add node ls

cmd/kaf/node.go

@@ -0,0 +1,53 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"text/tabwriter"
+
+	"sort"
+
+	"github.com/spf13/cobra"
+)
+
+func init() {
+	rootCmd.AddCommand(nodeCommand)
+	nodeCommand.AddCommand(nodeLsCommand)
+	nodeLsCommand.Flags().BoolVar(&noHeaderFlag, "no-headers", false, "Hide table headers")
+}
+
+var nodeCommand = &cobra.Command{
+	Use:   "node",
+	Short: "Describe and List nodes",
+}
+
+var nodeLsCommand = &cobra.Command{
+	Use:   "ls",
+	Short: "List nodes in a cluster",
+	Run: func(cmd *cobra.Command, args []string) {
+		admin, err := getClusterAdmin()
+		if err != nil {
+			panic(err)
+		}
+
+		brokers, _, err := admin.DescribeCluster()
+		if err != nil {
+			panic(err)
+		}
+
+		sort.Slice(brokers, func(i, j int) bool {
+			return brokers[i].ID() < brokers[j].ID()
+		})
+
+		w := tabwriter.NewWriter(os.Stdout, tabwriterMinWidth, tabwriterWidth, tabwriterPadding, tabwriterPadChar, tabwriterFlags)
+		if !noHeaderFlag {
+			fmt.Fprintf(w, "ID\tADDRESS\t\n")
+		}
+
+		for _, broker := range brokers {
+			fmt.Fprintf(w, "%v\t%v\t\n", broker.ID(), broker.Addr())
+		}
+
+		w.Flush()
+	},
+}