add selector for istioctl dashboard (istio#19191)

Author: ckcd

istioctl/cmd/dashboard.go

@@ -31,6 +31,9 @@ import (
 
 var (
 	controlZport = 0
+
+	// label selector
+	labelSelector = ""
 )
 
 // port-forward to Istio System Prometheus; open browser
@@ -261,17 +264,43 @@ func envoyDashCmd() *cobra.Command {
 		Long:    `Open the Envoy admin dashboard for a sidecar`,
 		Example: `istioctl dashboard envoy productpage-123-456.default`,
 		RunE: func(c *cobra.Command, args []string) error {
-			if len(args) < 1 {
+			if labelSelector == "" && len(args) < 1 {
 				c.Println(c.UsageString())
-				return fmt.Errorf("specify a pod")
+				return fmt.Errorf("specify a pod or --selector")
+			}
+
+			if labelSelector != "" && len(args) > 0 {
+				c.Println(c.UsageString())
+				return fmt.Errorf("name cannot be provided when a selector is specified")
 			}
 
-			podName, ns := handlers.InferPodInfo(args[0], handlers.HandleNamespace(namespace, defaultNamespace))
 			client, err := clientExecFactory(kubeconfig, configContext)
 			if err != nil {
 				return fmt.Errorf("failed to create k8s client: %v", err)
 			}
 
+			var podName, ns string
+			if labelSelector != "" {
+				pl, err := client.PodsForSelector(handlers.HandleNamespace(namespace, defaultNamespace), labelSelector)
+				if err != nil {
+					return fmt.Errorf("not able to locate pod with selector %s: %v", labelSelector, err)
+				}
+
+				if len(pl.Items) < 1 {
+					return errors.New("no pods found")
+				}
+
+				if len(pl.Items) > 1 {
+					log.Warnf("more than 1 pods fits selector: %s; will use pod: %s", labelSelector, pl.Items[0].Name)
+				}
+
+				// only use the first pod in the list
+				podName = pl.Items[0].Name
+				ns = pl.Items[0].Namespace
+			} else {
+				podName, ns = handlers.InferPodInfo(args[0], handlers.HandleNamespace(namespace, defaultNamespace))
+			}
+
 			fw, err := client.BuildPortForwarder(podName, ns, 0, 15000)
 			if err != nil {
 				return fmt.Errorf("could not build port forwarder for %s: %v", podName, err)
@@ -300,17 +329,43 @@ func controlZDashCmd() *cobra.Command {
 		Long:    `Open the ControlZ web UI for a pod in the Istio control plane`,
 		Example: `istioctl dashboard controlz pilot-123-456.istio-system`,
 		RunE: func(c *cobra.Command, args []string) error {
-			if len(args) < 1 {
+			if labelSelector == "" && len(args) < 1 {
 				c.Println(c.UsageString())
-				return fmt.Errorf("specify a pod")
+				return fmt.Errorf("specify a pod or --selector")
+			}
+
+			if labelSelector != "" && len(args) > 0 {
+				c.Println(c.UsageString())
+				return fmt.Errorf("name cannot be provided when a selector is specified")
 			}
 
-			podName, ns := handlers.InferPodInfo(args[0], handlers.HandleNamespace(namespace, defaultNamespace))
 			client, err := clientExecFactory(kubeconfig, configContext)
 			if err != nil {
 				return fmt.Errorf("failed to create k8s client: %v", err)
 			}
 
+			var podName, ns string
+			if labelSelector != "" {
+				pl, err := client.PodsForSelector(handlers.HandleNamespace(namespace, defaultNamespace), labelSelector)
+				if err != nil {
+					return fmt.Errorf("not able to locate pod with selector %s: %v", labelSelector, err)
+				}
+
+				if len(pl.Items) < 1 {
+					return errors.New("no pods found")
+				}
+
+				if len(pl.Items) > 1 {
+					log.Warnf("more than 1 pods fits selector: %s; will use pod: %s", labelSelector, pl.Items[0].Name)
+				}
+
+				// only use the first pod in the list
+				podName = pl.Items[0].Name
+				ns = pl.Items[0].Namespace
+			} else {
+				podName, ns = handlers.InferPodInfo(args[0], handlers.HandleNamespace(namespace, defaultNamespace))
+			}
+
 			fw, err := client.BuildPortForwarder(podName, ns, 0, controlZport)
 			if err != nil {
 				return fmt.Errorf("could not build port forwarder for %s: %v", podName, err)
@@ -374,9 +429,13 @@ func dashboard() *cobra.Command {
 	dashboardCmd.AddCommand(jaegerDashCmd())
 	dashboardCmd.AddCommand(zipkinDashCmd())
 
-	dashboardCmd.AddCommand(envoyDashCmd())
+	envoy := envoyDashCmd()
+	envoy.PersistentFlags().StringVarP(&labelSelector, "selector", "l", "", "label selector")
+	dashboardCmd.AddCommand(envoy)
+
 	controlz := controlZDashCmd()
 	controlz.PersistentFlags().IntVar(&controlZport, "ctrlz_port", 9876, "ControlZ port")
+	controlz.PersistentFlags().StringVarP(&labelSelector, "selector", "l", "", "label selector")
 	dashboardCmd.AddCommand(controlz)
 
 	return dashboardCmd

istioctl/cmd/dashboard_test.go

@@ -38,7 +38,7 @@ func TestDashboard(t *testing.T) {
 		},
 		{ // case 2
 			args:           strings.Split("dashboard controlz", " "),
-			expectedRegexp: regexp.MustCompile(".*Error: specify a pod"),
+			expectedRegexp: regexp.MustCompile(".*Error: specify a pod or --selector"),
 			wantException:  true,
 		},
 		{ // case 3
@@ -48,7 +48,7 @@ func TestDashboard(t *testing.T) {
 		},
 		{ // case 4
 			args:           strings.Split("dashboard envoy", " "),
-			expectedRegexp: regexp.MustCompile(".*Error: specify a pod"),
+			expectedRegexp: regexp.MustCompile(".*Error: specify a pod or --selector"),
 			wantException:  true,
 		},
 		{ // case 5
@@ -86,6 +86,26 @@ func TestDashboard(t *testing.T) {
 			expectedOutput: "Error: (dashboard has graduated.  Use `istioctl dashboard`)\n",
 			wantException:  true,
 		},
+		{ // case 12
+			args:           strings.Split("dashboard envoy --selector app=example", " "),
+			expectedRegexp: regexp.MustCompile(".*no pods found"),
+			wantException:  true,
+		},
+		{ // case 13
+			args:           strings.Split("dashboard envoy --selector app=example pod-123456-7890", " "),
+			expectedRegexp: regexp.MustCompile(".*Error: name cannot be provided when a selector is specified"),
+			wantException:  true,
+		},
+		{ // case 14
+			args:           strings.Split("dashboard controlz --selector app=example", " "),
+			expectedRegexp: regexp.MustCompile(".*no pods found"),
+			wantException:  true,
+		},
+		{ // case 15
+			args:           strings.Split("dashboard controlz --selector app=example pod-123456-7890", " "),
+			expectedRegexp: regexp.MustCompile(".*Error: name cannot be provided when a selector is specified"),
+			wantException:  true,
+		},
 	}
 
 	for i, c := range cases {