add kubectl config

pkg/kubectl/cmd/config/use_context.go

@@ -0,0 +1,98 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package config
+
+import (
+	"errors"
+	"fmt"
+	"io"
+
+	"github.com/spf13/cobra"
+
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/client/clientcmd"
+)
+
+type useContextOptions struct {
+	pathOptions *pathOptions
+	contextName string
+}
+
+func NewCmdConfigUseContext(out io.Writer, pathOptions *pathOptions) *cobra.Command {
+	options := &useContextOptions{pathOptions: pathOptions}
+
+	cmd := &cobra.Command{
+		Use:   "use-context context-name",
+		Short: "Sets the current-context in a .kubeconfig file",
+		Long:  `Sets the current-context in a .kubeconfig file`,
+		Run: func(cmd *cobra.Command, args []string) {
+			if !options.complete(cmd) {
+				return
+			}
+
+			err := options.run()
+			if err != nil {
+				fmt.Printf("%v\n", err)
+			}
+		},
+	}
+
+	return cmd
+}
+
+func (o useContextOptions) run() error {
+	err := o.validate()
+	if err != nil {
+		return err
+	}
+
+	config, filename, err := o.pathOptions.getStartingConfig()
+	if err != nil {
+		return err
+	}
+
+	if len(filename) == 0 {
+		return errors.New("cannot set current-context without using a specific file")
+	}
+
+	config.CurrentContext = o.contextName
+
+	err = clientcmd.WriteToFile(*config, filename)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (o *useContextOptions) complete(cmd *cobra.Command) bool {
+	endingArgs := cmd.Flags().Args()
+	if len(endingArgs) != 1 {
+		cmd.Help()
+		return false
+	}
+
+	o.contextName = endingArgs[0]
+	return true
+}
+
+func (o useContextOptions) validate() error {
+	if len(o.contextName) == 0 {
+		return errors.New("You must specify a current-context")
+	}
+
+	return nil
+}