Basic support for kubectl plugins

pkg/kubectl/cmd/plugin.go

@@ -0,0 +1,54 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+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 cmd
+
+import (
+	"io"
+	"os"
+
+	"github.com/spf13/cobra"
+	"k8s.io/kubernetes/pkg/kubectl/cmd/templates"
+	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
+	"k8s.io/kubernetes/pkg/kubectl/plugins"
+)
+
+// NewCmdForPlugin creates a command capable of running the provided plugin.
+func NewCmdForPlugin(plugin *plugins.Plugin, runner plugins.PluginRunner, in io.Reader, out, errout io.Writer) *cobra.Command {
+	if !plugin.IsValid() {
+		return nil
+	}
+
+	return &cobra.Command{
+		Use:     plugin.Name,
+		Short:   plugin.ShortDesc,
+		Long:    templates.LongDesc(plugin.LongDesc),
+		Example: templates.Examples(plugin.Example),
+		Run: func(cmd *cobra.Command, args []string) {
+			ctx := plugins.RunningContext{
+				In:         in,
+				Out:        out,
+				ErrOut:     errout,
+				Args:       args,
+				Env:        os.Environ(),
+				WorkingDir: plugin.Dir,
+			}
+			if err := runner.Run(plugin, ctx); err != nil {
+				cmdutil.CheckErr(err)
+			}
+		},
+	}
+}