Add cmd to list plugins (#1535)

* Add cmd to list plugins

Signed-off-by: Carlisia <carlisiac@vmware.com>

pkg/cmd/cli/plugin/get.go

@@ -0,0 +1,69 @@
+/*
+Copyright 2019 the Velero contributors.
+
+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 plugin
+
+import (
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/spf13/cobra"
+
+	"github.com/heptio/velero/pkg/client"
+	"github.com/heptio/velero/pkg/cmd"
+	"github.com/heptio/velero/pkg/cmd/cli/serverstatus"
+	"github.com/heptio/velero/pkg/cmd/util/output"
+)
+
+func NewGetCommand(f client.Factory, use string) *cobra.Command {
+	serverStatusGetter := &serverstatus.DefaultServerStatusGetter{
+		Timeout: 5 * time.Second,
+	}
+
+	c := &cobra.Command{
+		Use:   use,
+		Short: "Get information for all plugins on the velero server",
+		Run: func(c *cobra.Command, args []string) {
+			err := output.ValidateFlags(c)
+			cmd.CheckError(err)
+
+			serverStatusGetter := &serverstatus.DefaultServerStatusGetter{
+				Namespace: f.Namespace(),
+				Timeout:   5 * time.Second,
+			}
+
+			client, err := f.Client()
+			cmd.CheckError(err)
+
+			veleroClient := client.VeleroV1()
+
+			serverStatus, err := serverStatusGetter.GetServerStatus(veleroClient)
+			if err != nil {
+				fmt.Fprintf(os.Stdout, "<error getting plugin information: %s>\n", err)
+				return
+			}
+
+			_, err = output.PrintWithFormat(c, serverStatus)
+			cmd.CheckError(err)
+		},
+	}
+
+	c.Flags().DurationVar(&serverStatusGetter.Timeout, "timeout", serverStatusGetter.Timeout, "maximum time to wait for plugin information to be reported")
+	output.BindFlagsSimple(c.Flags())
+
+	return c
+}

pkg/cmd/cli/plugin/plugin.go

@@ -32,6 +32,7 @@ func NewCommand(f client.Factory) *cobra.Command {
 	c.AddCommand(
 		NewAddCommand(f),
 		NewRemoveCommand(f),
+		NewGetCommand(f, "get"),
 	)
 
 	return c