Reparent: Move TER vtctl command from vttablet to wrangler

go/vt/vtctl/reparent.go

@@ -52,6 +52,12 @@ func init() {
 		commandEmergencyReparentShard,
 		"-keyspace_shard=<keyspace/shard> -new_master=<tablet alias>",
 		"Reparents the shard to the new master. Assumes the old master is dead and not responsding."})
+	addCommand("Shards", command{
+		"TabletExternallyReparented",
+		commandTabletExternallyReparented,
+		"<tablet alias>",
+		"Changes metadata in the topology server to acknowledge a shard master change performed by an external tool. See the Reparenting guide for more information:" +
+			"https://vitess.io/docs/user-guides/reparenting/#external-reparenting"})
 }
 
 func commandReparentTablet(ctx context.Context, wr *wrangler.Wrangler, subFlags *flag.FlagSet, args []string) error {
@@ -171,3 +177,18 @@ func commandEmergencyReparentShard(ctx context.Context, wr *wrangler.Wrangler, s
 	}
 	return wr.EmergencyReparentShard(ctx, keyspace, shard, tabletAlias, *waitSlaveTimeout)
 }
+
+func commandTabletExternallyReparented(ctx context.Context, wr *wrangler.Wrangler, subFlags *flag.FlagSet, args []string) error {
+	if err := subFlags.Parse(args); err != nil {
+		return err
+	}
+	if subFlags.NArg() != 1 {
+		return fmt.Errorf("action TabletExternallyReparented requires <tablet alias>")
+	}
+
+	tabletAlias, err := topoproto.ParseTabletAlias(subFlags.Arg(0))
+	if err != nil {
+		return err
+	}
+	return wr.TabletExternallyReparented(ctx, tabletAlias)
+}

go/vt/vtctl/vtctl.go

@@ -228,10 +228,6 @@ var commands = []commandGroup{
 			{"GetShard", commandGetShard,
 				"<keyspace/shard>",
 				"Outputs a JSON structure that contains information about the Shard."},
-			{"TabletExternallyReparented", commandTabletExternallyReparented,
-				"<tablet alias>",
-				"Changes metadata in the topology server to acknowledge a shard master change performed by an external tool. See the Reparenting guide for more information:" +
-					"https://github.com/vitessio/vitess/blob/master/doc/Reparenting.md#external-reparents."},
 			{"ValidateShard", commandValidateShard,
 				"[-ping-tablets] <keyspace/shard>",
 				"Validates that all nodes that are reachable from this shard are consistent."},
@@ -1203,25 +1199,6 @@ func commandGetShard(ctx context.Context, wr *wrangler.Wrangler, subFlags *flag.
 	return printJSON(wr.Logger(), shardInfo.Shard)
 }
 
-func commandTabletExternallyReparented(ctx context.Context, wr *wrangler.Wrangler, subFlags *flag.FlagSet, args []string) error {
-	if err := subFlags.Parse(args); err != nil {
-		return err
-	}
-	if subFlags.NArg() != 1 {
-		return fmt.Errorf("the <tablet alias> argument is required for the TabletExternallyReparented command")
-	}
-
-	tabletAlias, err := topoproto.ParseTabletAlias(subFlags.Arg(0))
-	if err != nil {
-		return err
-	}
-	ti, err := wr.TopoServer().GetTablet(ctx, tabletAlias)
-	if err != nil {
-		return err
-	}
-	return wr.TabletManagerClient().TabletExternallyReparented(ctx, ti.Tablet, "")
-}
-
 func commandValidateShard(ctx context.Context, wr *wrangler.Wrangler, subFlags *flag.FlagSet, args []string) error {
 	pingTablets := subFlags.Bool("ping-tablets", true, "Indicates whether all tablets should be pinged during the validation process")
 	if err := subFlags.Parse(args); err != nil {

go/vt/wrangler/reparent.go

@@ -41,9 +41,10 @@ import (
 )
 
 const (
-	initShardMasterOperation        = "InitShardMaster"
-	plannedReparentShardOperation   = "PlannedReparentShard"
-	emergencyReparentShardOperation = "EmergencyReparentShard"
+	initShardMasterOperation            = "InitShardMaster"
+	plannedReparentShardOperation       = "PlannedReparentShard"
+	emergencyReparentShardOperation     = "EmergencyReparentShard"
+	tabletExternallyReparentedOperation = "TabletExternallyReparented"
 )
 
 // ShardReplicationStatuses returns the ReplicationStatus for each tablet in a shard.
@@ -812,3 +813,51 @@ func (wr *Wrangler) emergencyReparentShardLocked(ctx context.Context, ev *events
 
 	return nil
 }
+
+// TabletExternallyReparented changes the type of new master for this shard to MASTER
+// and updates it's tablet record in the topo. Updating the shard record is handled
+// by the new master tablet
+func (wr *Wrangler) TabletExternallyReparented(ctx context.Context, newMasterAlias *topodatapb.TabletAlias) error {
+
+	tabletInfo, err := wr.ts.GetTablet(ctx, newMasterAlias)
+	if err != nil {
+		log.Warningf("TabletExternallyReparented: failed to read tablet record for %v: %v", newMasterAlias, err)
+		return err
+	}
+
+	// Check the global shard record.
+	tablet := tabletInfo.Tablet
+	si, err := wr.ts.GetShard(ctx, tablet.Keyspace, tablet.Shard)
+	if err != nil {
+		log.Warningf("TabletExternallyReparented: failed to read global shard record for %v/%v: %v", tablet.Keyspace, tablet.Shard, err)
+		return err
+	}
+
+	// We update the tablet only if it is not currently master
+	if tablet.Type != topodatapb.TabletType_MASTER {
+		log.Infof("TabletExternallyReparented: executing tablet type change to MASTER")
+
+		// Create a reusable Reparent event with available info.
+		ev := &events.Reparent{
+			ShardInfo: *si,
+			NewMaster: *tablet,
+			OldMaster: topodatapb.Tablet{
+				Alias: si.MasterAlias,
+				Type:  topodatapb.TabletType_MASTER,
+			},
+		}
+		defer func() {
+			if err != nil {
+				event.DispatchUpdate(ev, "failed: "+err.Error())
+			}
+		}()
+		event.DispatchUpdate(ev, "starting external reparent")
+
+		if err := wr.tmc.ChangeType(ctx, tablet, topodatapb.TabletType_MASTER); err != nil {
+			log.Warningf("Error calling ChangeType on new master %v: %v", topoproto.TabletAliasString(newMasterAlias), err)
+			return err
+		}
+		event.DispatchUpdate(ev, "finished")
+	}
+	return nil
+}

go/vt/wrangler/testlib/reparent_external_test.go → go/vt/wrangler/testlib/rpc_reparent_external_test.go

@@ -44,8 +44,6 @@ func TestTabletExternallyReparented(t *testing.T) {
 	ctx := context.Background()
 	ts := memorytopo.NewServer("cell1", "cell2")
 	wr := wrangler.New(logutil.NewConsoleLogger(), ts, tmclient.NewTabletManagerClient())
-	vp := NewVtctlPipe(t, ts)
-	defer vp.Close()
 
 	// Create an old master, a new master, two good slaves, one bad slave
 	oldMaster := NewFakeTablet(t, wr, "cell1", 0, topodatapb.TabletType_MASTER, nil)
@@ -127,7 +125,8 @@ func TestTabletExternallyReparented(t *testing.T) {
 	if err != nil {
 		t.Fatalf("GetTablet failed: %v", err)
 	}
-	if err := vp.Run([]string{"TabletExternallyReparented", topoproto.TabletAliasString(oldMaster.Tablet.Alias)}); err != nil {
+	waitID := makeWaitID()
+	if err := tmc.TabletExternallyReparented(context.Background(), oldMaster.Tablet, waitID); err != nil {
 		t.Fatalf("TabletExternallyReparented(same master) should have worked: %v", err)
 	}
 
@@ -140,7 +139,7 @@ func TestTabletExternallyReparented(t *testing.T) {
 	if err != nil {
 		t.Fatalf("GetTablet failed: %v", err)
 	}
-	waitID := makeWaitID()
+	waitID = makeWaitID()
 	if err := tmc.TabletExternallyReparented(context.Background(), ti.Tablet, waitID); err != nil {
 		t.Fatalf("TabletExternallyReparented(slave) error: %v", err)
 	}