Refactor `getComponentCommand()` for readability

cmd/kubeadm/app/master/addons.go

@@ -43,7 +43,7 @@ func createKubeProxyPodSpec(cfg *kubeadmapi.MasterConfiguration, architecture st
 		Containers: []api.Container{{
 			Name:            kubeProxy,
 			Image:           images.GetCoreImage(images.KubeProxyImage, cfg, envParams["hyperkube_image"]),
-			Command:         append(getComponentCommand("proxy", cfg), "--kubeconfig=/run/kubeconfig"),
+			Command:         append(getProxyCommand(cfg), "--kubeconfig=/run/kubeconfig"),
 			SecurityContext: &api.SecurityContext{Privileged: &privilegedTrue},
 			VolumeMounts: []api.VolumeMount{
 				{

cmd/kubeadm/app/master/manifests.go

@@ -60,7 +60,7 @@ func WriteStaticPodManifests(cfg *kubeadmapi.MasterConfiguration) error {
 		kubeAPIServer: componentPod(api.Container{
 			Name:          kubeAPIServer,
 			Image:         images.GetCoreImage(images.KubeAPIServerImage, cfg, envParams["hyperkube_image"]),
-			Command:       getComponentCommand(apiServer, cfg),
+			Command:       getAPIServerCommand(cfg),
 			VolumeMounts:  []api.VolumeMount{certsVolumeMount(), k8sVolumeMount()},
 			LivenessProbe: componentProbe(8080, "/healthz"),
 			Resources:     componentResources("250m"),
@@ -68,7 +68,7 @@ func WriteStaticPodManifests(cfg *kubeadmapi.MasterConfiguration) error {
 		kubeControllerManager: componentPod(api.Container{
 			Name:          kubeControllerManager,
 			Image:         images.GetCoreImage(images.KubeControllerManagerImage, cfg, envParams["hyperkube_image"]),
-			Command:       getComponentCommand(controllerManager, cfg),
+			Command:       getControllerManagerCommand(cfg),
 			VolumeMounts:  []api.VolumeMount{certsVolumeMount(), k8sVolumeMount()},
 			LivenessProbe: componentProbe(10252, "/healthz"),
 			Resources:     componentResources("200m"),
@@ -76,7 +76,7 @@ func WriteStaticPodManifests(cfg *kubeadmapi.MasterConfiguration) error {
 		kubeScheduler: componentPod(api.Container{
 			Name:          kubeScheduler,
 			Image:         images.GetCoreImage(images.KubeSchedulerImage, cfg, envParams["hyperkube_image"]),
-			Command:       getComponentCommand(scheduler, cfg),
+			Command:       getSchedulerCommand(cfg),
 			LivenessProbe: componentProbe(10251, "/healthz"),
 			Resources:     componentResources("100m"),
 		}),
@@ -221,88 +221,100 @@ func componentPod(container api.Container, volumes ...api.Volume) api.Pod {
 	}
 }
 
-func getComponentCommand(component string, cfg *kubeadmapi.MasterConfiguration) (command []string) {
-	baseFlags := map[string][]string{
-		apiServer: {
-			"--insecure-bind-address=127.0.0.1",
-			"--admission-control=NamespaceLifecycle,LimitRanger,ServiceAccount,PersistentVolumeLabel,DefaultStorageClass,ResourceQuota",
-			"--service-cluster-ip-range=" + cfg.Networking.ServiceSubnet,
-			"--service-account-key-file=" + pkiDir + "/apiserver-key.pem",
-			"--client-ca-file=" + pkiDir + "/ca.pem",
-			"--tls-cert-file=" + pkiDir + "/apiserver.pem",
-			"--tls-private-key-file=" + pkiDir + "/apiserver-key.pem",
-			"--token-auth-file=" + pkiDir + "/tokens.csv",
-			fmt.Sprintf("--secure-port=%d", cfg.API.BindPort),
-			"--allow-privileged",
-		},
-		controllerManager: {
-			"--address=127.0.0.1",
-			"--leader-elect",
-			"--master=127.0.0.1:8080",
-			"--cluster-name=" + DefaultClusterName,
-			"--root-ca-file=" + pkiDir + "/ca.pem",
-			"--service-account-private-key-file=" + pkiDir + "/apiserver-key.pem",
-			"--cluster-signing-cert-file=" + pkiDir + "/ca.pem",
-			"--cluster-signing-key-file=" + pkiDir + "/ca-key.pem",
-			"--insecure-experimental-approve-all-kubelet-csrs-for-group=system:kubelet-bootstrap",
-		},
-		scheduler: {
-			"--address=127.0.0.1",
-			"--leader-elect",
-			"--master=127.0.0.1:8080",
-		},
-		proxy: {},
-	}
-
+func getComponentBaseCommand(component string) (command []string) {
 	envParams := kubeadmapi.GetEnvParams()
 	if envParams["hyperkube_image"] != "" {
 		command = []string{"/hyperkube", component}
 	} else {
-		command = []string{"/usr/local/bin/kube-" + component}
+		command = []string{"kube-" + component}
 	}
-
 	command = append(command, envParams["component_loglevel"])
-	command = append(command, baseFlags[component]...)
+	return
+}
 
-	if component == apiServer {
-		// Use first address we are given
-		if len(cfg.API.AdvertiseAddresses) > 0 {
-			command = append(command, fmt.Sprintf("--advertise-address=%s", cfg.API.AdvertiseAddresses[0]))
-		}
-		// Check if the user decided to use an external etcd cluster
-		if len(cfg.Etcd.Endpoints) > 0 {
-			command = append(command, fmt.Sprintf("--etcd-servers=%s", strings.Join(cfg.Etcd.Endpoints, ",")))
-		} else {
-			command = append(command, "--etcd-servers=http://127.0.0.1:2379")
-		}
+func getAPIServerCommand(cfg *kubeadmapi.MasterConfiguration) (command []string) {
+	command = append(getComponentBaseCommand(apiServer),
+		"--insecure-bind-address=127.0.0.1",
+		"--admission-control=NamespaceLifecycle,LimitRanger,ServiceAccount,PersistentVolumeLabel,DefaultStorageClass,ResourceQuota",
+		"--service-cluster-ip-range="+cfg.Networking.ServiceSubnet,
+		"--service-account-key-file="+pkiDir+"/apiserver-key.pem",
+		"--client-ca-file="+pkiDir+"/ca.pem",
+		"--tls-cert-file="+pkiDir+"/apiserver.pem",
+		"--tls-private-key-file="+pkiDir+"/apiserver-key.pem",
+		"--token-auth-file="+pkiDir+"/tokens.csv",
+		fmt.Sprintf("--secure-port=%d", cfg.API.BindPort),
+		"--allow-privileged",
+	)
 
-		// Is etcd secured?
-		if cfg.Etcd.CAFile != "" {
-			command = append(command, fmt.Sprintf("--etcd-cafile=%s", cfg.Etcd.CAFile))
-		}
-		if cfg.Etcd.CertFile != "" && cfg.Etcd.KeyFile != "" {
-			etcdClientFileArg := fmt.Sprintf("--etcd-certfile=%s", cfg.Etcd.CertFile)
-			etcdKeyFileArg := fmt.Sprintf("--etcd-keyfile=%s", cfg.Etcd.KeyFile)
-			command = append(command, etcdClientFileArg, etcdKeyFileArg)
-		}
+	// Use first address we are given
+	if len(cfg.API.AdvertiseAddresses) > 0 {
+		command = append(command, fmt.Sprintf("--advertise-address=%s", cfg.API.AdvertiseAddresses[0]))
 	}
 
-	if component == controllerManager {
-		if cfg.CloudProvider != "" {
-			command = append(command, "--cloud-provider="+cfg.CloudProvider)
+	// Check if the user decided to use an external etcd cluster
+	if len(cfg.Etcd.Endpoints) > 0 {
+		command = append(command, fmt.Sprintf("--etcd-servers=%s", strings.Join(cfg.Etcd.Endpoints, ",")))
+	} else {
+		command = append(command, "--etcd-servers=http://127.0.0.1:2379")
+	}
 
-			// Only append the --cloud-config option if there's a such file
-			// TODO(phase1+) this won't work unless it's in one of the few directories we bind-mount
-			if _, err := os.Stat(DefaultCloudConfigPath); err == nil {
-				command = append(command, "--cloud-config="+DefaultCloudConfigPath)
-			}
-		}
-		// Let the controller-manager allocate Node CIDRs for the Pod network.
-		// Each node will get a subspace of the address CIDR provided with --pod-network-cidr.
-		if cfg.Networking.PodSubnet != "" {
-			command = append(command, "--allocate-node-cidrs=true", "--cluster-cidr="+cfg.Networking.PodSubnet)
+	// Is etcd secured?
+	if cfg.Etcd.CAFile != "" {
+		command = append(command, fmt.Sprintf("--etcd-cafile=%s", cfg.Etcd.CAFile))
+	}
+	if cfg.Etcd.CertFile != "" && cfg.Etcd.KeyFile != "" {
+		etcdClientFileArg := fmt.Sprintf("--etcd-certfile=%s", cfg.Etcd.CertFile)
+		etcdKeyFileArg := fmt.Sprintf("--etcd-keyfile=%s", cfg.Etcd.KeyFile)
+		command = append(command, etcdClientFileArg, etcdKeyFileArg)
+	}
+
+	return
+}
+
+func getControllerManagerCommand(cfg *kubeadmapi.MasterConfiguration) (command []string) {
+	command = append(getComponentBaseCommand(controllerManager),
+		"--address=127.0.0.1",
+		"--leader-elect",
+		"--master=127.0.0.1:8080",
+		"--cluster-name="+DefaultClusterName,
+		"--root-ca-file="+pkiDir+"/ca.pem",
+		"--service-account-private-key-file="+pkiDir+"/apiserver-key.pem",
+		"--cluster-signing-cert-file="+pkiDir+"/ca.pem",
+		"--cluster-signing-key-file="+pkiDir+"/ca-key.pem",
+		"--insecure-experimental-approve-all-kubelet-csrs-for-group=system:kubelet-bootstrap",
+	)
+
+	if cfg.CloudProvider != "" {
+		command = append(command, "--cloud-provider="+cfg.CloudProvider)
+
+		// Only append the --cloud-config option if there's a such file
+		// TODO(phase1+) this won't work unless it's in one of the few directories we bind-mount
+		if _, err := os.Stat(DefaultCloudConfigPath); err == nil {
+			command = append(command, "--cloud-config="+DefaultCloudConfigPath)
 		}
 	}
 
+	// Let the controller-manager allocate Node CIDRs for the Pod network.
+	// Each node will get a subspace of the address CIDR provided with --pod-network-cidr.
+	if cfg.Networking.PodSubnet != "" {
+		command = append(command, "--allocate-node-cidrs=true", "--cluster-cidr="+cfg.Networking.PodSubnet)
+	}
+
+	return
+}
+
+func getSchedulerCommand(cfg *kubeadmapi.MasterConfiguration) (command []string) {
+	command = append(getComponentBaseCommand(scheduler),
+		"--address=127.0.0.1",
+		"--leader-elect",
+		"--master=127.0.0.1:8080",
+	)
+
+	return
+}
+
+func getProxyCommand(cfg *kubeadmapi.MasterConfiguration) (command []string) {
+	command = getComponentBaseCommand(proxy)
+
 	return
 }