added support of multiple namespaces (#167)

cli/cmd/tap.go

@@ -56,7 +56,7 @@ func init() {
 	defaults.Set(&defaultTapConfig)
 
 	tapCmd.Flags().Uint16P(configStructs.GuiPortTapName, "p", defaultTapConfig.GuiPort, "Provide a custom port for the web interface webserver")
-	tapCmd.Flags().StringP(configStructs.NamespaceTapName, "n", defaultTapConfig.Namespace, "Namespace selector")
+	tapCmd.Flags().StringArrayP(configStructs.NamespacesTapName, "n", defaultTapConfig.Namespaces, "Namespaces selector")
 	tapCmd.Flags().Bool(configStructs.AnalysisTapName, defaultTapConfig.Analysis, "Uploads traffic to UP9 for further analysis (Beta)")
 	tapCmd.Flags().BoolP(configStructs.AllNamespacesTapName, "A", defaultTapConfig.AllNamespaces, "Tap all namespaces")
 	tapCmd.Flags().StringP(configStructs.KubeConfigPathTapName, "k", defaultTapConfig.KubeConfigPath, "Path to kube-config file")

cli/cmd/tapRunner.go

@@ -11,6 +11,7 @@ import (
 	"os/signal"
 	"path"
 	"regexp"
+	"strings"
 	"syscall"
 	"time"
 
@@ -65,24 +66,25 @@ func RunMizuTap() {
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel() // cancel will be called when this function exits
 
-	targetNamespace := getNamespace(kubernetesProvider)
+	targetNamespaces := getNamespaces(kubernetesProvider)
+
 	var namespacesStr string
-	if targetNamespace != mizu.K8sAllNamespaces {
+	if targetNamespaces[0] != mizu.K8sAllNamespaces {
-		namespacesStr = fmt.Sprintf("namespace \"%s\"", targetNamespace)
+		namespacesStr = fmt.Sprintf("namespaces \"%s\"", strings.Join(targetNamespaces, "\", \""))
 	} else {
 		namespacesStr = "all namespaces"
 	}
 	mizu.CheckNewerVersion()
 	mizu.Log.Infof("Tapping pods in %s", namespacesStr)
 
-	if err, _ := updateCurrentlyTappedPods(kubernetesProvider, ctx, targetNamespace); err != nil {
+	if err, _ := updateCurrentlyTappedPods(kubernetesProvider, ctx, targetNamespaces); err != nil {
 		mizu.Log.Errorf(uiUtils.Error, fmt.Sprintf("Error getting pods by regex: %v", errormessage.FormatError(err)))
 		return
 	}
 
 	if len(state.currentlyTappedPods) == 0 {
 		var suggestionStr string
-		if targetNamespace != mizu.K8sAllNamespaces {
+		if targetNamespaces[0] != mizu.K8sAllNamespaces {
 			suggestionStr = ". Select a different namespace with -n or tap all namespaces with -A"
 		}
 		mizu.Log.Warningf(uiUtils.Warning, fmt.Sprintf("Did not find any pods matching the regex argument%s", suggestionStr))
@@ -100,7 +102,7 @@ func RunMizuTap() {
 	}
 
 	go createProxyToApiServerPod(ctx, kubernetesProvider, cancel)
-	go watchPodsForTapping(ctx, kubernetesProvider, cancel)
+	go watchPodsForTapping(ctx, kubernetesProvider, targetNamespaces, cancel)
 
 	//block until exit signal or error
 	waitForFinish(ctx, cancel)
@@ -347,12 +349,11 @@ func reportTappedPods() {
 	}
 }
 
-func watchPodsForTapping(ctx context.Context, kubernetesProvider *kubernetes.Provider, cancel context.CancelFunc) {
+func watchPodsForTapping(ctx context.Context, kubernetesProvider *kubernetes.Provider, targetNamespaces []string, cancel context.CancelFunc) {
-	targetNamespace := getNamespace(kubernetesProvider)
+	added, modified, removed, errorChan := kubernetes.FilteredWatch(ctx, kubernetesProvider, targetNamespaces, mizu.Config.Tap.PodRegex())
-	added, modified, removed, errorChan := kubernetes.FilteredWatch(ctx, kubernetesProvider.GetPodWatcher(ctx, targetNamespace), mizu.Config.Tap.PodRegex())
 
 	restartTappers := func() {
-		err, changeFound := updateCurrentlyTappedPods(kubernetesProvider, ctx, targetNamespace)
+		err, changeFound := updateCurrentlyTappedPods(kubernetesProvider, ctx, targetNamespaces)
 		if err != nil {
 			mizu.Log.Errorf(uiUtils.Error, fmt.Sprintf("Error getting pods by regex: %v", errormessage.FormatError(err)))
 			cancel()
@@ -407,9 +408,9 @@ func watchPodsForTapping(ctx context.Context, kubernetesProvider *kubernetes.Pro
 	}
 }
 
-func updateCurrentlyTappedPods(kubernetesProvider *kubernetes.Provider, ctx context.Context, targetNamespace string) (error, bool) {
+func updateCurrentlyTappedPods(kubernetesProvider *kubernetes.Provider, ctx context.Context, targetNamespaces []string) (error, bool) {
 	changeFound := false
-	if matchingPods, err := kubernetesProvider.GetAllRunningPodsMatchingRegex(ctx, mizu.Config.Tap.PodRegex(), targetNamespace); err != nil {
+	if matchingPods, err := kubernetesProvider.GetAllRunningPodsMatchingRegex(ctx, mizu.Config.Tap.PodRegex(), targetNamespaces); err != nil {
 		return err, false
 	} else {
 		addedPods, removedPods := getPodArrayDiff(state.currentlyTappedPods, matchingPods)
@@ -454,7 +455,7 @@ func getMissingPods(pods1 []core.Pod, pods2 []core.Pod) []core.Pod {
 
 func createProxyToApiServerPod(ctx context.Context, kubernetesProvider *kubernetes.Provider, cancel context.CancelFunc) {
 	podExactRegex := regexp.MustCompile(fmt.Sprintf("^%s$", mizu.ApiServerPodName))
-	added, modified, removed, errorChan := kubernetes.FilteredWatch(ctx, kubernetesProvider.GetPodWatcher(ctx, mizu.Config.ResourcesNamespace()), podExactRegex)
+	added, modified, removed, errorChan := kubernetes.FilteredWatch(ctx, kubernetesProvider, []string{mizu.Config.ResourcesNamespace()}, podExactRegex)
 	isPodReady := false
 	timeAfter := time.After(25 * time.Second)
 	for {
@@ -567,12 +568,12 @@ func waitForFinish(ctx context.Context, cancel context.CancelFunc) {
 	}
 }
 
-func getNamespace(kubernetesProvider *kubernetes.Provider) string {
+func getNamespaces(kubernetesProvider *kubernetes.Provider) []string {
 	if mizu.Config.Tap.AllNamespaces {
-		return mizu.K8sAllNamespaces
+		return []string{mizu.K8sAllNamespaces}
-	} else if len(mizu.Config.Tap.Namespace) > 0 {
+	} else if len(mizu.Config.Tap.Namespaces) > 0 {
-		return mizu.Config.Tap.Namespace
+		return mizu.Config.Tap.Namespaces
 	} else {
-		return kubernetesProvider.CurrentNamespace()
+		return []string{kubernetesProvider.CurrentNamespace()}
 	}
 }

cli/kubernetes/provider.go

@@ -691,13 +691,19 @@ func (provider *Provider) ApplyMizuTapperDaemonSet(ctx context.Context, namespac
 	return err
 }
 
-func (provider *Provider) GetAllRunningPodsMatchingRegex(ctx context.Context, regex *regexp.Regexp, namespace string) ([]core.Pod, error) {
+func (provider *Provider) GetAllRunningPodsMatchingRegex(ctx context.Context, regex *regexp.Regexp, namespaces []string) ([]core.Pod, error) {
-	pods, err := provider.clientSet.CoreV1().Pods(namespace).List(ctx, metav1.ListOptions{})
+	var pods []core.Pod
+	for _, namespace := range namespaces {
+		namespacePods, err := provider.clientSet.CoreV1().Pods(namespace).List(ctx, metav1.ListOptions{})
 		if err != nil {
-		return nil, err
+			return nil, fmt.Errorf("failed to get pods in ns: %s, %w", namespace, err)
 		}
+
+		pods = append(pods, namespacePods.Items...)
+	}
+
 	matchingPods := make([]core.Pod, 0)
-	for _, pod := range pods.Items {
+	for _, pod := range pods {
 		if regex.MatchString(pod.Name) && isPodRunning(&pod) {
 			matchingPods = append(matchingPods, pod)
 		}

cli/kubernetes/watch.go

@@ -4,21 +4,30 @@ import (
 	"context"
 	"errors"
 	"regexp"
+	"sync"
 
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/watch"
 )
 
-func FilteredWatch(ctx context.Context, watcher watch.Interface, podFilter *regexp.Regexp) (chan *corev1.Pod, chan *corev1.Pod, chan *corev1.Pod, chan error) {
+func FilteredWatch(ctx context.Context, kubernetesProvider *Provider, targetNamespaces []string, podFilter *regexp.Regexp) (chan *corev1.Pod, chan *corev1.Pod, chan *corev1.Pod, chan error) {
 	addedChan := make(chan *corev1.Pod)
 	modifiedChan := make(chan *corev1.Pod)
 	removedChan := make(chan *corev1.Pod)
 	errorChan := make(chan error)
-	go func() {
+
+	var wg sync.WaitGroup
+
+	for _, targetNamespace := range targetNamespaces {
+		wg.Add(1)
+
+		go func(targetNamespace string) {
+			defer wg.Done()
+			watcher := kubernetesProvider.GetPodWatcher(ctx, targetNamespace)
+
 			for {
 				select {
 				case e := <-watcher.ResultChan():
-
 					if e.Object == nil {
 						errorChan <- errors.New("kubernetes pod watch failed")
 						return
@@ -40,13 +49,19 @@ func FilteredWatch(ctx context.Context, watcher watch.Interface, podFilter *rege
 					}
 				case <-ctx.Done():
 					watcher.Stop()
+					return
+				}
+			}
+		}(targetNamespace)
+	}
+
+	go func() {
+		<-ctx.Done()
+		wg.Wait()
 		close(addedChan)
 		close(modifiedChan)
 		close(removedChan)
 		close(errorChan)
-				return
-			}
-		}
 	}()
 
 	return addedChan, modifiedChan, removedChan, errorChan

cli/mizu/configStructs/tapConfig.go

@@ -11,7 +11,7 @@ import (
 
 const (
 	GuiPortTapName                = "gui-port"
-	NamespaceTapName              = "namespace"
+	NamespacesTapName             = "namespaces"
 	AnalysisTapName               = "analysis"
 	AllNamespacesTapName          = "all-namespaces"
 	KubeConfigPathTapName         = "kube-config"
@@ -29,7 +29,7 @@ type TapConfig struct {
 	SleepIntervalSec       int      `yaml:"upload-interval" default:"10"`
 	PodRegexStr            string   `yaml:"regex" default:".*"`
 	GuiPort                uint16   `yaml:"gui-port" default:"8899"`
-	Namespace              string   `yaml:"namespace"`
+	Namespaces             []string `yaml:"namespaces"`
 	Analysis               bool     `yaml:"analysis" default:"false"`
 	AllNamespaces          bool     `yaml:"all-namespaces" default:"false"`
 	KubeConfigPath         string   `yaml:"kube-config"`