Add topology command

Author: Guillaume Lefranc

topology.go

@@ -6,6 +6,7 @@ import (
 	"log"
 
 	"github.com/go-sql-driver/mysql"
+	"github.com/spf13/cobra"
 	"github.com/tanji/mariadb-tools/dbhelper"
 )
 
@@ -14,6 +15,10 @@ type topologyError struct {
 	Msg  string
 }
 
+func init() {
+	rootCmd.AddCommand(topologyCmd)
+}
+
 func (e topologyError) Error() string {
 	return fmt.Sprintf("%v [#%v]", e.Msg, e.Code)
 }
@@ -148,3 +153,25 @@ func printTopology() {
 		logprintf("DEBUG: Server [%d] %s %s", k, v.URL, v.State)
 	}
 }
+
+var topologyCmd = &cobra.Command{
+	Use:   "topology",
+	Short: "Print replication topology",
+	Long:  `Print the replication topology by detecting master and slaves`,
+	Run: func(cmd *cobra.Command, args []string) {
+		repmgrFlagCheck()
+		err := topologyInit()
+		if err != nil {
+			log.Fatalln(err)
+		}
+		for _, v := range servers {
+			fmt.Println(v.URL, v.State)
+		}
+	},
+	PostRun: func(cmd *cobra.Command, args []string) {
+		// Close connections on exit.
+		for _, server := range servers {
+			defer server.Conn.Close()
+		}
+	},
+}