headlamp: Add rename feature for stateless cluster

Signed-off-by: Kautilya Tripathi <[email protected]>
headlamp-k8s · Jul 22, 2024 · 294f7f2 · 294f7f2
1 parent c1d663e
commit 294f7f2
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Showing 17 changed files with 436 additions and 138 deletions.
diff --git a/backend/cmd/cluster.go b/backend/cmd/cluster.go
@@ -33,4 +33,5 @@ type KubeconfigRequest struct {
 type RenameClusterRequest struct {
 	NewClusterName string `json:"newClusterName"`
 	Source         string `json:"source"`
+	Stateless      bool   `json:"stateless"`
 }
diff --git a/backend/cmd/headlamp.go b/backend/cmd/headlamp.go
@@ -1067,6 +1067,60 @@ func (c *HeadlampConfig) getClusters() []Cluster {
 	return clusters
 }
 
+// parseCustomNameClusters parses the custom name clusters from the kubeconfig.
+func parseCustomNameClusters(contexts []kubeconfig.Context) ([]Cluster, []error) {
+	clusters := []Cluster{}
+
+	var setupErrors []error
+
+	for _, context := range contexts {
+		context := context
+
+		info := context.KubeContext.Extensions["headlamp_info"]
+		if info != nil {
+			// Convert the runtime.Unknown object to a byte slice
+			unknownBytes, err := json.Marshal(info)
+			if err != nil {
+				logger.Log(logger.LevelError, map[string]string{"cluster": context.Name},
+					err, "unmarshaling context data")
+
+				setupErrors = append(setupErrors, err)
+
+				continue
+			}
+
+			// Now, decode the byte slice into CustomObject
+			var customObj kubeconfig.CustomObject
+
+			err = json.Unmarshal(unknownBytes, &customObj)
+			if err != nil {
+				logger.Log(logger.LevelError, map[string]string{"cluster": context.Name},
+					err, "unmarshaling into CustomObject")
+
+				setupErrors = append(setupErrors, err)
+
+				continue
+			}
+
+			// Check if the CustomName field is present
+			if customObj.CustomName != "" {
+				context.Name = customObj.CustomName
+			}
+		}
+
+		clusters = append(clusters, Cluster{
+			Name:     context.Name,
+			Server:   context.Cluster.Server,
+			AuthType: context.AuthType(),
+			Metadata: map[string]interface{}{
+				"source": "dynamic_cluster",
+			},
+		})
+	}
+
+	return clusters, setupErrors
+}
+
 // parseClusterFromKubeConfig parses the kubeconfig and returns a list of contexts and errors.
 func parseClusterFromKubeConfig(kubeConfigs []string) ([]Cluster, []error) {
 	clusters := []Cluster{}
@@ -1100,17 +1154,7 @@ func parseClusterFromKubeConfig(kubeConfigs []string) ([]Cluster, []error) {
 			continue
 		}
 
-		for _, context := range contexts {
-			context := context
-			clusters = append(clusters, Cluster{
-				Name:     context.Name,
-				Server:   context.Cluster.Server,
-				AuthType: context.AuthType(),
-				Metadata: map[string]interface{}{
-					"source": "dynamic_cluster",
-				},
-			})
-		}
+		clusters, setupErrors = parseCustomNameClusters(contexts)
 	}
 
 	if len(setupErrors) > 0 {
@@ -1300,133 +1344,164 @@ func (c *HeadlampConfig) getKubeConfigPath(source string) (string, error) {
 	return defaultKubeConfigPersistenceFile()
 }
 
-// Handler for renaming a cluster.
-//
-//nolint:funlen
-func (c *HeadlampConfig) renameCluster(w http.ResponseWriter, r *http.Request) {
-	vars := mux.Vars(r)
-	clusterName := vars["name"]
-	// Parse request body
-	var reqBody RenameClusterRequest
-	if err := json.NewDecoder(r.Body).Decode(&reqBody); err != nil {
+// Handler for renaming a stateless cluster.
+func (c *HeadlampConfig) handleStatelessClusterRename(w http.ResponseWriter, r *http.Request, clusterName string) {
+	if err := c.kubeConfigStore.RemoveContext(clusterName); err != nil {
 		logger.Log(logger.LevelError, map[string]string{"cluster": clusterName},
 			err, "decoding request body")
 		http.Error(w, err.Error(), http.StatusBadRequest)
 
 		return
 	}
 
-	// Get path of kubeconfig from source
-	path, err := c.getKubeConfigPath(reqBody.Source)
-	if err != nil {
-		logger.Log(logger.LevelError, map[string]string{"cluster": clusterName},
-			err, "getting kubeconfig file")
-		http.Error(w, "getting kubeconfig file", http.StatusInternalServerError)
-
-		return
-	}
-
-	// Load kubeconfig file
-	config, err := clientcmd.LoadFromFile(path)
-	if err != nil {
-		logger.Log(logger.LevelError, map[string]string{"cluster": clusterName},
-			err, "loading kubeconfig file")
-		http.Error(w, "loading kubeconfig file", http.StatusInternalServerError)
-
-		return
-	}
-
-	// Find the context with the given cluster name
-	contextName := clusterName
-
-	// Iterate over the contexts to find the context with the given cluster name
-	for k, v := range config.Contexts {
-		info := v.Extensions["headlamp_info"]
-		if info != nil {
-			// Convert the runtime.Unknown object to a byte slice
-			unknownBytes, err := json.Marshal(info)
-			if err != nil {
-				logger.Log(logger.LevelError, map[string]string{"cluster": contextName},
-					err, "unmarshaling context data")
-				http.Error(w, "unmarshaling context data", http.StatusInternalServerError)
-
-				return
-			}
-
-			// Now, decode the byte slice into CustomObject
-			var customObj kubeconfig.CustomObject
-
-			err = json.Unmarshal(unknownBytes, &customObj)
-			if err != nil {
-				logger.Log(logger.LevelError, map[string]string{"cluster": contextName},
-					err, "unmarshaling into CustomObject")
-				http.Error(w, "unmarshaling into CustomObject", http.StatusInternalServerError)
-
-				return
-			}
+	w.WriteHeader(http.StatusCreated)
+	c.getConfig(w, r)
+}
 
-			// Check if the CustomName field matches the cluster name
-			if customObj.CustomName != "" && customObj.CustomName == clusterName {
-				contextName = k
-			}
-		}
-	}
+// customNameToExtenstions writes the custom name to the Extensions map in the kubeconfig.
+func customNameToExtenstions(config *api.Config, contextName, newClusterName, path string) error {
+	var err error
 
 	// Get the context with the given cluster name
 	contextConfig, ok := config.Contexts[contextName]
 	if !ok {
-		logger.Log(logger.LevelError, map[string]string{"cluster": clusterName},
+		logger.Log(logger.LevelError, map[string]string{"cluster": contextName},
 			err, "getting context from kubeconfig")
-		http.Error(w, "getting context from kubeconfig", http.StatusInternalServerError)
 
-		return
+		return err
 	}
 
 	// Create a CustomObject with CustomName field
 	customObj := &kubeconfig.CustomObject{
 		TypeMeta:   v1.TypeMeta{},
 		ObjectMeta: v1.ObjectMeta{},
-		CustomName: reqBody.NewClusterName,
+		CustomName: newClusterName,
 	}
 
 	// Assign the CustomObject to the Extensions map
 	contextConfig.Extensions["headlamp_info"] = customObj
 
 	if err := clientcmd.WriteToFile(*config, path); err != nil {
-		logger.Log(logger.LevelError, map[string]string{"cluster": clusterName},
+		logger.Log(logger.LevelError, map[string]string{"cluster": contextName},
 			err, "writing kubeconfig file")
-		http.Error(w, "writing kubeconfig file", http.StatusInternalServerError)
 
-		return
+		return err
 	}
 
+	return nil
+}
+
+// updateCustomContextToCache updates the custom context to the cache.
+func (c *HeadlampConfig) updateCustomContextToCache(config *api.Config, clusterName string) []error {
 	contexts, errs := kubeconfig.LoadContextsFromAPIConfig(config, false)
 	if len(contexts) == 0 {
-		logger.Log(logger.LevelError, nil, errors.New("no contexts found in kubeconfig"),
-			"getting contexts from kubeconfig")
-		http.Error(w, "getting contexts from kubeconfig", http.StatusBadRequest)
+		logger.Log(logger.LevelError, nil, errs, "no contexts found in kubeconfig")
+		errs = append(errs, errors.New("no contexts found in kubeconfig"))
 
-		return
+		return errs
 	}
 
 	for _, context := range contexts {
 		context := context
 
 		// Remove the old context from the store
 		if err := c.kubeConfigStore.RemoveContext(clusterName); err != nil {
+			logger.Log(logger.LevelError, nil, err, "Removing context from the store")
 			errs = append(errs, err)
 		}
 
 		// Add the new context to the store
-		if err = c.kubeConfigStore.AddContext(&context); err != nil {
+		if err := c.kubeConfigStore.AddContext(&context); err != nil {
+			logger.Log(logger.LevelError, nil, err, "Adding context to the store")
 			errs = append(errs, err)
 		}
 	}
 
 	if len(errs) > 0 {
-		logger.Log(logger.LevelError, nil, errs, "setting up contexts from kubeconfig")
-		http.Error(w, "setting up contexts from kubeconfig", http.StatusBadRequest)
+		return errs
+	}
+
+	return nil
+}
+
+// getPathAndLoadKubeconfig gets the path of the kubeconfig file and loads it.
+func (c *HeadlampConfig) getPathAndLoadKubeconfig(source, clusterName string) (string, *api.Config, error) {
+	// Get path of kubeconfig from source
+	path, err := c.getKubeConfigPath(source)
+	if err != nil {
+		logger.Log(logger.LevelError, map[string]string{"cluster": clusterName},
+			err, "getting kubeconfig file")
+
+		return "", nil, err
+	}
+
+	// Load kubeconfig file
+	config, err := clientcmd.LoadFromFile(path)
+	if err != nil {
+		logger.Log(logger.LevelError, map[string]string{"cluster": clusterName},
+			err, "loading kubeconfig file")
+
+		return "", nil, err
+	}
+
+	return path, config, nil
+}
 
+// Handler for renaming a cluster.
+func (c *HeadlampConfig) renameCluster(w http.ResponseWriter, r *http.Request) {
+	vars := mux.Vars(r)
+	clusterName := vars["name"]
+	// Parse request body.
+	var reqBody RenameClusterRequest
+	if err := json.NewDecoder(r.Body).Decode(&reqBody); err != nil {
+		logger.Log(logger.LevelError, map[string]string{"cluster": clusterName},
+			err, "decoding request body")
+		http.Error(w, err.Error(), http.StatusBadRequest)
+
+		return
+	}
+
+	if reqBody.Stateless {
+		// For stateless clusters we just need to remove cluster from cache
+		c.handleStatelessClusterRename(w, r, clusterName)
+	}
+
+	// Get path of kubeconfig from source
+	path, config, err := c.getPathAndLoadKubeconfig(reqBody.Source, clusterName)
+	if err != nil {
+		http.Error(w, "getting kubeconfig file", http.StatusInternalServerError)
+		return
+	}
+
+	// Find the context with the given cluster name
+	contextName := clusterName
+
+	// Iterate over the contexts to find the context with the given cluster name
+	for k, v := range config.Contexts {
+		info := v.Extensions["headlamp_info"]
+		if info != nil {
+			customObj, err := MarshalCustomObject(info, contextName)
+			if err != nil {
+				logger.Log(logger.LevelError, map[string]string{"cluster": contextName},
+					err, "marshaling custom object")
+
+				return
+			}
+
+			// Check if the CustomName field matches the cluster name
+			if customObj.CustomName != "" && customObj.CustomName == clusterName {
+				contextName = k
+			}
+		}
+	}
+
+	if err := customNameToExtenstions(config, contextName, reqBody.NewClusterName, path); err != nil {
+		http.Error(w, "writing custom extension to kubeconfig", http.StatusInternalServerError)
+		return
+	}
+
+	if errs := c.updateCustomContextToCache(config, clusterName); len(errs) > 0 {
+		http.Error(w, "setting up contexts from kubeconfig", http.StatusBadRequest)
 		return
 	}