
+	} else if err != nil {
+		return svcName, false, maskAny(err)
+	}
+	return svcName, true, nil
+}
+
 // CreateHeadlessService prepares and creates a headless service in k8s, used to provide a stable
 // DNS name for all pods.
 // If the service already exists, nil is returned.

pkg/util/k8sutil/util.go

@@ -50,6 +50,22 @@ func addOwnerRefToObject(obj metav1.Object, ownerRef *metav1.OwnerReference) {
 	}
 }
 
+// LabelsForExporterServiceSelector returns a map of labels, used to select the all arangodb-exporter containers
+func LabelsForExporterServiceSelector(deploymentName string) map[string]string {
+	return map[string]string{
+		LabelKeyArangoDeployment: deploymentName,
+		LabelKeyArangoExporter:   "yes",
+	}
+}
+
+// LabelsForExporterService returns a map of labels, used to select the all arangodb-exporter containers
+func LabelsForExporterService(deploymentName string) map[string]string {
+	return map[string]string{
+		LabelKeyArangoDeployment: deploymentName,
+		LabelKeyApp:              AppName,
+	}
+}
+
 // LabelsForDeployment returns a map of labels, given to all resources for given deployment name
 func LabelsForDeployment(deploymentName, role string) map[string]string {
 	l := map[string]string{