Add service for envchecker ds

cluster/command.go

@@ -2,10 +2,11 @@ package cluster
 
 import (
 	"context"
-
+	"k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
 	appsv1 "k8s.io/client-go/kubernetes/typed/apps/v1"
+	corev1 "k8s.io/client-go/kubernetes/typed/core/v1"
 	"k8s.io/client-go/tools/clientcmd"
 )
 
@@ -22,28 +23,43 @@ func NewCommand(kubeconfig string) (*KubernetesCommand, error) {
 		return nil, err
 	}
 
-	return &KubernetesCommand{clientset.AppsV1()}, nil
+	return &KubernetesCommand{clientset.AppsV1(), clientset.CoreV1()}, nil
 }
 
 // Command provides an interface for creating envcheck entities in a cluster.
 type Command interface {
 	CreateDaemon(DaemonConfig) error
 	CreatePinger(PingerConfig) error
+	CreateService(DaemonConfig) error
 }
 
 // KubernetesCommand is a k8s implementation of the Command interface.
 type KubernetesCommand struct {
 	appsv1.AppsV1Interface
+	corev1.CoreV1Interface
 }
 
-// CreateDaemon applies a envchecker daemonset config to the current K8S environment.
+// CreateDaemon creates an envchecker daemonset in the current K8S environment.
 func (kc *KubernetesCommand) CreateDaemon(config DaemonConfig) error {
 	_, err := kc.DaemonSets(config.Namespace).Create(context.TODO(), Daemon(config), metav1.CreateOptions{})
+	if err != nil && errors.IsAlreadyExists(err) {
+		_, err = kc.DaemonSets(config.Namespace).Update(context.TODO(), Daemon(config), metav1.UpdateOptions{})
+	}
+	return err
+}
+
+// CreateService creates an envchecker service in the current K8S environment.
+func (kc *KubernetesCommand) CreateService(config DaemonConfig) error {
+	svc := Service(config)
+	_, err := kc.Services(config.Namespace).Create(context.TODO(), svc, metav1.CreateOptions{})
 	return err
 }
 
-// CreatePinger applies a pinger daemonset config to the current K8S environment.
+// CreatePinger creates a pinger daemonset in the current K8S environment.
 func (kc *KubernetesCommand) CreatePinger(config PingerConfig) error {
 	_, err := kc.DaemonSets(config.Namespace).Create(context.TODO(), Pinger(config), metav1.CreateOptions{})
+	if err != nil && errors.IsAlreadyExists(err) {
+		_, err = kc.DaemonSets(config.Namespace).Update(context.TODO(), Pinger(config), metav1.UpdateOptions{})
+	}
 	return err
 }

cluster/resources.go

@@ -2,6 +2,7 @@ package cluster
 
 import (
 	"fmt"
+	"k8s.io/apimachinery/pkg/util/intstr"
 
 	appsv1 "k8s.io/api/apps/v1"
 	v1 "k8s.io/api/core/v1"
@@ -41,6 +42,36 @@ const (
 	LabelVersion = "app.kubernetes.io/version"
 )
 
+var Local = v1.ServiceInternalTrafficPolicyLocal
+
+func Service(config DaemonConfig) *v1.Service {
+	return &v1.Service{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      DaemonSetName,
+			Namespace: config.Namespace,
+			Labels: map[string]string{
+				LabelManagedBy: ManagedBy,
+				LabelName:      DaemonSetName,
+				LabelVersion:   config.Version,
+			},
+		},
+		Spec: v1.ServiceSpec{
+			Selector: map[string]string{
+				LabelName: DaemonSetName,
+			},
+			InternalTrafficPolicy: &Local,
+			Ports: []v1.ServicePort{
+				{
+					Name:       "http",
+					Protocol:   v1.ProtocolTCP,
+					TargetPort: intstr.FromString("http"),
+					Port:       config.Port,
+				},
+			},
+		},
+	}
+}
+
 // Daemon creates the envchecker daemon set resource from the provided DaemonConfig.
 func Daemon(config DaemonConfig) *appsv1.DaemonSet {
 	return &appsv1.DaemonSet{
@@ -51,8 +82,7 @@ func Daemon(config DaemonConfig) *appsv1.DaemonSet {
 		Spec: appsv1.DaemonSetSpec{
 			Selector: &metav1.LabelSelector{
 				MatchLabels: map[string]string{
-					LabelName:    DaemonSetName,
-					LabelVersion: config.Version,
+					LabelName: DaemonSetName,
 				},
 			},
 			Template: v1.PodTemplateSpec{

cmd/envcheckctl/exec_daemon.go

@@ -20,7 +20,13 @@ func ExecDaemon(config EnvcheckConfig) {
 		Version:   Revision,
 	}
 	err = command.CreateDaemon(dc)
+
 	if err != nil {
 		log.Fatalf("createDaemon=failed err='%v'\n", err)
 	}
+
+	err = command.CreateService(dc)
+	if err != nil {
+		log.Fatalf("createService=failed err='%v'\n", err)
+	}
 }