Merge pull request #289 from pdettori/issue-288

✨ more forceful kflex ctx commands

cmd/kflex/create/create.go

@@ -38,12 +38,12 @@ type CPCreate struct {
 	common.CP
 }
 
-// Create a ne control plane
+// Create a new control plane
 func (c *CPCreate) Create(controlPlaneType, backendType, hook string, hookVars []string, chattyStatus bool) {
 	done := make(chan bool)
 	var wg sync.WaitGroup
 	cx := cont.CPCtx{}
-	cx.Context(chattyStatus, false)
+	cx.Context(chattyStatus, false, false, false)
 
 	clp, err := kfclient.GetClient(c.Kubeconfig)
 	if err != nil {

cmd/kflex/ctx/ctx.go

@@ -40,7 +40,7 @@ type CPCtx struct {
 }
 
 // Context switch context in Kubeconfig
-func (c *CPCtx) Context(chattyStatus, failIfNone bool) {
+func (c *CPCtx) Context(chattyStatus, failIfNone, overwriteExistingCtx, setCurrentCtxAsHosting bool) {
 	done := make(chan bool)
 	var wg sync.WaitGroup
 	kconf, err := kubeconfig.LoadKubeconfig(c.Ctx)
@@ -51,6 +51,9 @@ func (c *CPCtx) Context(chattyStatus, failIfNone bool) {
 
 	switch c.CP.Name {
 	case "":
+		if setCurrentCtxAsHosting { // set hosting cluster context unconditionally to the current context
+			kubeconfig.SetHostingClusterContextPreference(kconf, nil)
+		}
 		util.PrintStatus("Checking for saved hosting cluster context...", done, &wg, chattyStatus)
 		time.Sleep(1 * time.Second)
 		done <- true
@@ -64,19 +67,32 @@ func (c *CPCtx) Context(chattyStatus, failIfNone bool) {
 		} else if failIfNone {
 			if !c.isCurrentContextHostingClusterContext() {
 				fmt.Fprintln(os.Stderr, "The hosting cluster context is not known!\n"+
-					"You can make it known to kflex by doing `kubectl config use-context $name_of_hosting_context` "+
-					"and then either `kflex ctx` or `kflex create ...`")
+					"You can make it known to kflex by doing `kubectl config use-context` \n"+
+					"to set the current context to the hosting cluster context and then using \n"+
+					"`kflex ctx --set-current-for-hosting` to restore the needed kubeconfig extension.")
 				os.Exit(1)
 			}
 			util.PrintStatus("Hosting cluster context not set, setting it to current context", done, &wg, chattyStatus)
-			kubeconfig.SetHostingClusterContextPreference(kconf)
+			kubeconfig.SetHostingClusterContextPreference(kconf, nil)
 			done <- true
 		}
 	default:
 		ctxName := certs.GenerateContextName(c.Name)
+		if overwriteExistingCtx {
+			util.PrintStatus("Overwriting existing context for control plane", done, &wg, chattyStatus)
+			if err = kubeconfig.DeleteContext(kconf, c.Name); err != nil {
+				fmt.Fprintf(os.Stderr, "no kubeconfig context for %s was found: %s\n", c.Name, err)
+			}
+			done <- true
+		}
+
 		util.PrintStatus(fmt.Sprintf("Switching to context %s...", ctxName), done, &wg, chattyStatus)
 		if err = kubeconfig.SwitchContext(kconf, c.Name); err != nil {
-			fmt.Fprintf(os.Stderr, "kubeconfig context %s not found (%s), trying to load from server...\n", c.Name, err)
+			if overwriteExistingCtx {
+				fmt.Fprintf(os.Stderr, "trying to load new context %s from server...\n", c.Name)
+			} else {
+				fmt.Fprintf(os.Stderr, "kubeconfig context %s not found (%s), trying to load from server...\n", c.Name, err)
+			}
 			if err := c.switchToHostingClusterContextAndWrite(kconf); err != nil {
 				fmt.Fprintf(os.Stderr, "Error switching back to hosting cluster context: %s\n", err)
 				os.Exit(1)
@@ -97,6 +113,7 @@ func (c *CPCtx) Context(chattyStatus, failIfNone bool) {
 			}
 		}
 		done <- true
+
 	}
 
 	if err = kubeconfig.WriteKubeconfig(c.Ctx, kconf); err != nil {

cmd/kflex/delete/delete.go

@@ -50,7 +50,8 @@ func (c *CPDelete) Delete(chattyStatus bool) {
 	}
 
 	if err = kubeconfig.SwitchToHostingClusterContext(kconf, false); err != nil {
-		fmt.Fprintf(os.Stderr, "no initial kubeconfig context was found: %s\n", err)
+		fmt.Fprintf(os.Stderr, "error switching to hosting cluster kubeconfig context: %s\n", err)
+		os.Exit(1)
 	}
 
 	if err = kubeconfig.DeleteContext(kconf, c.Name); err != nil {

cmd/kflex/main.go

@@ -51,6 +51,8 @@ var externalPort int
 var chattyStatus bool
 var hookVars []string
 var hostContainer string
+var overwriteExistingCtx bool
+var setCurrentCtxAsHosting bool
 
 // defaults
 const BKTypeDefault = string(tenancyv1alpha1.BackendDBTypeShared)
@@ -175,7 +177,7 @@ var ctxCmd = &cobra.Command{
 				Kubeconfig: kubeconfig,
 			},
 		}
-		cp.Context(chattyStatus, true)
+		cp.Context(chattyStatus, true, overwriteExistingCtx, setCurrentCtxAsHosting)
 	},
 }
 
@@ -206,6 +208,8 @@ func init() {
 	ctxCmd.Flags().StringVarP(&kubeconfig, "kubeconfig", "k", "", "path to kubeconfig file")
 	ctxCmd.Flags().IntVarP(&verbosity, "verbosity", "v", 0, "log level") // TODO - figure out how to inject verbosity
 	ctxCmd.Flags().BoolVarP(&chattyStatus, "chatty-status", "s", true, "chatty status indicator")
+	ctxCmd.Flags().BoolVarP(&overwriteExistingCtx, "overwrite-existing-context", "o", false, "Overwrite of hosting cluster context with new control plane context")
+	ctxCmd.Flags().BoolVarP(&setCurrentCtxAsHosting, "set-current-for-hosting", "c", false, "Set current context as hosting cluster context")
 
 	rootCmd.AddCommand(versionCmd)
 	rootCmd.AddCommand(initCmd)

docs/users.md

@@ -187,6 +187,15 @@ kflex ctx
 
 That command requires your kubeconfig file to hold an extension that `kflex init` created to hold the name of the hosting cluster context. See [below](#hosting-context) for more information.
 
+To update or refresh outdated or corrupted context information for a control plane stored in 
+the kubeconfig file, you can forcefully reload and overwrite the existing context data from 
+the KubeFlex hosting cluster. This can be accomplished by using the `--overwrite-existing-context` 
+flag. Here is an example:
+
+```shell
+kflex ctx cp1 --overwrite-existing-context
+```
+
 To switch back to a control plane context, use the
 `ctx <control plane name>` command, e.g:
 
@@ -718,9 +727,8 @@ You can do this in either of the two following ways.
 
 If the relevant extension is missing then you can restore it by using
 `kubectl config use-context` to set the current context to the hosting
-cluster context and then using `kflex ctx $cpname` to switch to
-another context. In the course of doing that, `kflex` will restore the
-needed kubeconfig extension.
+cluster context and then using `kflex ctx --set-current-for-hosting` 
+to restore the needed kubeconfig extension.
 
 ### Restore Hosting Context Preference by editing kubeconfig file
 

pkg/kubeconfig/config-util.go

@@ -48,7 +48,7 @@ func merge(existing, new *clientcmdapi.Config) error {
 	}
 
 	if !IsHostingClusterContextPreferenceSet(existing) {
-		SetHostingClusterContextPreference(existing)
+		SetHostingClusterContextPreference(existing, nil)
 	}
 
 	// set the current context to the nex context
@@ -88,6 +88,7 @@ func SwitchToHostingClusterContext(config *clientcmdapi.Config, removeExtension
 	if !IsHostingClusterContextPreferenceSet(config) {
 		return fmt.Errorf("hosting cluster preference context not set")
 	}
+
 	// found that the only way to unmarshal the runtime.Object into a ConfigMap
 	// was to use the unMarshallCM() function based on json marshal/unmarshal
 	cm, err := unMarshallCM(config.Preferences.Extensions[ConfigExtensionName])
@@ -99,6 +100,13 @@ func SwitchToHostingClusterContext(config *clientcmdapi.Config, removeExtension
 	if !ok {
 		return fmt.Errorf("hosting cluster preference context data not set")
 	}
+
+	// make sure that context set in extension is a valid context
+	_, ok = config.Contexts[contextData]
+	if !ok {
+		return fmt.Errorf("hosting cluster preference context data is set to a non-existing context")
+	}
+
 	config.CurrentContext = contextData
 
 	// remove the extensions
@@ -108,14 +116,19 @@ func SwitchToHostingClusterContext(config *clientcmdapi.Config, removeExtension
 	return nil
 }
 
-func SetHostingClusterContextPreference(config *clientcmdapi.Config) {
+// sets hosting cluster context to current context if userSuppliedContext is nil, otherwise set to userSuppliedContext
+func SetHostingClusterContextPreference(config *clientcmdapi.Config, userSuppliedContext *string) {
+	hostingContext := config.CurrentContext
+	if userSuppliedContext != nil {
+		hostingContext = *userSuppliedContext
+	}
 	runtimeObjects := make(map[string]runtime.Object)
 	runtimeObjects[ConfigExtensionName] = &corev1.ConfigMap{
 		ObjectMeta: metav1.ObjectMeta{
 			Name: ConfigExtensionName,
 		},
 		Data: map[string]string{
-			InitialContextName: config.CurrentContext,
+			InitialContextName: hostingContext,
 		},
 	}
 
@@ -139,7 +152,7 @@ func SaveHostingClusterContextPreference(ctx context.Context) error {
 	if err != nil {
 		return fmt.Errorf("setHostingClusterContextPreference: error loading kubeconfig %s", err)
 	}
-	SetHostingClusterContextPreference(kconfig)
+	SetHostingClusterContextPreference(kconfig, nil)
 	return WriteKubeconfig(ctx, kconfig)
 }