Select node by pod (#18)

* Select node by pod.

* Removed watch pod by regex. Irrelevant for now.

* Changed default image to develop:latest.

cli/cmd/root.go

@@ -1,11 +1,9 @@
 package cmd
 
 import (
-	"fmt"
 	"github.com/spf13/cobra"
 	"github.com/up9inc/mizu/cli/config"
 	"github.com/up9inc/mizu/cli/mizu"
-	"regexp"
 )
 
 // rootCmd represents the base command when called without any subcommands
@@ -16,16 +14,11 @@ func init() {
 	rootCmd.Use = "cmd pod-query"
 	rootCmd.Short = "Tail HTTP traffic from multiple pods"
 	rootCmd.RunE = func(cmd *cobra.Command, args []string) error {
-		if len(args) != 1 {
+		if len(args) != 0 {
 			return rootCmd.Help()
 		}
 
-		regex, err := regexp.Compile(args[0])
+		mizu.Run()
-		if err != nil {
-			fmt.Printf("%s is not a valid regex %s", args[0], err)
-			return nil
-		}
-		mizu.Run(regex)
 		return nil
 	}
 
@@ -36,8 +29,9 @@ func init() {
 	rootCmd.Flags().StringVarP(&config.Configuration.Namespace, "namespace", "n", "", "Namespace selector")
 	rootCmd.Flags().BoolVarP(&config.Configuration.AllNamespaces, "all-namespaces", "A", false, "Select all namespaces")
 	rootCmd.Flags().StringVarP(&config.Configuration.KubeConfigPath, "kubeconfig", "k", "", "Path to kubeconfig file")
-	rootCmd.Flags().StringVarP(&config.Configuration.MizuImage, "mizu-image", "", "gcr.io/up9-docker-hub/mizu/develop/v6", "Custom image for mizu collector")
+	rootCmd.Flags().StringVarP(&config.Configuration.MizuImage, "mizu-image", "", "gcr.io/up9-docker-hub/mizu/develop:latest", "Custom image for mizu collector")
 	rootCmd.Flags().Uint16VarP(&config.Configuration.MizuPodPort, "mizu-port", "", 8899, "Port which mizu cli will attempt to forward from the mizu collector pod")
+	rootCmd.Flags().StringVarP(&config.Configuration.TappedPodName, "pod", "", "", "View traffic of this pod")
 }
 
 // Execute adds all child commands to the root command and sets flags appropriately.

cli/config/config.go

@@ -10,6 +10,7 @@ type Options struct {
 	KubeConfigPath   string
 	MizuImage        string
 	MizuPodPort      uint16
+	TappedPodName	string
 }
 
 var Configuration = &Options{}

cli/kubernetes/provider.go

@@ -70,7 +70,12 @@ func (provider *Provider) GetPods(ctx context.Context) {
 	fmt.Printf("There are %d pods in Namespace %s\n", len(pods.Items), provider.Namespace)
 }
 
-func (provider *Provider) CreatePod(ctx context.Context, podName string, podImage string) (*core.Pod, error) {
+func (provider *Provider) CreateMizuPod(ctx context.Context, podName string, podImage string, tappedPodName string) (*core.Pod, error) {
+	tappedPod, err := provider.clientSet.CoreV1().Pods(provider.Namespace).Get(ctx, tappedPodName, metav1.GetOptions{})
+	if err != nil {
+		panic(err.Error())
+	}
+
 	privileged := true
 	pod := &core.Pod{
 		ObjectMeta: metav1.ObjectMeta{
@@ -96,6 +101,7 @@ func (provider *Provider) CreatePod(ctx context.Context, podName string, podImag
 				},
 			},
 			TerminationGracePeriodSeconds: new(int64),
+			NodeSelector: map[string]string{"kubernetes.io/hostname": tappedPod.Spec.NodeName},
 		},
 	}
 	return provider.clientSet.CoreV1().Pods(provider.Namespace).Create(ctx, pod, metav1.CreateOptions{})

cli/mizu/mizuRunner.go

@@ -12,7 +12,7 @@ import (
 	"time"
 )
 
-func Run(podRegex *regexp.Regexp) {
+func Run() {
 	kubernetesProvider := kubernetes.NewProvider(config.Configuration.KubeConfigPath, config.Configuration.Namespace)
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel() // cancel will be called when this function exits
@@ -20,7 +20,6 @@ func Run(podRegex *regexp.Regexp) {
 	podName := "mizu-collector"
 
 	go createPodAndPortForward(ctx, kubernetesProvider, cancel, podName) //TODO convert this to job for built in pod ttl or have the running app handle this
-	go watchPodsForTapping(ctx, kubernetesProvider, cancel, podRegex)
 	waitForFinish(ctx, cancel) //block until exit signal or error
 
 	// TODO handle incoming traffic from tapper using a channel
@@ -54,7 +53,7 @@ func watchPodsForTapping(ctx context.Context, kubernetesProvider *kubernetes.Pro
 }
 
 func createPodAndPortForward(ctx context.Context, kubernetesProvider *kubernetes.Provider, cancel context.CancelFunc, podName string) {
-	pod, err := kubernetesProvider.CreatePod(ctx, podName, config.Configuration.MizuImage)
+	pod, err := kubernetesProvider.CreateMizuPod(ctx, podName, config.Configuration.MizuImage, config.Configuration.TappedPodName)
 	if err != nil {
 		fmt.Printf("error creating pod %s", err)
 		cancel()