Making kube config errors more user friendly (#132)

* Making kube config errors more user friendly

cli/cmd/tapRunner.go

@@ -9,6 +9,7 @@ import (
 	"github.com/up9inc/mizu/shared"
 	"github.com/up9inc/mizu/shared/debounce"
 	core "k8s.io/api/core/v1"
+	"k8s.io/client-go/tools/clientcmd"
 	"k8s.io/apimachinery/pkg/util/wait"
 	"log"
 	"net/http"
@@ -36,7 +37,17 @@ func RunMizuTap(podRegexQuery *regexp.Regexp, tappingOptions *MizuTapOptions) {
 		return
 	}
 
-	kubernetesProvider := kubernetes.NewProvider(tappingOptions.KubeConfigPath)
+	kubernetesProvider, err := kubernetes.NewProvider(tappingOptions.KubeConfigPath)
+	if err != nil {
+		if clientcmd.IsEmptyConfig(err) {
+			fmt.Printf(mizu.Red, "Couldn't find the kube config file, or file is empty. Try adding '--kube-config=<path to kube config file>'\n")
+			return
+		}
+		if clientcmd.IsConfigurationInvalid(err) {
+			fmt.Printf(mizu.Red, "Invalid kube config file. Try using a different config with '--kube-config=<path to kube config file>'\n")
+			return
+		}
+	}
 
 	defer cleanUpMizuResources(kubernetesProvider)
 	ctx, cancel := context.WithCancel(context.Background())

cli/cmd/view.go

@@ -7,6 +7,7 @@ import (
 
 type MizuViewOptions struct {
 	GuiPort        uint16
+	KubeConfigPath string
 }
 
 var mizuViewOptions = &MizuViewOptions{}
@@ -15,8 +16,8 @@ var viewCmd = &cobra.Command{
 	Use:   "view",
 	Short: "Open GUI in browser",
 	RunE: func(cmd *cobra.Command, args []string) error {
-		go mizu.ReportRun("view", mizuFetchOptions)
+		go mizu.ReportRun("view", mizuViewOptions)
-		if isCompatible, err := mizu.CheckVersionCompatibility(mizuFetchOptions.MizuPort); err != nil {
+		if isCompatible, err := mizu.CheckVersionCompatibility(mizuViewOptions.GuiPort); err != nil {
 			return err
 		} else if !isCompatible {
 			return nil
@@ -30,5 +31,5 @@ func init() {
 	rootCmd.AddCommand(viewCmd)
 
 	viewCmd.Flags().Uint16VarP(&mizuViewOptions.GuiPort, "gui-port", "p", 8899, "Provide a custom port for the web interface webserver")
-
+	viewCmd.Flags().StringVarP(&mizuViewOptions.KubeConfigPath, "kube-config", "k", "", "Path to kube-config file")
 }

cli/cmd/viewRunner.go

@@ -5,11 +5,22 @@ import (
 	"fmt"
 	"github.com/up9inc/mizu/cli/kubernetes"
 	"github.com/up9inc/mizu/cli/mizu"
+	"k8s.io/client-go/tools/clientcmd"
 	"net/http"
 )
 
 func runMizuView(mizuViewOptions *MizuViewOptions) {
-	kubernetesProvider := kubernetes.NewProvider("")
+	kubernetesProvider, err := kubernetes.NewProvider(mizuViewOptions.KubeConfigPath)
+	if err != nil {
+		if clientcmd.IsEmptyConfig(err) {
+			fmt.Printf(mizu.Red, "Couldn't find the kube config file, or file is empty. Try adding '--kube-config=<path to kube config file>'\n")
+			return
+		}
+		if clientcmd.IsConfigurationInvalid(err) {
+			fmt.Printf(mizu.Red, "Invalid kube config file. Try using a different config with '--kube-config=<path to kube config file>'\n")
+			return
+		}
+	}
 
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()

cli/kubernetes/provider.go

@@ -6,6 +6,8 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/client-go/tools/cache"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -17,7 +19,6 @@ import (
 	k8serrors "k8s.io/apimachinery/pkg/api/errors"
 	resource "k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/util/intstr"
 	"k8s.io/apimachinery/pkg/watch"
 	applyconfapp "k8s.io/client-go/applyconfigurations/apps/v1"
@@ -29,7 +30,6 @@ import (
 	_ "k8s.io/client-go/plugin/pkg/client/auth/oidc"
 	_ "k8s.io/client-go/plugin/pkg/client/auth/openstack"
 	restclient "k8s.io/client-go/rest"
-	"k8s.io/client-go/tools/cache"
 	"k8s.io/client-go/tools/clientcmd"
 	_ "k8s.io/client-go/tools/portforward"
 	watchtools "k8s.io/client-go/tools/watch"
@@ -47,14 +47,11 @@ const (
 	fieldManagerName = "mizu-manager"
 )
 
-func NewProvider(kubeConfigPath string) *Provider {
+func NewProvider(kubeConfigPath string) (*Provider, error) {
-	if kubeConfigPath == "" {
-		kubeConfigPath = os.Getenv("KUBECONFIG")
-	}
 	kubernetesConfig := loadKubernetesConfiguration(kubeConfigPath)
 	restClientConfig, err := kubernetesConfig.ClientConfig()
 	if err != nil {
-		panic(err.Error())
+		return nil, err
 	}
 	clientSet := getClientSet(restClientConfig)
 
@@ -62,7 +59,7 @@ func NewProvider(kubeConfigPath string) *Provider {
 		clientSet:        clientSet,
 		kubernetesConfig: kubernetesConfig,
 		clientConfig:     *restClientConfig,
-	}
+	}, nil
 }
 
 func (provider *Provider) CurrentNamespace() string {
@@ -301,8 +298,7 @@ func (provider *Provider) CreateMizuRBAC(ctx context.Context, namespace string,
 }
 
 func (provider *Provider) RemoveNamespace(ctx context.Context, name string) error {
-	if isFound, err := provider.CheckNamespaceExists(ctx, name);
+	if isFound, err := provider.CheckNamespaceExists(ctx, name); err != nil {
-	err != nil {
 		return err
 	} else if !isFound {
 		return nil
@@ -324,8 +320,7 @@ func (provider *Provider) RemoveNonNamespacedResources(ctx context.Context, clus
 }
 
 func (provider *Provider) RemoveClusterRole(ctx context.Context, name string) error {
-	if isFound, err := provider.CheckClusterRoleExists(ctx, name);
+	if isFound, err := provider.CheckClusterRoleExists(ctx, name); err != nil {
-	err != nil {
 		return err
 	} else if !isFound {
 		return nil
@@ -335,8 +330,7 @@ func (provider *Provider) RemoveClusterRole(ctx context.Context, name string) er
 }
 
 func (provider *Provider) RemoveClusterRoleBinding(ctx context.Context, name string) error {
-	if isFound, err := provider.CheckClusterRoleBindingExists(ctx, name);
+	if isFound, err := provider.CheckClusterRoleBindingExists(ctx, name); err != nil {
-	err != nil {
 		return err
 	} else if !isFound {
 		return nil
@@ -615,6 +609,10 @@ func getClientSet(config *restclient.Config) *kubernetes.Clientset {
 }
 
 func loadKubernetesConfiguration(kubeConfigPath string) clientcmd.ClientConfig {
+	if kubeConfigPath == "" {
+		kubeConfigPath = os.Getenv("KUBECONFIG")
+	}
+
 	if kubeConfigPath == "" {
 		home := homedir.HomeDir()
 		kubeConfigPath = filepath.Join(home, ".kube", "config")