Add --kube-context flag to CLI (#2019)

cli/cmd/root.go

@@ -29,15 +29,16 @@ Get started with Odigos today to effortlessly improve the observability of your
 		client := kube.GetCLIClientOrExit(cmd)
 		ctx = cmdcontext.ContextWithKubeClient(ctx, client)
 
-		details := autodetect.GetK8SClusterDetails(ctx, kubeConfig, client)
+		details := autodetect.GetK8SClusterDetails(ctx, kubeConfig, kubeContext, client)
 		ctx = cmdcontext.ContextWithClusterDetails(ctx, details)
 
 		cmd.SetContext(ctx)
 	},
 }
 
 var (
-	kubeConfig string
+	kubeConfig  string
+	kubeContext string
 )
 
 // Execute adds all child commands to the root command and sets flags appropriately.
@@ -51,4 +52,5 @@ func Execute() {
 
 func init() {
 	rootCmd.PersistentFlags().StringVar(&kubeConfig, "kubeconfig", env.GetDefaultKubeConfigPath(), "(optional) absolute path to the kubeconfig file")
+	rootCmd.PersistentFlags().StringVar(&kubeContext, "kube-context", "", "(optional) name of the kubeconfig context to use")
 }

cli/pkg/autodetect/kind.go

@@ -42,9 +42,9 @@ type ClusterDetails struct {
 	K8SVersion *version.Version
 }
 
-func GetK8SClusterDetails(ctx context.Context, kc string, client *kube.Client) *ClusterDetails {
+func GetK8SClusterDetails(ctx context.Context, kc string, kContext string, client *kube.Client) *ClusterDetails {
 	clusterDetails := &ClusterDetails{}
-	details := k8sutils.GetCurrentClusterDetails(kc)
+	details := k8sutils.GetCurrentClusterDetails(kc, kContext)
 	serverVersion, err := client.Discovery().ServerVersion()
 	if err != nil {
 		clusterDetails.K8SVersion = nil

cli/pkg/kube/client.go

@@ -57,8 +57,8 @@ func GetCLIClientOrExit(cmd *cobra.Command) *Client {
 
 func createClient(cmd *cobra.Command) (*Client, error) {
 	kc := cmd.Flag("kubeconfig").Value.String()
-
-	config, err := k8sutils.GetClientConfig(kc)
+	kContext := cmd.Flag("kube-context").Value.String()
+	config, err := k8sutils.GetClientConfigWithContext(kc, kContext)
 	if err != nil {
 		return nil, err
 	}

frontend/kube/client.go

@@ -32,8 +32,8 @@ type Client struct {
 	MetadataClient metadata.Interface
 }
 
-func CreateClient(kubeConfig string) (*Client, error) {
-	config, err := k8sutils.GetClientConfig(kubeConfig)
+func CreateClient(kubeConfig string, kContext string) (*Client, error) {
+	config, err := k8sutils.GetClientConfigWithContext(kubeConfig, kContext)
 	if err != nil {
 		return nil, err
 	}

frontend/main.go

@@ -46,13 +46,14 @@ const (
 )
 
 type Flags struct {
-	Version    bool
-	Address    string
-	Port       int
-	LegacyPort int
-	Debug      bool
-	KubeConfig string
-	Namespace  string
+	Version     bool
+	Address     string
+	Port        int
+	LegacyPort  int
+	Debug       bool
+	KubeConfig  string
+	KubeContext string
+	Namespace   string
 }
 
 //go:embed all:webapp/out/*
@@ -71,13 +72,14 @@ func parseFlags() Flags {
 	flag.IntVar(&flags.LegacyPort, "legacy-port", legacyPort, "Port to listen on for legacy UI")
 	flag.BoolVar(&flags.Debug, "debug", false, "Enable debug mode")
 	flag.StringVar(&flags.KubeConfig, "kubeconfig", defaultKubeConfig, "Path to kubeconfig file")
+	flag.StringVar(&flags.KubeContext, "kube-context", "", "Name of the kubeconfig context to use")
 	flag.StringVar(&flags.Namespace, "namespace", consts.DefaultOdigosNamespace, "Kubernetes namespace where Odigos is installed")
 	flag.Parse()
 	return flags
 }
 
 func initKubernetesClient(flags *Flags) error {
-	client, err := kube.CreateClient(flags.KubeConfig)
+	client, err := kube.CreateClient(flags.KubeConfig, flags.KubeContext)
 	if err != nil {
 		return fmt.Errorf("error creating Kubernetes client: %w", err)
 	}

k8sutils/pkg/client/client.go

@@ -1,24 +1,41 @@
 package client
 
 import (
+	"fmt"
 	"os"
 
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/clientcmd"
 )
 
-func GetClientConfig(kc string) (*rest.Config, error) {
+func GetClientConfigWithContext(kc string, context string) (*rest.Config, error) {
 	var kubeConfig *rest.Config
 	var err error
 
 	if IsRunningInKubernetes() {
+		// Running inside a Kubernetes cluster
 		kubeConfig, err = rest.InClusterConfig()
 		if err != nil {
 			return nil, err
 		}
 	} else {
-		kubeConfig, err = clientcmd.BuildConfigFromFlags("", kc)
+		// Loading kubeconfig from file with optional context override
+		loadingRules := &clientcmd.ClientConfigLoadingRules{
+			ExplicitPath: kc, // Path to kubeconfig
+		}
+
+		configOverrides := &clientcmd.ConfigOverrides{}
+		if context != "" {
+			configOverrides.CurrentContext = context
+		}
+
+		// Build the kubeconfig
+		kubeConfig, err = clientcmd.NewNonInteractiveDeferredLoadingClientConfig(
+			loadingRules,
+			configOverrides,
+		).ClientConfig()
+
 		if err != nil {
 			return nil, err
 		}
@@ -36,16 +53,24 @@ type ClusterDetails struct {
 	ServerEndpoint string
 }
 
-func GetCurrentClusterDetails(kc string) ClusterDetails {
+func GetCurrentClusterDetails(kc string, kContext string) ClusterDetails {
 	config, err := clientcmd.LoadFromFile(kc)
 	if err != nil {
 		return ClusterDetails{}
 	}
 
-	ctx := config.CurrentContext
+	var ctx string
+	if kContext != "" {
+		ctx = kContext
+	} else {
+		ctx = config.CurrentContext
+	}
 	cluster := ""
 	if val, ok := config.Contexts[ctx]; ok {
 		cluster = val.Cluster
+	} else if kContext != "" { // If context is provided, but not found in kubeconfig
+		fmt.Printf("Context %s not found in kubeconfig, bailing\n", kContext)
+		os.Exit(1)
 	}
 
 	server := ""