Exemplo n.º 1
0
// updateShardCellsAndMaster will update the 'Cells' and possibly
// MasterAlias records for the shard, if needed.
func (wr *Wrangler) updateShardCellsAndMaster(ctx context.Context, si *topo.ShardInfo, tabletAlias *topodatapb.TabletAlias, tabletType topodatapb.TabletType, allowMasterOverride bool) error {
	// See if we need to update the Shard:
	// - add the tablet's cell to the shard's Cells if needed
	// - change the master if needed
	shardUpdateRequired := false
	if !si.HasCell(tabletAlias.Cell) {
		shardUpdateRequired = true
	}
	if tabletType == topodatapb.TabletType_MASTER && !topoproto.TabletAliasEqual(si.MasterAlias, tabletAlias) {
		shardUpdateRequired = true
	}
	if !shardUpdateRequired {
		return nil
	}

	actionNode := actionnode.UpdateShard()
	keyspace := si.Keyspace()
	shard := si.ShardName()
	lockPath, err := wr.lockShard(ctx, keyspace, shard, actionNode)
	if err != nil {
		return err
	}

	// re-read the shard with the lock
	si, err = wr.ts.GetShard(ctx, keyspace, shard)
	if err != nil {
		return wr.unlockShard(ctx, keyspace, shard, actionNode, lockPath, err)
	}

	// update it
	wasUpdated := false
	if !si.HasCell(tabletAlias.Cell) {
		si.Cells = append(si.Cells, tabletAlias.Cell)
		wasUpdated = true
	}
	if tabletType == topodatapb.TabletType_MASTER && !topoproto.TabletAliasEqual(si.MasterAlias, tabletAlias) {
		if si.HasMaster() && !allowMasterOverride {
			return wr.unlockShard(ctx, keyspace, shard, actionNode, lockPath, fmt.Errorf("creating this tablet would override old master %v in shard %v/%v", topoproto.TabletAliasString(si.MasterAlias), keyspace, shard))
		}
		si.MasterAlias = tabletAlias
		wasUpdated = true
	}

	if wasUpdated {
		// write it back
		if err := wr.ts.UpdateShard(ctx, si); err != nil {
			return wr.unlockShard(ctx, keyspace, shard, actionNode, lockPath, err)
		}
	}

	// and unlock
	return wr.unlockShard(ctx, keyspace, shard, actionNode, lockPath, err)
}
Exemplo n.º 2
0
// updateShardCellsAndMaster will update the 'Cells' and possibly
// MasterAlias records for the shard, if needed.
func (wr *Wrangler) updateShardCellsAndMaster(ctx context.Context, si *topo.ShardInfo, tabletAlias *topodatapb.TabletAlias, tabletType topodatapb.TabletType, allowMasterOverride bool) error {
	// See if we need to update the Shard:
	// - add the tablet's cell to the shard's Cells if needed
	// - change the master if needed
	shardUpdateRequired := false
	if !si.HasCell(tabletAlias.Cell) {
		shardUpdateRequired = true
	}
	if tabletType == topodatapb.TabletType_MASTER && !topoproto.TabletAliasEqual(si.MasterAlias, tabletAlias) {
		shardUpdateRequired = true
	}
	if !shardUpdateRequired {
		return nil
	}

	// we do need to update the shard, lock it to not interfere with
	// reparenting operations.
	actionNode := actionnode.UpdateShard()
	keyspace := si.Keyspace()
	shard := si.ShardName()
	lockPath, err := wr.lockShard(ctx, keyspace, shard, actionNode)
	if err != nil {
		return err
	}

	// run the update
	_, err = wr.ts.UpdateShardFields(ctx, keyspace, shard, func(s *topodatapb.Shard) error {
		wasUpdated := false
		if !topoproto.ShardHasCell(s, tabletAlias.Cell) {
			s.Cells = append(s.Cells, tabletAlias.Cell)
			wasUpdated = true
		}

		if tabletType == topodatapb.TabletType_MASTER && !topoproto.TabletAliasEqual(s.MasterAlias, tabletAlias) {
			if !topoproto.TabletAliasIsZero(s.MasterAlias) && !allowMasterOverride {
				return fmt.Errorf("creating this tablet would override old master %v in shard %v/%v", topoproto.TabletAliasString(s.MasterAlias), keyspace, shard)
			}
			s.MasterAlias = tabletAlias
			wasUpdated = true
		}

		if !wasUpdated {
			return topo.ErrNoUpdateNeeded
		}
		return nil
	})
	return wr.unlockShard(ctx, keyspace, shard, actionNode, lockPath, err)
}
Exemplo n.º 3
0
// Validate makes sure a tablet is represented correctly in the topology server.
func Validate(ctx context.Context, ts Server, tabletAlias *topodatapb.TabletAlias) error {
	// read the tablet record, make sure it parses
	tablet, err := ts.GetTablet(ctx, tabletAlias)
	if err != nil {
		return err
	}
	if !topoproto.TabletAliasEqual(tablet.Alias, tabletAlias) {
		return fmt.Errorf("bad tablet alias data for tablet %v: %#v", topoproto.TabletAliasString(tabletAlias), tablet.Alias)
	}

	// Validate the entry in the shard replication nodes
	if err = ts.ValidateShard(ctx, tablet.Keyspace, tablet.Shard); err != nil {
		return err
	}

	si, err := ts.GetShardReplication(ctx, tablet.Alias.Cell, tablet.Keyspace, tablet.Shard)
	if err != nil {
		return err
	}

	if _, err = si.GetShardReplicationNode(tabletAlias); err != nil {
		return fmt.Errorf("tablet %v not found in cell %v shard replication: %v", tabletAlias, tablet.Alias.Cell, err)
	}

	return nil
}
Exemplo n.º 4
0
// remove takes in an array and returns it with the specified element removed
// (leaves the array unchanged if element isn't in the array).
func remove(tablets []*discovery.TabletStats, tabletAlias *topodata.TabletAlias) []*discovery.TabletStats {
	filteredTablets := tablets[:0]
	for _, tablet := range tablets {
		if !topoproto.TabletAliasEqual(tablet.Tablet.Alias, tabletAlias) {
			filteredTablets = append(filteredTablets, tablet)
		}
	}
	return filteredTablets
}
Exemplo n.º 5
0
// ValidatePermissionsKeyspace validates all the permissions are the same
// in a keyspace
func (wr *Wrangler) ValidatePermissionsKeyspace(ctx context.Context, keyspace string) error {
	// find all the shards
	shards, err := wr.ts.GetShardNames(ctx, keyspace)
	if err != nil {
		return err
	}

	// corner cases
	if len(shards) == 0 {
		return fmt.Errorf("No shards in keyspace %v", keyspace)
	}
	sort.Strings(shards)
	if len(shards) == 1 {
		return wr.ValidatePermissionsShard(ctx, keyspace, shards[0])
	}

	// find the reference permissions using the first shard's master
	si, err := wr.ts.GetShard(ctx, keyspace, shards[0])
	if err != nil {
		return err
	}
	if !si.HasMaster() {
		return fmt.Errorf("No master in shard %v/%v", keyspace, shards[0])
	}
	referenceAlias := si.MasterAlias
	log.Infof("Gathering permissions for reference master %v", topoproto.TabletAliasString(referenceAlias))
	referencePermissions, err := wr.GetPermissions(ctx, si.MasterAlias)
	if err != nil {
		return err
	}

	// then diff with all tablets but master 0
	er := concurrency.AllErrorRecorder{}
	wg := sync.WaitGroup{}
	for _, shard := range shards {
		aliases, err := wr.ts.FindAllTabletAliasesInShard(ctx, keyspace, shard)
		if err != nil {
			er.RecordError(err)
			continue
		}

		for _, alias := range aliases {
			if topoproto.TabletAliasEqual(alias, si.MasterAlias) {
				continue
			}

			wg.Add(1)
			go wr.diffPermissions(ctx, referencePermissions, referenceAlias, alias, &wg, &er)
		}
	}
	wg.Wait()
	if er.HasErrors() {
		return fmt.Errorf("Permissions diffs:\n%v", er.Error().Error())
	}
	return nil
}
Exemplo n.º 6
0
// InitTablet creates or updates a tablet. If no parent is specified
// in the tablet, and the tablet has a slave type, we will find the
// appropriate parent. If createShardAndKeyspace is true and the
// parent keyspace or shard don't exist, they will be created.  If
// allowUpdate is true, and a tablet with the same ID exists, just update it.
// If a tablet is created as master, and there is already a different
// master in the shard, allowMasterOverride must be set.
func (wr *Wrangler) InitTablet(ctx context.Context, tablet *topodatapb.Tablet, allowMasterOverride, createShardAndKeyspace, allowUpdate bool) error {
	if err := topo.TabletComplete(tablet); err != nil {
		return err
	}

	// get the shard, possibly creating it
	var err error
	var si *topo.ShardInfo

	if createShardAndKeyspace {
		// create the parent keyspace and shard if needed
		si, err = wr.ts.GetOrCreateShard(ctx, tablet.Keyspace, tablet.Shard)
	} else {
		si, err = wr.ts.GetShard(ctx, tablet.Keyspace, tablet.Shard)
		if err == topo.ErrNoNode {
			return fmt.Errorf("missing parent shard, use -parent option to create it, or CreateKeyspace / CreateShard")
		}
	}

	// get the shard, checks a couple things
	if err != nil {
		return fmt.Errorf("cannot get (or create) shard %v/%v: %v", tablet.Keyspace, tablet.Shard, err)
	}
	if !key.KeyRangeEqual(si.KeyRange, tablet.KeyRange) {
		return fmt.Errorf("shard %v/%v has a different KeyRange: %v != %v", tablet.Keyspace, tablet.Shard, si.KeyRange, tablet.KeyRange)
	}
	if tablet.Type == topodatapb.TabletType_MASTER && si.HasMaster() && !topoproto.TabletAliasEqual(si.MasterAlias, tablet.Alias) && !allowMasterOverride {
		return fmt.Errorf("creating this tablet would override old master %v in shard %v/%v, use allow_master_override flag", topoproto.TabletAliasString(si.MasterAlias), tablet.Keyspace, tablet.Shard)
	}

	// update the shard record if needed
	if err := wr.updateShardCellsAndMaster(ctx, si, tablet.Alias, tablet.Type, allowMasterOverride); err != nil {
		return err
	}

	err = wr.ts.CreateTablet(ctx, tablet)
	if err == topo.ErrNodeExists && allowUpdate {
		// Try to update then
		oldTablet, err := wr.ts.GetTablet(ctx, tablet.Alias)
		if err != nil {
			return fmt.Errorf("failed reading existing tablet %v: %v", topoproto.TabletAliasString(tablet.Alias), err)
		}

		// Check we have the same keyspace / shard, and if not,
		// require the allowDifferentShard flag.
		if oldTablet.Keyspace != tablet.Keyspace || oldTablet.Shard != tablet.Shard {
			return fmt.Errorf("old tablet has shard %v/%v. Cannot override with shard %v/%v. Delete and re-add tablet if you want to change the tablet's keyspace/shard", oldTablet.Keyspace, oldTablet.Shard, tablet.Keyspace, tablet.Shard)
		}

		*(oldTablet.Tablet) = *tablet
		if err := wr.ts.UpdateTablet(ctx, oldTablet); err != nil {
			return fmt.Errorf("failed updating tablet %v: %v", topoproto.TabletAliasString(tablet.Alias), err)
		}
	}
	return nil
}
Exemplo n.º 7
0
func (agent *ActionAgent) startReplication(ctx context.Context, pos replication.Position) error {
	// Set the position at which to resume from the master.
	cmds, err := agent.MysqlDaemon.SetSlavePositionCommands(pos)
	if err != nil {
		return err
	}
	if err := agent.MysqlDaemon.ExecuteSuperQueryList(ctx, cmds); err != nil {
		return fmt.Errorf("failed to set slave position: %v", err)
	}

	// Read the shard to find the current master, and its location.
	tablet := agent.Tablet()
	si, err := agent.TopoServer.GetShard(ctx, tablet.Keyspace, tablet.Shard)
	if err != nil {
		return fmt.Errorf("can't read shard: %v", err)
	}
	if si.MasterAlias == nil {
		// We've restored, but there's no master. This is fine, since we've
		// already set the position at which to resume when we're later reparented.
		// If we had instead considered this fatal, all tablets would crash-loop
		// until a master appears, which would make it impossible to elect a master.
		log.Warningf("Can't start replication after restore: shard %v/%v has no master.", tablet.Keyspace, tablet.Shard)
		return nil
	}
	if topoproto.TabletAliasEqual(si.MasterAlias, tablet.Alias) {
		// We used to be the master before we got restarted in an empty data dir,
		// and no other master has been elected in the meantime.
		// This shouldn't happen, so we'll let the operator decide which tablet
		// should actually be promoted to master.
		log.Warningf("Can't start replication after restore: master record still points to this tablet.")
		return nil
	}
	ti, err := agent.TopoServer.GetTablet(ctx, si.MasterAlias)
	if err != nil {
		return fmt.Errorf("Cannot read master tablet %v: %v", si.MasterAlias, err)
	}

	// If using semi-sync, we need to enable it before connecting to master.
	if *enableSemiSync {
		if err := agent.enableSemiSync(false); err != nil {
			return err
		}
	}

	// Set master and start slave.
	cmds, err = agent.MysqlDaemon.SetMasterCommands(ti.Hostname, int(ti.PortMap["mysql"]))
	if err != nil {
		return fmt.Errorf("MysqlDaemon.SetMasterCommands failed: %v", err)
	}
	cmds = append(cmds, "START SLAVE")
	if err := agent.MysqlDaemon.ExecuteSuperQueryList(ctx, cmds); err != nil {
		return fmt.Errorf("failed to start replication: %v", err)
	}

	return nil
}
Exemplo n.º 8
0
// DeleteTablet removes a tablet from a shard.
// - if allowMaster is set, we can Delete a master tablet (and clear
// its record from the Shard record if it was the master).
// - if skipRebuild is set, we do not rebuild the serving graph.
func (wr *Wrangler) DeleteTablet(ctx context.Context, tabletAlias *topodatapb.TabletAlias, allowMaster, skipRebuild bool) error {
	// load the tablet, see if we'll need to rebuild
	ti, err := wr.ts.GetTablet(ctx, tabletAlias)
	if err != nil {
		return err
	}
	rebuildRequired := ti.IsInServingGraph()
	wasMaster := ti.Type == topodatapb.TabletType_MASTER
	if wasMaster && !allowMaster {
		return fmt.Errorf("cannot delete tablet %v as it is a master, use allow_master flag", topoproto.TabletAliasString(tabletAlias))
	}

	// remove the record and its replication graph entry
	if err := topotools.DeleteTablet(ctx, wr.ts, ti.Tablet); err != nil {
		return err
	}

	// update the Shard object if the master was scrapped.
	// we lock the shard to not conflict with reparent operations.
	if wasMaster {
		actionNode := actionnode.UpdateShard()
		lockPath, err := wr.lockShard(ctx, ti.Keyspace, ti.Shard, actionNode)
		if err != nil {
			return err
		}

		// update the shard record's master
		if _, err := wr.ts.UpdateShardFields(ctx, ti.Keyspace, ti.Shard, func(s *topodatapb.Shard) error {
			if !topoproto.TabletAliasEqual(s.MasterAlias, tabletAlias) {
				wr.Logger().Warningf("Deleting master %v from shard %v/%v but master in Shard object was %v", topoproto.TabletAliasString(tabletAlias), ti.Keyspace, ti.Shard, topoproto.TabletAliasString(s.MasterAlias))
				return topo.ErrNoUpdateNeeded
			}
			s.MasterAlias = nil
			return nil
		}); err != nil {
			return wr.unlockShard(ctx, ti.Keyspace, ti.Shard, actionNode, lockPath, err)
		}

		// and unlock
		if err := wr.unlockShard(ctx, ti.Keyspace, ti.Shard, actionNode, lockPath, err); err != nil {
			return err
		}
	}

	// and rebuild the original shard if needed
	if !rebuildRequired {
		wr.Logger().Infof("Rebuild not required")
		return nil
	}
	if skipRebuild {
		wr.Logger().Warningf("Rebuild required, but skipping it")
		return nil
	}
	_, err = wr.RebuildShardGraph(ctx, ti.Keyspace, ti.Shard, []string{ti.Alias.Cell})
	return err
}
Exemplo n.º 9
0
// FIXME(msolomon) This validate presumes the master is up and running.
// Even when that isn't true, there are validation processes that might be valuable.
func (wr *Wrangler) validateShard(ctx context.Context, keyspace, shard string, pingTablets bool, wg *sync.WaitGroup, results chan<- error) {
	shardInfo, err := wr.ts.GetShard(ctx, keyspace, shard)
	if err != nil {
		results <- fmt.Errorf("TopologyServer.GetShard(%v, %v) failed: %v", keyspace, shard, err)
		return
	}

	aliases, err := wr.ts.FindAllTabletAliasesInShard(ctx, keyspace, shard)
	if err != nil {
		results <- fmt.Errorf("TopologyServer.FindAllTabletAliasesInShard(%v, %v) failed: %v", keyspace, shard, err)
		return
	}

	tabletMap, _ := wr.ts.GetTabletMap(ctx, aliases)

	var masterAlias *pb.TabletAlias
	for _, alias := range aliases {
		tabletInfo, ok := tabletMap[*alias]
		if !ok {
			results <- fmt.Errorf("tablet %v not found in map", topoproto.TabletAliasString(alias))
			continue
		}
		if tabletInfo.Type == pb.TabletType_MASTER {
			if masterAlias != nil {
				results <- fmt.Errorf("shard %v/%v already has master %v but found other master %v", keyspace, shard, topoproto.TabletAliasString(masterAlias), topoproto.TabletAliasString(alias))
			} else {
				masterAlias = alias
			}
		}
	}

	if masterAlias == nil {
		results <- fmt.Errorf("no master for shard %v/%v", keyspace, shard)
	} else if !topoproto.TabletAliasEqual(shardInfo.MasterAlias, masterAlias) {
		results <- fmt.Errorf("master mismatch for shard %v/%v: found %v, expected %v", keyspace, shard, topoproto.TabletAliasString(masterAlias), topoproto.TabletAliasString(shardInfo.MasterAlias))
	}

	for _, alias := range aliases {
		wg.Add(1)
		go func(alias *pb.TabletAlias) {
			defer wg.Done()
			if err := topo.Validate(ctx, wr.ts, alias); err != nil {
				results <- fmt.Errorf("Validate(%v) failed: %v", topoproto.TabletAliasString(alias), err)
			} else {
				wr.Logger().Infof("tablet %v is valid", topoproto.TabletAliasString(alias))
			}
		}(alias)
	}

	if pingTablets {
		wr.validateReplication(ctx, shardInfo, tabletMap, results)
		wr.pingTablets(ctx, tabletMap, wg, results)
	}

	return
}
Exemplo n.º 10
0
// Validate makes sure a tablet is represented correctly in the topology server.
func Validate(ctx context.Context, ts Server, tabletAlias *pb.TabletAlias) error {
	// read the tablet record, make sure it parses
	tablet, err := ts.GetTablet(ctx, tabletAlias)
	if err != nil {
		return err
	}
	if !topoproto.TabletAliasEqual(tablet.Alias, tabletAlias) {
		return fmt.Errorf("bad tablet alias data for tablet %v: %#v", topoproto.TabletAliasString(tabletAlias), tablet.Alias)
	}

	// Some tablets have no information to generate valid replication paths.
	// We have three cases to handle:
	// - we are a tablet in the replication graph, and should have
	//   replication data (first case below)
	// - we are in scrap mode but used to be assigned in the graph
	//   somewhere (second case below)
	// Idle tablets are just not in any graph at all, we don't even know
	// their keyspace / shard to know where to check.
	if tablet.IsInReplicationGraph() {
		if err = ts.ValidateShard(ctx, tablet.Keyspace, tablet.Shard); err != nil {
			return err
		}

		si, err := ts.GetShardReplication(ctx, tablet.Alias.Cell, tablet.Keyspace, tablet.Shard)
		if err != nil {
			return err
		}

		_, err = si.GetShardReplicationNode(tabletAlias)
		if err != nil {
			return fmt.Errorf("tablet %v not found in cell %v shard replication: %v", tabletAlias, tablet.Alias.Cell, err)
		}

	} else if tablet.IsAssigned() {
		// this case is to make sure a scrap node that used to be in
		// a replication graph doesn't leave a node behind.
		// However, while an action is running, there is some
		// time where this might be inconsistent.
		si, err := ts.GetShardReplication(ctx, tablet.Alias.Cell, tablet.Keyspace, tablet.Shard)
		if err != nil {
			return err
		}

		node, err := si.GetShardReplicationNode(tabletAlias)
		if err != ErrNoNode {
			return fmt.Errorf("unexpected replication data found(possible pending action?): %v (%v)", node, tablet.Type)
		}
	}

	return nil
}
Exemplo n.º 11
0
// updateShardCellsAndMaster will update the 'Cells' and possibly
// MasterAlias records for the shard, if needed.
func (wr *Wrangler) updateShardCellsAndMaster(ctx context.Context, si *topo.ShardInfo, tabletAlias *topodatapb.TabletAlias, tabletType topodatapb.TabletType, allowMasterOverride bool) error {
	// See if we need to update the Shard:
	// - add the tablet's cell to the shard's Cells if needed
	// - change the master if needed
	shardUpdateRequired := false
	if !si.HasCell(tabletAlias.Cell) {
		shardUpdateRequired = true
	}
	if tabletType == topodatapb.TabletType_MASTER && !topoproto.TabletAliasEqual(si.MasterAlias, tabletAlias) {
		shardUpdateRequired = true
	}
	if !shardUpdateRequired {
		return nil
	}

	// run the update
	_, err := wr.ts.UpdateShardFields(ctx, si.Keyspace(), si.ShardName(), func(s *topo.ShardInfo) error {
		wasUpdated := false
		if !s.HasCell(tabletAlias.Cell) {
			s.Cells = append(s.Cells, tabletAlias.Cell)
			wasUpdated = true
		}

		if tabletType == topodatapb.TabletType_MASTER && !topoproto.TabletAliasEqual(s.MasterAlias, tabletAlias) {
			if !topoproto.TabletAliasIsZero(s.MasterAlias) && !allowMasterOverride {
				return fmt.Errorf("creating this tablet would override old master %v in shard %v/%v", topoproto.TabletAliasString(s.MasterAlias), si.Keyspace(), si.ShardName())
			}
			s.MasterAlias = tabletAlias
			wasUpdated = true
		}

		if !wasUpdated {
			return topo.ErrNoUpdateNeeded
		}
		return nil
	})
	return err
}
Exemplo n.º 12
0
// TabletEquality returns true iff two Tablet are representing the same tablet
// process: same uid/cell, running on the same host / ports.
func TabletEquality(left, right *topodatapb.Tablet) bool {
	if !topoproto.TabletAliasEqual(left.Alias, right.Alias) {
		return false
	}
	if left.Hostname != right.Hostname {
		return false
	}
	if len(left.PortMap) != len(right.PortMap) {
		return false
	}
	for key, lvalue := range left.PortMap {
		rvalue, ok := right.PortMap[key]
		if !ok {
			return false
		}
		if lvalue != rvalue {
			return false
		}
	}
	return true
}
Exemplo n.º 13
0
// ValidateSchemaShard will diff the schema from all the tablets in the shard.
func (wr *Wrangler) ValidateSchemaShard(ctx context.Context, keyspace, shard string, excludeTables []string, includeViews bool) error {
	si, err := wr.ts.GetShard(ctx, keyspace, shard)
	if err != nil {
		return err
	}

	// get schema from the master, or error
	if !si.HasMaster() {
		return fmt.Errorf("No master in shard %v/%v", keyspace, shard)
	}
	log.Infof("Gathering schema for master %v", topoproto.TabletAliasString(si.MasterAlias))
	masterSchema, err := wr.GetSchema(ctx, si.MasterAlias, nil, excludeTables, includeViews)
	if err != nil {
		return err
	}

	// read all the aliases in the shard, that is all tablets that are
	// replicating from the master
	aliases, err := wr.ts.FindAllTabletAliasesInShard(ctx, keyspace, shard)
	if err != nil {
		return err
	}

	// then diff with all slaves
	er := concurrency.AllErrorRecorder{}
	wg := sync.WaitGroup{}
	for _, alias := range aliases {
		if topoproto.TabletAliasEqual(alias, si.MasterAlias) {
			continue
		}

		wg.Add(1)
		go wr.diffSchema(ctx, masterSchema, si.MasterAlias, alias, excludeTables, includeViews, &wg, &er)
	}
	wg.Wait()
	if er.HasErrors() {
		return fmt.Errorf("Schema diffs: %v", er.Error().Error())
	}
	return nil
}
Exemplo n.º 14
0
// DeleteTablet removes a tablet from a shard.
// - if allowMaster is set, we can Delete a master tablet (and clear
// its record from the Shard record if it was the master).
func (wr *Wrangler) DeleteTablet(ctx context.Context, tabletAlias *topodatapb.TabletAlias, allowMaster bool) (err error) {
	// load the tablet, see if we'll need to rebuild
	ti, err := wr.ts.GetTablet(ctx, tabletAlias)
	if err != nil {
		return err
	}
	wasMaster := ti.Type == topodatapb.TabletType_MASTER
	if wasMaster && !allowMaster {
		return fmt.Errorf("cannot delete tablet %v as it is a master, use allow_master flag", topoproto.TabletAliasString(tabletAlias))
	}

	// remove the record and its replication graph entry
	if err := topotools.DeleteTablet(ctx, wr.ts, ti.Tablet); err != nil {
		return err
	}

	// update the Shard object if the master was scrapped.
	if wasMaster {
		// We lock the shard to not conflict with reparent operations.
		ctx, unlock, lockErr := wr.ts.LockShard(ctx, ti.Keyspace, ti.Shard, fmt.Sprintf("DeleteTablet(%v)", topoproto.TabletAliasString(tabletAlias)))
		if lockErr != nil {
			return lockErr
		}
		defer unlock(&err)

		// update the shard record's master
		_, err = wr.ts.UpdateShardFields(ctx, ti.Keyspace, ti.Shard, func(si *topo.ShardInfo) error {
			if !topoproto.TabletAliasEqual(si.MasterAlias, tabletAlias) {
				wr.Logger().Warningf("Deleting master %v from shard %v/%v but master in Shard object was %v", topoproto.TabletAliasString(tabletAlias), ti.Keyspace, ti.Shard, topoproto.TabletAliasString(si.MasterAlias))
				return topo.ErrNoUpdateNeeded
			}
			si.MasterAlias = nil
			return nil
		})
		return err
	}

	return nil
}
Exemplo n.º 15
0
// ValidatePermissionsShard validates all the permissions are the same
// in a shard
func (wr *Wrangler) ValidatePermissionsShard(ctx context.Context, keyspace, shard string) error {
	si, err := wr.ts.GetShard(ctx, keyspace, shard)
	if err != nil {
		return err
	}

	// get permissions from the master, or error
	if !si.HasMaster() {
		return fmt.Errorf("No master in shard %v/%v", keyspace, shard)
	}
	log.Infof("Gathering permissions for master %v", topoproto.TabletAliasString(si.MasterAlias))
	masterPermissions, err := wr.GetPermissions(ctx, si.MasterAlias)
	if err != nil {
		return err
	}

	// read all the aliases in the shard, that is all tablets that are
	// replicating from the master
	aliases, err := wr.ts.FindAllTabletAliasesInShard(ctx, keyspace, shard)
	if err != nil {
		return err
	}

	// then diff all of them, except master
	er := concurrency.AllErrorRecorder{}
	wg := sync.WaitGroup{}
	for _, alias := range aliases {
		if topoproto.TabletAliasEqual(alias, si.MasterAlias) {
			continue
		}
		wg.Add(1)
		go wr.diffPermissions(ctx, masterPermissions, si.MasterAlias, alias, &wg, &er)
	}
	wg.Wait()
	if er.HasErrors() {
		return fmt.Errorf("Permissions diffs:\n%v", er.Error().Error())
	}
	return nil
}
Exemplo n.º 16
0
// chooseNewMaster finds a tablet that is going to become master after reparent. The criterias
// for the new master-elect are (preferably) to be in the same cell as the current master, and
// to be different from avoidMasterTabletAlias. The tablet with the largest replication
// position is chosen to minimize the time of catching up with the master. Note that the search
// for largest replication position will race with transactions being executed on the master at
// the same time, so when all tablets are roughly at the same position then the choice of the
// new master-elect will be somewhat unpredictable.
func (wr *Wrangler) chooseNewMaster(
	ctx context.Context,
	shardInfo *topo.ShardInfo,
	tabletMap map[topodatapb.TabletAlias]*topo.TabletInfo,
	avoidMasterTabletAlias *topodatapb.TabletAlias,
	waitSlaveTimeout time.Duration) (*topodatapb.TabletAlias, error) {

	if avoidMasterTabletAlias == nil {
		return nil, fmt.Errorf("tablet to avoid for reparent is not provided, cannot choose new master")
	}
	var masterCell string
	if shardInfo.MasterAlias != nil {
		masterCell = shardInfo.MasterAlias.Cell
	}

	maxPosSearch := maxReplPosSearch{
		wrangler:         wr,
		ctx:              ctx,
		waitSlaveTimeout: waitSlaveTimeout,
		waitGroup:        sync.WaitGroup{},
		maxPosLock:       sync.Mutex{},
	}
	for tabletAlias, tabletInfo := range tabletMap {
		if (masterCell != "" && tabletAlias.Cell != masterCell) ||
			topoproto.TabletAliasEqual(&tabletAlias, avoidMasterTabletAlias) {
			continue
		}
		maxPosSearch.waitGroup.Add(1)
		go maxPosSearch.processTablet(tabletInfo.Tablet)
	}
	maxPosSearch.waitGroup.Wait()

	if maxPosSearch.maxPosTablet == nil {
		return nil, nil
	}
	return maxPosSearch.maxPosTablet.Alias, nil
}
Exemplo n.º 17
0
func (wr *Wrangler) plannedReparentShardLocked(ctx context.Context, ev *events.Reparent, keyspace, shard string, masterElectTabletAlias *pb.TabletAlias, waitSlaveTimeout time.Duration) error {
	shardInfo, err := wr.ts.GetShard(ctx, keyspace, shard)
	if err != nil {
		return err
	}
	ev.ShardInfo = *shardInfo

	event.DispatchUpdate(ev, "reading tablet map")
	tabletMap, err := wr.ts.GetTabletMapForShard(ctx, keyspace, shard)
	if err != nil {
		return err
	}

	// Check corner cases we're going to depend on
	masterElectTabletInfo, ok := tabletMap[*masterElectTabletAlias]
	if !ok {
		return fmt.Errorf("master-elect tablet %v is not in the shard", topoproto.TabletAliasString(masterElectTabletAlias))
	}
	ev.NewMaster = *masterElectTabletInfo.Tablet
	if topoproto.TabletAliasEqual(shardInfo.MasterAlias, masterElectTabletAlias) {
		return fmt.Errorf("master-elect tablet %v is already the master", topoproto.TabletAliasString(masterElectTabletAlias))
	}
	oldMasterTabletInfo, ok := tabletMap[*shardInfo.MasterAlias]
	if !ok {
		return fmt.Errorf("old master tablet %v is not in the shard", topoproto.TabletAliasString(shardInfo.MasterAlias))
	}
	ev.OldMaster = *oldMasterTabletInfo.Tablet

	// Demote the current master, get its replication position
	wr.logger.Infof("demote current master %v", shardInfo.MasterAlias)
	event.DispatchUpdate(ev, "demoting old master")
	rp, err := wr.tmc.DemoteMaster(ctx, oldMasterTabletInfo)
	if err != nil {
		return fmt.Errorf("old master tablet %v DemoteMaster failed: %v", topoproto.TabletAliasString(shardInfo.MasterAlias), err)
	}

	// Wait on the master-elect tablet until it reaches that position,
	// then promote it
	wr.logger.Infof("promote slave %v", topoproto.TabletAliasString(masterElectTabletAlias))
	event.DispatchUpdate(ev, "promoting slave")
	rp, err = wr.tmc.PromoteSlaveWhenCaughtUp(ctx, masterElectTabletInfo, rp)
	if err != nil {
		return fmt.Errorf("master-elect tablet %v failed to catch up with replication or be upgraded to master: %v", topoproto.TabletAliasString(masterElectTabletAlias), err)
	}

	// Go through all the tablets:
	// - new master: populate the reparent journal
	// - everybody else: reparent to new master, wait for row
	event.DispatchUpdate(ev, "reparenting all tablets")
	now := time.Now().UnixNano()
	wgMaster := sync.WaitGroup{}
	wgSlaves := sync.WaitGroup{}
	rec := concurrency.AllErrorRecorder{}
	var masterErr error
	for alias, tabletInfo := range tabletMap {
		if topoproto.TabletAliasEqual(&alias, masterElectTabletAlias) {
			wgMaster.Add(1)
			go func(alias pb.TabletAlias, tabletInfo *topo.TabletInfo) {
				defer wgMaster.Done()
				wr.logger.Infof("populating reparent journal on new master %v", topoproto.TabletAliasString(&alias))
				masterErr = wr.TabletManagerClient().PopulateReparentJournal(ctx, tabletInfo, now, plannedReparentShardOperation, &alias, rp)
			}(alias, tabletInfo)
		} else {
			wgSlaves.Add(1)
			go func(alias pb.TabletAlias, tabletInfo *topo.TabletInfo) {
				defer wgSlaves.Done()
				wr.logger.Infof("setting new master on slave %v", topoproto.TabletAliasString(&alias))
				// also restart replication on old master
				forceStartSlave := topoproto.TabletAliasEqual(&alias, oldMasterTabletInfo.Alias)
				if err := wr.TabletManagerClient().SetMaster(ctx, tabletInfo, masterElectTabletAlias, now, forceStartSlave); err != nil {
					rec.RecordError(fmt.Errorf("Tablet %v SetMaster failed: %v", topoproto.TabletAliasString(&alias), err))
					return
				}
			}(alias, tabletInfo)
		}
	}

	// After the master is done, we can update the shard record
	// (note with semi-sync, it also means at least one slave is done)
	wgMaster.Wait()
	if masterErr != nil {
		wgSlaves.Wait()
		return fmt.Errorf("failed to PopulateReparentJournal on master: %v", masterErr)
	}
	wr.logger.Infof("updating shard record with new master %v", masterElectTabletAlias)
	shardInfo.MasterAlias = masterElectTabletAlias
	if err := wr.ts.UpdateShard(ctx, shardInfo); err != nil {
		wgSlaves.Wait()
		return fmt.Errorf("failed to update shard master record: %v", err)
	}

	// Wait for the slaves to complete. If some of them fail, we
	// will rebuild the shard serving graph anyway
	wgSlaves.Wait()
	if err := rec.Error(); err != nil {
		wr.Logger().Errorf("Some slaves failed to reparent: %v", err)
		return err
	}

	// Then we rebuild the entire serving graph for the shard,
	// to account for all changes.
	wr.logger.Infof("rebuilding shard graph")
	event.DispatchUpdate(ev, "rebuilding shard serving graph")
	_, err = wr.RebuildShardGraph(ctx, keyspace, shard, nil)
	return err
}
Exemplo n.º 18
0
func (wr *Wrangler) initShardMasterLocked(ctx context.Context, ev *events.Reparent, keyspace, shard string, masterElectTabletAlias *pb.TabletAlias, force bool, waitSlaveTimeout time.Duration) error {
	shardInfo, err := wr.ts.GetShard(ctx, keyspace, shard)
	if err != nil {
		return err
	}
	ev.ShardInfo = *shardInfo

	event.DispatchUpdate(ev, "reading tablet map")
	tabletMap, err := wr.ts.GetTabletMapForShard(ctx, keyspace, shard)
	if err != nil {
		return err
	}

	// Check the master elect is in tabletMap
	masterElectTabletInfo, ok := tabletMap[*masterElectTabletAlias]
	if !ok {
		return fmt.Errorf("master-elect tablet %v is not in the shard", topoproto.TabletAliasString(masterElectTabletAlias))
	}
	ev.NewMaster = *masterElectTabletInfo.Tablet

	// Check the master is the only master is the shard, or -force was used.
	_, masterTabletMap := topotools.SortedTabletMap(tabletMap)
	if !topoproto.TabletAliasEqual(shardInfo.MasterAlias, masterElectTabletAlias) {
		if !force {
			return fmt.Errorf("master-elect tablet %v is not the shard master, use -force to proceed anyway", topoproto.TabletAliasString(masterElectTabletAlias))
		}
		wr.logger.Warningf("master-elect tablet %v is not the shard master, proceeding anyway as -force was used", topoproto.TabletAliasString(masterElectTabletAlias))
	}
	if _, ok := masterTabletMap[*masterElectTabletAlias]; !ok {
		if !force {
			return fmt.Errorf("master-elect tablet %v is not a master in the shard, use -force to proceed anyway", topoproto.TabletAliasString(masterElectTabletAlias))
		}
		wr.logger.Warningf("master-elect tablet %v is not a master in the shard, proceeding anyway as -force was used", topoproto.TabletAliasString(masterElectTabletAlias))
	}
	haveOtherMaster := false
	for alias, ti := range masterTabletMap {
		if !topoproto.TabletAliasEqual(&alias, masterElectTabletAlias) && ti.Type != pb.TabletType_SCRAP {
			haveOtherMaster = true
		}
	}
	if haveOtherMaster {
		if !force {
			return fmt.Errorf("master-elect tablet %v is not the only master in the shard, use -force to proceed anyway", topoproto.TabletAliasString(masterElectTabletAlias))
		}
		wr.logger.Warningf("master-elect tablet %v is not the only master in the shard, proceeding anyway as -force was used", topoproto.TabletAliasString(masterElectTabletAlias))
	}

	// First phase: reset replication on all tablets. If anyone fails,
	// we stop. It is probably because it is unreachable, and may leave
	// an unstable database process in the mix, with a database daemon
	// at a wrong replication spot.
	event.DispatchUpdate(ev, "resetting replication on all tablets")
	wg := sync.WaitGroup{}
	rec := concurrency.AllErrorRecorder{}
	for alias, tabletInfo := range tabletMap {
		wg.Add(1)
		go func(alias pb.TabletAlias, tabletInfo *topo.TabletInfo) {
			defer wg.Done()
			wr.logger.Infof("resetting replication on tablet %v", topoproto.TabletAliasString(&alias))
			if err := wr.TabletManagerClient().ResetReplication(ctx, tabletInfo); err != nil {
				rec.RecordError(fmt.Errorf("Tablet %v ResetReplication failed (either fix it, or Scrap it): %v", topoproto.TabletAliasString(&alias), err))
			}
		}(alias, tabletInfo)
	}
	wg.Wait()
	if err := rec.Error(); err != nil {
		return err
	}

	// Tell the new master to break its slaves, return its replication
	// position
	wr.logger.Infof("initializing master on %v", topoproto.TabletAliasString(masterElectTabletAlias))
	event.DispatchUpdate(ev, "initializing master")
	rp, err := wr.TabletManagerClient().InitMaster(ctx, masterElectTabletInfo)
	if err != nil {
		return err
	}

	// Now tell the new master to insert the reparent_journal row,
	// and tell everybody else to become a slave of the new master,
	// and wait for the row in the reparent_journal table.
	// We start all these in parallel, to handle the semi-sync
	// case: for the master to be able to commit its row in the
	// reparent_journal table, it needs connected slaves.
	event.DispatchUpdate(ev, "reparenting all tablets")
	now := time.Now().UnixNano()
	wgMaster := sync.WaitGroup{}
	wgSlaves := sync.WaitGroup{}
	var masterErr error
	for alias, tabletInfo := range tabletMap {
		if topoproto.TabletAliasEqual(&alias, masterElectTabletAlias) {
			wgMaster.Add(1)
			go func(alias pb.TabletAlias, tabletInfo *topo.TabletInfo) {
				defer wgMaster.Done()
				wr.logger.Infof("populating reparent journal on new master %v", topoproto.TabletAliasString(&alias))
				masterErr = wr.TabletManagerClient().PopulateReparentJournal(ctx, tabletInfo, now, initShardMasterOperation, &alias, rp)
			}(alias, tabletInfo)
		} else {
			wgSlaves.Add(1)
			go func(alias pb.TabletAlias, tabletInfo *topo.TabletInfo) {
				defer wgSlaves.Done()
				wr.logger.Infof("initializing slave %v", topoproto.TabletAliasString(&alias))
				if err := wr.TabletManagerClient().InitSlave(ctx, tabletInfo, masterElectTabletAlias, rp, now); err != nil {
					rec.RecordError(fmt.Errorf("Tablet %v InitSlave failed: %v", topoproto.TabletAliasString(&alias), err))
				}
			}(alias, tabletInfo)
		}
	}

	// After the master is done, we can update the shard record
	// (note with semi-sync, it also means at least one slave is done)
	wgMaster.Wait()
	if masterErr != nil {
		wgSlaves.Wait()
		return fmt.Errorf("failed to PopulateReparentJournal on master: %v", masterErr)
	}
	if !topoproto.TabletAliasEqual(shardInfo.MasterAlias, masterElectTabletAlias) {
		shardInfo.MasterAlias = masterElectTabletAlias
		if err := wr.ts.UpdateShard(ctx, shardInfo); err != nil {
			wgSlaves.Wait()
			return fmt.Errorf("failed to update shard master record: %v", err)
		}
	}

	// Wait for the slaves to complete. If some of them fail, we
	// don't want to rebuild the shard serving graph (the failure
	// will most likely be a timeout, and our context will be
	// expired, so the rebuild will fail anyway)
	wgSlaves.Wait()
	if err := rec.Error(); err != nil {
		return err
	}

	// Then we rebuild the entire serving graph for the shard,
	// to account for all changes.
	event.DispatchUpdate(ev, "rebuilding shard graph")
	_, err = wr.RebuildShardGraph(ctx, keyspace, shard, nil)
	return err
}
Exemplo n.º 19
0
func TestTabletExternallyReparented(t *testing.T) {
	tabletmanager.SetReparentFlags(time.Minute /* finalizeTimeout */)

	ctx := context.Background()
	db := fakesqldb.Register()
	ts := zktopo.NewTestServer(t, []string{"cell1", "cell2"})
	wr := wrangler.New(logutil.NewConsoleLogger(), ts, tmclient.NewTabletManagerClient(), time.Second)
	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, pb.TabletType_MASTER, db)
	newMaster := NewFakeTablet(t, wr, "cell1", 1, pb.TabletType_REPLICA, db)
	goodSlave1 := NewFakeTablet(t, wr, "cell1", 2, pb.TabletType_REPLICA, db)
	goodSlave2 := NewFakeTablet(t, wr, "cell2", 3, pb.TabletType_REPLICA, db)
	badSlave := NewFakeTablet(t, wr, "cell1", 4, pb.TabletType_REPLICA, db)

	// Add a new Cell to the Shard, that doesn't map to any read topo cell,
	// to simulate a data center being unreachable.
	si, err := ts.GetShard(ctx, "test_keyspace", "0")
	if err != nil {
		t.Fatalf("GetShard failed: %v", err)
	}
	si.Cells = append(si.Cells, "cell666")
	if err := ts.UpdateShard(ctx, si); err != nil {
		t.Fatalf("UpdateShard failed: %v", err)
	}

	// Slightly unrelated test: make sure we can find the tablets
	// even with a datacenter being down.
	tabletMap, err := ts.GetTabletMapForShardByCell(ctx, "test_keyspace", "0", []string{"cell1"})
	if err != nil {
		t.Fatalf("GetTabletMapForShardByCell should have worked but got: %v", err)
	}
	master, err := topotools.FindTabletByIPAddrAndPort(tabletMap, oldMaster.Tablet.Ip, "vt", oldMaster.Tablet.PortMap["vt"])
	if err != nil || !topoproto.TabletAliasEqual(&master, oldMaster.Tablet.Alias) {
		t.Fatalf("FindTabletByIPAddrAndPort(master) failed: %v %v", err, master)
	}
	slave1, err := topotools.FindTabletByIPAddrAndPort(tabletMap, goodSlave1.Tablet.Ip, "vt", goodSlave1.Tablet.PortMap["vt"])
	if err != nil || !topoproto.TabletAliasEqual(&slave1, goodSlave1.Tablet.Alias) {
		t.Fatalf("FindTabletByIPAddrAndPort(slave1) failed: %v %v", err, master)
	}
	slave2, err := topotools.FindTabletByIPAddrAndPort(tabletMap, goodSlave2.Tablet.Ip, "vt", goodSlave2.Tablet.PortMap["vt"])
	if err != topo.ErrNoNode {
		t.Fatalf("FindTabletByIPAddrAndPort(slave2) worked: %v %v", err, slave2)
	}

	// Make sure the master is not exported in other cells
	tabletMap, err = ts.GetTabletMapForShardByCell(ctx, "test_keyspace", "0", []string{"cell2"})
	master, err = topotools.FindTabletByIPAddrAndPort(tabletMap, oldMaster.Tablet.Ip, "vt", oldMaster.Tablet.PortMap["vt"])
	if err != topo.ErrNoNode {
		t.Fatalf("FindTabletByIPAddrAndPort(master) worked in cell2: %v %v", err, master)
	}

	tabletMap, err = ts.GetTabletMapForShard(ctx, "test_keyspace", "0")
	if err != topo.ErrPartialResult {
		t.Fatalf("GetTabletMapForShard should have returned ErrPartialResult but got: %v", err)
	}
	master, err = topotools.FindTabletByIPAddrAndPort(tabletMap, oldMaster.Tablet.Ip, "vt", oldMaster.Tablet.PortMap["vt"])
	if err != nil || !topoproto.TabletAliasEqual(&master, oldMaster.Tablet.Alias) {
		t.Fatalf("FindTabletByIPAddrAndPort(master) failed: %v %v", err, master)
	}

	// On the elected master, we will respond to
	// TabletActionSlaveWasPromoted
	newMaster.StartActionLoop(t, wr)
	defer newMaster.StopActionLoop(t)

	// On the old master, we will only respond to
	// TabletActionSlaveWasRestarted.
	oldMaster.StartActionLoop(t, wr)
	defer oldMaster.StopActionLoop(t)

	// On the good slaves, we will respond to
	// TabletActionSlaveWasRestarted.
	goodSlave1.StartActionLoop(t, wr)
	defer goodSlave1.StopActionLoop(t)

	goodSlave2.StartActionLoop(t, wr)
	defer goodSlave2.StopActionLoop(t)

	// On the bad slave, we will respond to
	// TabletActionSlaveWasRestarted with bad data.
	badSlave.StartActionLoop(t, wr)
	defer badSlave.StopActionLoop(t)

	// First test: reparent to the same master, make sure it works
	// as expected.
	tmc := tmclient.NewTabletManagerClient()
	ti, err := ts.GetTablet(ctx, oldMaster.Tablet.Alias)
	if err != nil {
		t.Fatalf("GetTablet failed: %v", err)
	}
	if err := vp.Run([]string{"TabletExternallyReparented", topoproto.TabletAliasString(oldMaster.Tablet.Alias)}); err != nil {
		t.Fatalf("TabletExternallyReparented(same master) should have worked: %v", err)
	}

	// Second test: reparent to a replica, and pretend the old
	// master is still good to go.

	// This tests a bad case; the new designated master is a slave,
	// but we should do what we're told anyway
	ti, err = ts.GetTablet(ctx, goodSlave1.Tablet.Alias)
	if err != nil {
		t.Fatalf("GetTablet failed: %v", err)
	}
	waitID := makeWaitID()
	if err := tmc.TabletExternallyReparented(context.Background(), ti, waitID); err != nil {
		t.Fatalf("TabletExternallyReparented(slave) error: %v", err)
	}
	waitForExternalReparent(t, waitID)

	// This tests the good case, where everything works as planned
	t.Logf("TabletExternallyReparented(new master) expecting success")
	ti, err = ts.GetTablet(ctx, newMaster.Tablet.Alias)
	if err != nil {
		t.Fatalf("GetTablet failed: %v", err)
	}
	waitID = makeWaitID()
	if err := tmc.TabletExternallyReparented(context.Background(), ti, waitID); err != nil {
		t.Fatalf("TabletExternallyReparented(replica) failed: %v", err)
	}
	waitForExternalReparent(t, waitID)

	// Now double-check the serving graph is good.
	// Should only have one good replica left.
	addrs, _, err := ts.GetEndPoints(ctx, "cell1", "test_keyspace", "0", pb.TabletType_REPLICA)
	if err != nil {
		t.Fatalf("GetEndPoints failed at the end: %v", err)
	}
	if len(addrs.Entries) != 1 {
		t.Fatalf("GetEndPoints has too many entries: %v", addrs)
	}
}
Exemplo n.º 20
0
// TestInitMasterShard is the good scenario test, where everything
// works as planned
func TestInitMasterShard(t *testing.T) {
	ctx := context.Background()
	db := fakesqldb.Register()
	ts := zktestserver.New(t, []string{"cell1", "cell2"})
	wr := wrangler.New(logutil.NewConsoleLogger(), ts, tmclient.NewTabletManagerClient())
	vp := NewVtctlPipe(t, ts)
	defer vp.Close()

	db.AddQuery("CREATE DATABASE IF NOT EXISTS `vt_test_keyspace`", &sqltypes.Result{})

	// Create a master, a couple good slaves
	master := NewFakeTablet(t, wr, "cell1", 0, topodatapb.TabletType_MASTER, db)
	goodSlave1 := NewFakeTablet(t, wr, "cell1", 1, topodatapb.TabletType_REPLICA, db)
	goodSlave2 := NewFakeTablet(t, wr, "cell2", 2, topodatapb.TabletType_REPLICA, db)

	// Master: set a plausible ReplicationPosition to return,
	// and expect to add entry in _vt.reparent_journal
	master.FakeMysqlDaemon.CurrentMasterPosition = replication.Position{
		GTIDSet: replication.MariadbGTID{
			Domain:   5,
			Server:   456,
			Sequence: 890,
		},
	}
	master.FakeMysqlDaemon.ReadOnly = true
	master.FakeMysqlDaemon.ResetReplicationResult = []string{"reset rep 1"}
	master.FakeMysqlDaemon.SetSlavePositionCommandsResult = []string{"new master shouldn't use this"}
	master.FakeMysqlDaemon.SetMasterCommandsResult = []string{"new master shouldn't use this"}
	master.FakeMysqlDaemon.ExpectedExecuteSuperQueryList = []string{
		"reset rep 1",
		"CREATE DATABASE IF NOT EXISTS _vt",
		"SUBCREATE TABLE IF NOT EXISTS _vt.reparent_journal",
		"CREATE DATABASE IF NOT EXISTS _vt",
		"SUBCREATE TABLE IF NOT EXISTS _vt.reparent_journal",
		"SUBINSERT INTO _vt.reparent_journal (time_created_ns, action_name, master_alias, replication_position) VALUES",
	}
	master.StartActionLoop(t, wr)
	defer master.StopActionLoop(t)

	// Slave1: expect to be reset and re-parented
	goodSlave1.FakeMysqlDaemon.ReadOnly = true
	goodSlave1.FakeMysqlDaemon.ResetReplicationResult = []string{"reset rep 1"}
	goodSlave1.FakeMysqlDaemon.SetSlavePositionCommandsPos = master.FakeMysqlDaemon.CurrentMasterPosition
	goodSlave1.FakeMysqlDaemon.SetSlavePositionCommandsResult = []string{"cmd1"}
	goodSlave1.FakeMysqlDaemon.SetMasterCommandsInput = fmt.Sprintf("%v:%v", master.Tablet.Hostname, master.Tablet.PortMap["mysql"])
	goodSlave1.FakeMysqlDaemon.SetMasterCommandsResult = []string{"set master cmd 1"}
	goodSlave1.FakeMysqlDaemon.ExpectedExecuteSuperQueryList = []string{
		"reset rep 1",
		"cmd1",
		"set master cmd 1",
		"START SLAVE",
	}
	goodSlave1.StartActionLoop(t, wr)
	defer goodSlave1.StopActionLoop(t)

	// Slave2: expect to be re-parented
	goodSlave2.FakeMysqlDaemon.ReadOnly = true
	goodSlave2.FakeMysqlDaemon.ResetReplicationResult = []string{"reset rep 2"}
	goodSlave2.FakeMysqlDaemon.SetSlavePositionCommandsPos = master.FakeMysqlDaemon.CurrentMasterPosition
	goodSlave2.FakeMysqlDaemon.SetSlavePositionCommandsResult = []string{"cmd1", "cmd2"}
	goodSlave2.FakeMysqlDaemon.SetMasterCommandsInput = fmt.Sprintf("%v:%v", master.Tablet.Hostname, master.Tablet.PortMap["mysql"])
	goodSlave2.FakeMysqlDaemon.SetMasterCommandsResult = []string{"set master cmd 1"}
	goodSlave2.FakeMysqlDaemon.ExpectedExecuteSuperQueryList = []string{
		"reset rep 2",
		"cmd1",
		"cmd2",
		"set master cmd 1",
		"START SLAVE",
	}
	goodSlave2.StartActionLoop(t, wr)
	defer goodSlave2.StopActionLoop(t)

	// run InitShardMaster
	if err := vp.Run([]string{"InitShardMaster", "-wait_slave_timeout", "10s", master.Tablet.Keyspace + "/" + master.Tablet.Shard, topoproto.TabletAliasString(master.Tablet.Alias)}); err != nil {
		t.Fatalf("InitShardMaster failed: %v", err)
	}

	// check what was run
	if master.FakeMysqlDaemon.ReadOnly {
		t.Errorf("master was not turned read-write")
	}
	si, err := ts.GetShard(ctx, master.Tablet.Keyspace, master.Tablet.Shard)
	if err != nil {
		t.Fatalf("GetShard failed: %v", err)
	}
	if !topoproto.TabletAliasEqual(si.MasterAlias, master.Tablet.Alias) {
		t.Errorf("unexpected shard master alias, got %v expected %v", si.MasterAlias, master.Tablet.Alias)
	}
	if err := master.FakeMysqlDaemon.CheckSuperQueryList(); err != nil {
		t.Fatalf("master.FakeMysqlDaemon.CheckSuperQueryList failed: %v", err)
	}
	if err := goodSlave1.FakeMysqlDaemon.CheckSuperQueryList(); err != nil {
		t.Fatalf("goodSlave1.FakeMysqlDaemon.CheckSuperQueryList failed: %v", err)
	}
	if err := goodSlave2.FakeMysqlDaemon.CheckSuperQueryList(); err != nil {
		t.Fatalf("goodSlave2.FakeMysqlDaemon.CheckSuperQueryList failed: %v", err)
	}
}
Exemplo n.º 21
0
// TestInitMasterShardOneSlaveFails makes sure that if one slave fails to
// proceed, the action completes anyway
func TestInitMasterShardOneSlaveFails(t *testing.T) {
	ctx := context.Background()
	db := fakesqldb.Register()
	ts := zktestserver.New(t, []string{"cell1", "cell2"})
	wr := wrangler.New(logutil.NewConsoleLogger(), ts, tmclient.NewTabletManagerClient())

	// Create a master, a couple slaves
	master := NewFakeTablet(t, wr, "cell1", 0, topodatapb.TabletType_MASTER, db)
	goodSlave := NewFakeTablet(t, wr, "cell1", 1, topodatapb.TabletType_REPLICA, db)
	badSlave := NewFakeTablet(t, wr, "cell2", 2, topodatapb.TabletType_REPLICA, db)

	// Master: set a plausible ReplicationPosition to return,
	// and expect to add entry in _vt.reparent_journal
	master.FakeMysqlDaemon.CurrentMasterPosition = replication.Position{
		GTIDSet: replication.MariadbGTID{
			Domain:   5,
			Server:   456,
			Sequence: 890,
		},
	}
	master.FakeMysqlDaemon.ReadOnly = true
	master.FakeMysqlDaemon.ExpectedExecuteSuperQueryList = []string{
		"CREATE DATABASE IF NOT EXISTS _vt",
		"SUBCREATE TABLE IF NOT EXISTS _vt.reparent_journal",
		"CREATE DATABASE IF NOT EXISTS _vt",
		"SUBCREATE TABLE IF NOT EXISTS _vt.reparent_journal",
		"SUBINSERT INTO _vt.reparent_journal (time_created_ns, action_name, master_alias, replication_position) VALUES",
	}
	master.StartActionLoop(t, wr)
	defer master.StopActionLoop(t)

	// goodSlave: expect to be re-parented
	goodSlave.FakeMysqlDaemon.ReadOnly = true
	goodSlave.FakeMysqlDaemon.SetSlavePositionCommandsPos = master.FakeMysqlDaemon.CurrentMasterPosition
	goodSlave.FakeMysqlDaemon.SetSlavePositionCommandsResult = []string{"cmd1"}
	goodSlave.FakeMysqlDaemon.SetMasterCommandsInput = fmt.Sprintf("%v:%v", master.Tablet.Hostname, master.Tablet.PortMap["mysql"])
	goodSlave.FakeMysqlDaemon.SetMasterCommandsResult = []string{"set master cmd 1"}
	goodSlave.FakeMysqlDaemon.ExpectedExecuteSuperQueryList = []string{
		"cmd1",
		"set master cmd 1",
		"START SLAVE",
	}
	goodSlave.StartActionLoop(t, wr)
	defer goodSlave.StopActionLoop(t)

	// badSlave: insert an error by failing the master hostname input
	// on purpose
	badSlave.FakeMysqlDaemon.ReadOnly = true
	badSlave.FakeMysqlDaemon.SetSlavePositionCommandsPos = master.FakeMysqlDaemon.CurrentMasterPosition
	badSlave.FakeMysqlDaemon.SetMasterCommandsInput = fmt.Sprintf("%v:%v", "", master.Tablet.PortMap["mysql"])
	badSlave.StartActionLoop(t, wr)
	defer badSlave.StopActionLoop(t)

	// also change the master alias in the Shard object, to make sure it
	// is set back.
	si, err := ts.GetShard(ctx, master.Tablet.Keyspace, master.Tablet.Shard)
	if err != nil {
		t.Fatalf("GetShard failed: %v", err)
	}
	si.MasterAlias.Uid++
	if err := ts.UpdateShard(ctx, si); err != nil {
		t.Fatalf("UpdateShard failed: %v", err)
	}

	// run InitShardMaster without force, it fails because master is
	// changing.
	if err := wr.InitShardMaster(ctx, master.Tablet.Keyspace, master.Tablet.Shard, master.Tablet.Alias, false /*force*/, 10*time.Second); err == nil || !strings.Contains(err.Error(), "is not the shard master") {
		t.Errorf("InitShardMaster with mismatched new master returned wrong error: %v", err)
	}

	// run InitShardMaster
	if err := wr.InitShardMaster(ctx, master.Tablet.Keyspace, master.Tablet.Shard, master.Tablet.Alias, true /*force*/, 10*time.Second); err == nil || !strings.Contains(err.Error(), "wrong input for SetMasterCommands") {
		t.Errorf("InitShardMaster with one failed slave returned wrong error: %v", err)
	}

	// check what was run: master should still be good
	if master.FakeMysqlDaemon.ReadOnly {
		t.Errorf("master was not turned read-write")
	}
	si, err = ts.GetShard(ctx, master.Tablet.Keyspace, master.Tablet.Shard)
	if err != nil {
		t.Fatalf("GetShard failed: %v", err)
	}
	if !topoproto.TabletAliasEqual(si.MasterAlias, master.Tablet.Alias) {
		t.Errorf("unexpected shard master alias, got %v expected %v", si.MasterAlias, master.Tablet.Alias)
	}
}
Exemplo n.º 22
0
// TabletExternallyReparented updates all topo records so the current
// tablet is the new master for this shard.
// Should be called under RPCWrapLock.
func (agent *ActionAgent) TabletExternallyReparented(ctx context.Context, externalID string) error {
	startTime := time.Now()

	// If there is a finalize step running, wait for it to finish or time out
	// before checking the global shard record again.
	if agent.finalizeReparentCtx != nil {
		select {
		case <-agent.finalizeReparentCtx.Done():
			agent.finalizeReparentCtx = nil
		case <-ctx.Done():
			return ctx.Err()
		}
	}

	tablet := agent.Tablet()

	// Check the global shard record.
	si, err := agent.TopoServer.GetShard(ctx, tablet.Keyspace, tablet.Shard)
	if err != nil {
		log.Warningf("fastTabletExternallyReparented: failed to read global shard record for %v/%v: %v", tablet.Keyspace, tablet.Shard, err)
		return err
	}
	if topoproto.TabletAliasEqual(si.MasterAlias, tablet.Alias) {
		// We may get called on the current master even when nothing has changed.
		// If the global shard record is already updated, it means we successfully
		// finished a previous reparent to this tablet.
		return nil
	}

	// Create a reusable Reparent event with available info.
	ev := &events.Reparent{
		ShardInfo: *si,
		NewMaster: *tablet.Tablet,
		OldMaster: pb.Tablet{
			Alias: si.MasterAlias,
			Type:  pb.TabletType_MASTER,
		},
		ExternalID: externalID,
	}
	defer func() {
		if err != nil {
			event.DispatchUpdate(ev, "failed: "+err.Error())
		}
	}()
	event.DispatchUpdate(ev, "starting external from tablet (fast)")

	// Execute state change to master by force-updating only the local copy of the
	// tablet record. The actual record in topo will be updated later.
	log.Infof("fastTabletExternallyReparented: executing change callback for state change to MASTER")
	oldTablet := *tablet.Tablet
	newTablet := oldTablet
	newTablet.Type = pb.TabletType_MASTER
	newTablet.HealthMap = nil
	agent.setTablet(topo.NewTabletInfo(&newTablet, -1))
	if err := agent.updateState(ctx, &oldTablet, "fastTabletExternallyReparented"); err != nil {
		return fmt.Errorf("fastTabletExternallyReparented: failed to change tablet state to MASTER: %v", err)
	}

	agent.mutex.Lock()
	agent._tabletExternallyReparentedTime = time.Now()
	agent.mutex.Unlock()

	// Directly write the new master endpoint in the serving graph.
	// We will do a true rebuild in the background soon, but in the meantime,
	// this will be enough for clients to re-resolve the new master.
	event.DispatchUpdate(ev, "writing new master endpoint")
	log.Infof("fastTabletExternallyReparented: writing new master endpoint to serving graph")
	ep, err := topo.TabletEndPoint(tablet.Tablet)
	if err != nil {
		return fmt.Errorf("fastTabletExternallyReparented: failed to generate EndPoint for tablet %v: %v", tablet.Alias, err)
	}
	err = topo.UpdateEndPoints(ctx, agent.TopoServer, tablet.Alias.Cell,
		si.Keyspace(), si.ShardName(), pb.TabletType_MASTER,
		&pb.EndPoints{Entries: []*pb.EndPoint{ep}}, -1)
	if err != nil {
		return fmt.Errorf("fastTabletExternallyReparented: failed to update master endpoint: %v", err)
	}
	externalReparentStats.Record("NewMasterVisible", startTime)

	// Start the finalize stage with a background context, but connect the trace.
	bgCtx, cancel := context.WithTimeout(agent.batchCtx, *finalizeReparentTimeout)
	bgCtx = trace.CopySpan(bgCtx, ctx)
	agent.finalizeReparentCtx = bgCtx
	go func() {
		err := agent.finalizeTabletExternallyReparented(bgCtx, si, ev)
		cancel()

		if err != nil {
			log.Warningf("finalizeTabletExternallyReparented error: %v", err)
			event.DispatchUpdate(ev, "failed: "+err.Error())
			return
		}
		externalReparentStats.Record("FullRebuild", startTime)
	}()

	return nil
}
Exemplo n.º 23
0
// ValidateSchemaKeyspace will diff the schema from all the tablets in
// the keyspace.
func (wr *Wrangler) ValidateSchemaKeyspace(ctx context.Context, keyspace string, excludeTables []string, includeViews bool) error {
	// find all the shards
	shards, err := wr.ts.GetShardNames(ctx, keyspace)
	if err != nil {
		return err
	}

	// corner cases
	if len(shards) == 0 {
		return fmt.Errorf("No shards in keyspace %v", keyspace)
	}
	sort.Strings(shards)
	if len(shards) == 1 {
		return wr.ValidateSchemaShard(ctx, keyspace, shards[0], excludeTables, includeViews)
	}

	// find the reference schema using the first shard's master
	si, err := wr.ts.GetShard(ctx, keyspace, shards[0])
	if err != nil {
		return err
	}
	if !si.HasMaster() {
		return fmt.Errorf("No master in shard %v/%v", keyspace, shards[0])
	}
	referenceAlias := si.MasterAlias
	log.Infof("Gathering schema for reference master %v", topoproto.TabletAliasString(referenceAlias))
	referenceSchema, err := wr.GetSchema(ctx, referenceAlias, nil, excludeTables, includeViews)
	if err != nil {
		return err
	}

	// then diff with all other tablets everywhere
	er := concurrency.AllErrorRecorder{}
	wg := sync.WaitGroup{}

	// first diff the slaves in the reference shard 0
	aliases, err := wr.ts.FindAllTabletAliasesInShard(ctx, keyspace, shards[0])
	if err != nil {
		return err
	}

	for _, alias := range aliases {
		if topoproto.TabletAliasEqual(alias, si.MasterAlias) {
			continue
		}

		wg.Add(1)
		go wr.diffSchema(ctx, referenceSchema, referenceAlias, alias, excludeTables, includeViews, &wg, &er)
	}

	// then diffs all tablets in the other shards
	for _, shard := range shards[1:] {
		si, err := wr.ts.GetShard(ctx, keyspace, shard)
		if err != nil {
			er.RecordError(err)
			continue
		}

		if !si.HasMaster() {
			er.RecordError(fmt.Errorf("No master in shard %v/%v", keyspace, shard))
			continue
		}

		aliases, err := wr.ts.FindAllTabletAliasesInShard(ctx, keyspace, shard)
		if err != nil {
			er.RecordError(err)
			continue
		}

		for _, alias := range aliases {
			wg.Add(1)
			go wr.diffSchema(ctx, referenceSchema, referenceAlias, alias, excludeTables, includeViews, &wg, &er)
		}
	}
	wg.Wait()
	if er.HasErrors() {
		return fmt.Errorf("Schema diffs: %v", er.Error().Error())
	}
	return nil
}
Exemplo n.º 24
0
// InitTablet initializes the tablet record if necessary.
func (agent *ActionAgent) InitTablet(port, gRPCPort int32) error {
	// it should be either we have all three of init_keyspace,
	// init_shard and init_tablet_type, or none.
	if *initKeyspace == "" && *initShard == "" && *initTabletType == "" {
		// not initializing the record
		return nil
	}
	if *initKeyspace == "" || *initShard == "" || *initTabletType == "" {
		return fmt.Errorf("either need all of init_keyspace, init_shard and init_tablet_type, or none")
	}

	// parse init_tablet_type
	tabletType, err := topoproto.ParseTabletType(*initTabletType)
	if err != nil {
		return fmt.Errorf("invalid init_tablet_type %v: %v", *initTabletType, err)
	}
	if tabletType == topodatapb.TabletType_MASTER {
		// We disallow MASTER, so we don't have to change
		// shard.MasterAlias, and deal with the corner cases.
		return fmt.Errorf("init_tablet_type cannot be master, use replica instead")
	}

	// parse and validate shard name
	shard, _, err := topo.ValidateShardName(*initShard)
	if err != nil {
		return fmt.Errorf("cannot validate shard name %v: %v", *initShard, err)
	}

	// create a context for this whole operation
	ctx, cancel := context.WithTimeout(agent.batchCtx, *initTimeout)
	defer cancel()

	// read the shard, create it if necessary
	log.Infof("Reading shard record %v/%v", *initKeyspace, shard)
	si, err := agent.TopoServer.GetOrCreateShard(ctx, *initKeyspace, shard)
	if err != nil {
		return fmt.Errorf("InitTablet cannot GetOrCreateShard shard: %v", err)
	}
	if si.MasterAlias != nil && topoproto.TabletAliasEqual(si.MasterAlias, agent.TabletAlias) {
		// We're marked as master in the shard record, which could mean the master
		// tablet process was just restarted. However, we need to check if a new
		// master is in the process of taking over. In that case, it will let us
		// know by forcibly updating the old master's tablet record.
		oldTablet, err := agent.TopoServer.GetTablet(ctx, agent.TabletAlias)
		switch err {
		case topo.ErrNoNode:
			// There's no existing tablet record, so we can assume
			// no one has left us a message to step down.
			tabletType = topodatapb.TabletType_MASTER
		case nil:
			if oldTablet.Type == topodatapb.TabletType_MASTER {
				// We're marked as master in the shard record,
				// and our existing tablet record agrees.
				tabletType = topodatapb.TabletType_MASTER
			}
		default:
			return fmt.Errorf("InitTablet failed to read existing tablet record: %v", err)
		}
	}

	// See if we need to add the tablet's cell to the shard's cell list.
	if !si.HasCell(agent.TabletAlias.Cell) {
		si, err = agent.TopoServer.UpdateShardFields(ctx, *initKeyspace, shard, func(si *topo.ShardInfo) error {
			if si.HasCell(agent.TabletAlias.Cell) {
				// Someone else already did it.
				return topo.ErrNoUpdateNeeded
			}
			si.Cells = append(si.Cells, agent.TabletAlias.Cell)
			return nil
		})
		if err != nil {
			return fmt.Errorf("couldn't add tablet's cell to shard record: %v", err)
		}
	}
	log.Infof("Initializing the tablet for type %v", tabletType)

	// figure out the hostname
	hostname := *tabletHostname
	if hostname != "" {
		log.Infof("Using hostname: %v from -tablet_hostname flag.", hostname)
	} else {
		hostname, err := netutil.FullyQualifiedHostname()
		if err != nil {
			return err
		}
		log.Infof("Using detected machine hostname: %v To change this, fix your machine network configuration or override it with -tablet_hostname.", hostname)
	}

	// create and populate tablet record
	tablet := &topodatapb.Tablet{
		Alias:          agent.TabletAlias,
		Hostname:       hostname,
		PortMap:        make(map[string]int32),
		Keyspace:       *initKeyspace,
		Shard:          *initShard,
		Type:           tabletType,
		DbNameOverride: *initDbNameOverride,
		Tags:           initTags,
	}
	if port != 0 {
		tablet.PortMap["vt"] = port
	}
	if gRPCPort != 0 {
		tablet.PortMap["grpc"] = gRPCPort
	}
	if err := topo.TabletComplete(tablet); err != nil {
		return fmt.Errorf("InitTablet TabletComplete failed: %v", err)
	}

	// Now try to create the record (it will also fix up the
	// ShardReplication record if necessary).
	err = agent.TopoServer.CreateTablet(ctx, tablet)
	switch err {
	case nil:
		// It worked, we're good.
	case topo.ErrNodeExists:
		// The node already exists, will just try to update
		// it. So we read it first.
		oldTablet, err := agent.TopoServer.GetTablet(ctx, tablet.Alias)
		if err != nil {
			return fmt.Errorf("InitTablet failed to read existing tablet record: %v", err)
		}

		// Sanity check the keyspace and shard
		if oldTablet.Keyspace != tablet.Keyspace || oldTablet.Shard != tablet.Shard {
			return fmt.Errorf("InitTablet failed because existing tablet keyspace and shard %v/%v differ from the provided ones %v/%v", oldTablet.Keyspace, oldTablet.Shard, tablet.Keyspace, tablet.Shard)
		}

		// Then overwrite everything, ignoring version mismatch.
		if err := agent.TopoServer.UpdateTablet(ctx, topo.NewTabletInfo(tablet, -1)); err != nil {
			return fmt.Errorf("UpdateTablet failed: %v", err)
		}
	default:
		return fmt.Errorf("CreateTablet failed: %v", err)
	}

	return nil
}
Exemplo n.º 25
0
func (wr *Wrangler) initShardMasterLocked(ctx context.Context, ev *events.Reparent, keyspace, shard string, masterElectTabletAlias *topodatapb.TabletAlias, force bool, waitSlaveTimeout time.Duration) error {
	shardInfo, err := wr.ts.GetShard(ctx, keyspace, shard)
	if err != nil {
		return err
	}
	ev.ShardInfo = *shardInfo

	event.DispatchUpdate(ev, "reading tablet map")
	tabletMap, err := wr.ts.GetTabletMapForShard(ctx, keyspace, shard)
	if err != nil {
		return err
	}

	// Check the master elect is in tabletMap
	masterElectTabletInfo, ok := tabletMap[*masterElectTabletAlias]
	if !ok {
		return fmt.Errorf("master-elect tablet %v is not in the shard", topoproto.TabletAliasString(masterElectTabletAlias))
	}
	ev.NewMaster = *masterElectTabletInfo.Tablet

	// Check the master is the only master is the shard, or -force was used.
	_, masterTabletMap := topotools.SortedTabletMap(tabletMap)
	if !topoproto.TabletAliasEqual(shardInfo.MasterAlias, masterElectTabletAlias) {
		if !force {
			return fmt.Errorf("master-elect tablet %v is not the shard master, use -force to proceed anyway", topoproto.TabletAliasString(masterElectTabletAlias))
		}
		wr.logger.Warningf("master-elect tablet %v is not the shard master, proceeding anyway as -force was used", topoproto.TabletAliasString(masterElectTabletAlias))
	}
	if _, ok := masterTabletMap[*masterElectTabletAlias]; !ok {
		if !force {
			return fmt.Errorf("master-elect tablet %v is not a master in the shard, use -force to proceed anyway", topoproto.TabletAliasString(masterElectTabletAlias))
		}
		wr.logger.Warningf("master-elect tablet %v is not a master in the shard, proceeding anyway as -force was used", topoproto.TabletAliasString(masterElectTabletAlias))
	}
	haveOtherMaster := false
	for alias := range masterTabletMap {
		if !topoproto.TabletAliasEqual(&alias, masterElectTabletAlias) {
			haveOtherMaster = true
		}
	}
	if haveOtherMaster {
		if !force {
			return fmt.Errorf("master-elect tablet %v is not the only master in the shard, use -force to proceed anyway", topoproto.TabletAliasString(masterElectTabletAlias))
		}
		wr.logger.Warningf("master-elect tablet %v is not the only master in the shard, proceeding anyway as -force was used", topoproto.TabletAliasString(masterElectTabletAlias))
	}

	// First phase: reset replication on all tablets. If anyone fails,
	// we stop. It is probably because it is unreachable, and may leave
	// an unstable database process in the mix, with a database daemon
	// at a wrong replication spot.
	event.DispatchUpdate(ev, "resetting replication on all tablets")
	wg := sync.WaitGroup{}
	rec := concurrency.AllErrorRecorder{}
	for alias, tabletInfo := range tabletMap {
		wg.Add(1)
		go func(alias topodatapb.TabletAlias, tabletInfo *topo.TabletInfo) {
			defer wg.Done()
			wr.logger.Infof("resetting replication on tablet %v", topoproto.TabletAliasString(&alias))
			if err := wr.tmc.ResetReplication(ctx, tabletInfo.Tablet); err != nil {
				rec.RecordError(fmt.Errorf("Tablet %v ResetReplication failed (either fix it, or Scrap it): %v", topoproto.TabletAliasString(&alias), err))
			}
		}(alias, tabletInfo)
	}
	wg.Wait()
	if err := rec.Error(); err != nil {
		return err
	}

	// Tell the new master to break its slaves, return its replication
	// position
	wr.logger.Infof("initializing master on %v", topoproto.TabletAliasString(masterElectTabletAlias))
	event.DispatchUpdate(ev, "initializing master")
	rp, err := wr.tmc.InitMaster(ctx, masterElectTabletInfo.Tablet)
	if err != nil {
		return err
	}

	// Now tell the new master to insert the reparent_journal row,
	// and tell everybody else to become a slave of the new master,
	// and wait for the row in the reparent_journal table.
	// We start all these in parallel, to handle the semi-sync
	// case: for the master to be able to commit its row in the
	// reparent_journal table, it needs connected slaves.
	event.DispatchUpdate(ev, "reparenting all tablets")
	now := time.Now().UnixNano()
	wgMaster := sync.WaitGroup{}
	wgSlaves := sync.WaitGroup{}
	var masterErr error
	for alias, tabletInfo := range tabletMap {
		if topoproto.TabletAliasEqual(&alias, masterElectTabletAlias) {
			wgMaster.Add(1)
			go func(alias topodatapb.TabletAlias, tabletInfo *topo.TabletInfo) {
				defer wgMaster.Done()
				wr.logger.Infof("populating reparent journal on new master %v", topoproto.TabletAliasString(&alias))
				masterErr = wr.tmc.PopulateReparentJournal(ctx, tabletInfo.Tablet, now, initShardMasterOperation, &alias, rp)
			}(alias, tabletInfo)
		} else {
			wgSlaves.Add(1)
			go func(alias topodatapb.TabletAlias, tabletInfo *topo.TabletInfo) {
				defer wgSlaves.Done()
				wr.logger.Infof("initializing slave %v", topoproto.TabletAliasString(&alias))
				if err := wr.tmc.InitSlave(ctx, tabletInfo.Tablet, masterElectTabletAlias, rp, now); err != nil {
					rec.RecordError(fmt.Errorf("Tablet %v InitSlave failed: %v", topoproto.TabletAliasString(&alias), err))
				}
			}(alias, tabletInfo)
		}
	}

	// After the master is done, we can update the shard record
	// (note with semi-sync, it also means at least one slave is done)
	wgMaster.Wait()
	if masterErr != nil {
		wgSlaves.Wait()
		return fmt.Errorf("failed to PopulateReparentJournal on master: %v", masterErr)
	}
	if !topoproto.TabletAliasEqual(shardInfo.MasterAlias, masterElectTabletAlias) {
		if _, err := wr.ts.UpdateShardFields(ctx, keyspace, shard, func(si *topo.ShardInfo) error {
			si.MasterAlias = masterElectTabletAlias
			return nil
		}); err != nil {
			wgSlaves.Wait()
			return fmt.Errorf("failed to update shard master record: %v", err)
		}
	}

	// Wait for the slaves to complete. If some of them fail, we
	// don't want to rebuild the shard serving graph (the failure
	// will most likely be a timeout, and our context will be
	// expired, so the rebuild will fail anyway)
	wgSlaves.Wait()
	if err := rec.Error(); err != nil {
		return err
	}

	// Create database if necessary on the master. Slaves will get it too through
	// replication. Since the user called InitShardMaster, they've told us to
	// assume that whatever data is on all the slaves is what they intended.
	// If the database doesn't exist, it means the user intends for these tablets
	// to begin serving with no data (i.e. first time initialization).
	createDB := fmt.Sprintf("CREATE DATABASE IF NOT EXISTS `%s`", topoproto.TabletDbName(masterElectTabletInfo.Tablet))
	if _, err := wr.tmc.ExecuteFetchAsDba(ctx, masterElectTabletInfo.Tablet, false, []byte(createDB), 1, false, true); err != nil {
		return fmt.Errorf("failed to create database: %v", err)
	}

	return nil
}
Exemplo n.º 26
0
// TabletExternallyReparented updates all topo records so the current
// tablet is the new master for this shard.
// Should be called under RPCWrapLock.
func (agent *ActionAgent) TabletExternallyReparented(ctx context.Context, externalID string) error {
	startTime := time.Now()

	// If there is a finalize step running, wait for it to finish or time out
	// before checking the global shard record again.
	if agent.finalizeReparentCtx != nil {
		select {
		case <-agent.finalizeReparentCtx.Done():
			agent.finalizeReparentCtx = nil
		case <-ctx.Done():
			return ctx.Err()
		}
	}

	tablet := agent.Tablet()

	// Check the global shard record.
	si, err := agent.TopoServer.GetShard(ctx, tablet.Keyspace, tablet.Shard)
	if err != nil {
		log.Warningf("fastTabletExternallyReparented: failed to read global shard record for %v/%v: %v", tablet.Keyspace, tablet.Shard, err)
		return err
	}
	if topoproto.TabletAliasEqual(si.MasterAlias, tablet.Alias) {
		// We may get called on the current master even when nothing has changed.
		// If the global shard record is already updated, it means we successfully
		// finished a previous reparent to this tablet.
		return nil
	}

	// Remember when we were first told we're the master.
	// If another tablet claims to be master and offers a more recent time,
	// that tablet will be trusted over us.
	agent.mutex.Lock()
	agent._tabletExternallyReparentedTime = startTime
	agent._replicationDelay = 0
	agent.mutex.Unlock()

	// 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,
		},
		ExternalID: externalID,
	}
	defer func() {
		if err != nil {
			event.DispatchUpdate(ev, "failed: "+err.Error())
		}
	}()
	event.DispatchUpdate(ev, "starting external from tablet (fast)")

	var wg sync.WaitGroup
	var errs concurrency.AllErrorRecorder

	// Execute state change to master by force-updating only the local copy of the
	// tablet record. The actual record in topo will be updated later.
	log.Infof("fastTabletExternallyReparented: executing change callback for state change to MASTER")
	oldTablet := proto.Clone(tablet).(*topodatapb.Tablet)
	tablet.Type = topodatapb.TabletType_MASTER
	tablet.HealthMap = nil
	agent.setTablet(tablet)

	wg.Add(1)
	go func() {
		defer wg.Done()

		// This is where updateState will block for gracePeriod, while it gives
		// vtgate a chance to stop sending replica queries.
		if err := agent.updateState(ctx, oldTablet, "fastTabletExternallyReparented"); err != nil {
			errs.RecordError(fmt.Errorf("fastTabletExternallyReparented: failed to change tablet state to MASTER: %v", err))
		}
	}()

	wg.Add(1)
	go func() {
		defer wg.Done()

		// Directly write the new master endpoint in the serving graph.
		// We will do a true rebuild in the background soon, but in the meantime,
		// this will be enough for clients to re-resolve the new master.
		event.DispatchUpdate(ev, "writing new master endpoint")
		log.Infof("fastTabletExternallyReparented: writing new master endpoint to serving graph")
		ep, err := topo.TabletEndPoint(tablet)
		if err != nil {
			errs.RecordError(fmt.Errorf("fastTabletExternallyReparented: failed to generate EndPoint for tablet %v: %v", tablet.Alias, err))
			return
		}
		err = topo.UpdateEndPoints(ctx, agent.TopoServer, tablet.Alias.Cell,
			si.Keyspace(), si.ShardName(), topodatapb.TabletType_MASTER,
			&topodatapb.EndPoints{Entries: []*topodatapb.EndPoint{ep}}, -1)
		if err != nil {
			errs.RecordError(fmt.Errorf("fastTabletExternallyReparented: failed to update master endpoint: %v", err))
			return
		}
		externalReparentStats.Record("NewMasterVisible", startTime)
	}()

	// Wait for serving state grace period and serving graph update.
	wg.Wait()
	if errs.HasErrors() {
		return errs.Error()
	}

	// Start the finalize stage with a background context, but connect the trace.
	bgCtx, cancel := context.WithTimeout(agent.batchCtx, *finalizeReparentTimeout)
	bgCtx = trace.CopySpan(bgCtx, ctx)
	agent.finalizeReparentCtx = bgCtx
	go func() {
		err := agent.finalizeTabletExternallyReparented(bgCtx, si, ev)
		cancel()

		if err != nil {
			log.Warningf("finalizeTabletExternallyReparented error: %v", err)
			event.DispatchUpdate(ev, "failed: "+err.Error())
			return
		}
		externalReparentStats.Record("FullRebuild", startTime)
	}()

	return nil
}
Exemplo n.º 27
0
func TestShardReplicationStatuses(t *testing.T) {
	ctx := context.Background()
	ts := zktopo.NewTestServer(t, []string{"cell1", "cell2"})
	wr := wrangler.New(logutil.NewConsoleLogger(), ts, tmclient.NewTabletManagerClient(), time.Second)

	// create shard and tablets
	if err := ts.CreateShard(ctx, "test_keyspace", "0"); err != nil {
		t.Fatalf("CreateShard failed: %v", err)
	}
	master := NewFakeTablet(t, wr, "cell1", 1, pb.TabletType_MASTER)
	slave := NewFakeTablet(t, wr, "cell1", 2, pb.TabletType_REPLICA)

	// mark the master inside the shard
	si, err := ts.GetShard(ctx, "test_keyspace", "0")
	if err != nil {
		t.Fatalf("GetShard failed: %v", err)
	}
	si.MasterAlias = master.Tablet.Alias
	if err := ts.UpdateShard(ctx, si); err != nil {
		t.Fatalf("UpdateShard failed: %v", err)
	}

	// master action loop (to initialize host and port)
	master.FakeMysqlDaemon.CurrentMasterPosition = myproto.ReplicationPosition{
		GTIDSet: myproto.MariadbGTID{
			Domain:   5,
			Server:   456,
			Sequence: 892,
		},
	}
	master.StartActionLoop(t, wr)
	defer master.StopActionLoop(t)

	// slave loop
	slave.FakeMysqlDaemon.CurrentMasterPosition = myproto.ReplicationPosition{
		GTIDSet: myproto.MariadbGTID{
			Domain:   5,
			Server:   456,
			Sequence: 890,
		},
	}
	slave.FakeMysqlDaemon.CurrentMasterHost = master.Tablet.Hostname
	slave.FakeMysqlDaemon.CurrentMasterPort = int(master.Tablet.PortMap["mysql"])
	slave.StartActionLoop(t, wr)
	defer slave.StopActionLoop(t)

	// run ShardReplicationStatuses
	ti, rs, err := wr.ShardReplicationStatuses(ctx, "test_keyspace", "0")
	if err != nil {
		t.Fatalf("ShardReplicationStatuses failed: %v", err)
	}

	// check result (make master first in the array)
	if len(ti) != 2 || len(rs) != 2 {
		t.Fatalf("ShardReplicationStatuses returned wrong results: %v %v", ti, rs)
	}
	if topoproto.TabletAliasEqual(ti[0].Alias, slave.Tablet.Alias) {
		ti[0], ti[1] = ti[1], ti[0]
		rs[0], rs[1] = rs[1], rs[0]
	}
	if !topoproto.TabletAliasEqual(ti[0].Alias, master.Tablet.Alias) ||
		!topoproto.TabletAliasEqual(ti[1].Alias, slave.Tablet.Alias) ||
		rs[0].MasterHost != "" ||
		rs[1].MasterHost != master.Tablet.Hostname {
		t.Fatalf("ShardReplicationStatuses returend wrong results: %v %v", ti, rs)
	}
}
Exemplo n.º 28
0
func (wr *Wrangler) emergencyReparentShardLocked(ctx context.Context, ev *events.Reparent, keyspace, shard string, masterElectTabletAlias *pb.TabletAlias, waitSlaveTimeout time.Duration) error {
	shardInfo, err := wr.ts.GetShard(ctx, keyspace, shard)
	if err != nil {
		return err
	}
	ev.ShardInfo = *shardInfo

	event.DispatchUpdate(ev, "reading all tablets")
	tabletMap, err := wr.ts.GetTabletMapForShard(ctx, keyspace, shard)
	if err != nil {
		return err
	}

	// Check corner cases we're going to depend on
	masterElectTabletInfo, ok := tabletMap[*masterElectTabletAlias]
	if !ok {
		return fmt.Errorf("master-elect tablet %v is not in the shard", topoproto.TabletAliasString(masterElectTabletAlias))
	}
	ev.NewMaster = *masterElectTabletInfo.Tablet
	if topoproto.TabletAliasEqual(shardInfo.MasterAlias, masterElectTabletAlias) {
		return fmt.Errorf("master-elect tablet %v is already the master", topoproto.TabletAliasString(masterElectTabletAlias))
	}

	// Deal with the old master: try to remote-scrap it, if it's
	// truely dead we force-scrap it. Remove it from our map in any case.
	if shardInfo.HasMaster() {
		scrapOldMaster := true
		oldMasterTabletInfo, ok := tabletMap[*shardInfo.MasterAlias]
		if ok {
			delete(tabletMap, *shardInfo.MasterAlias)
		} else {
			oldMasterTabletInfo, err = wr.ts.GetTablet(ctx, shardInfo.MasterAlias)
			if err != nil {
				wr.logger.Warningf("cannot read old master tablet %v, won't touch it: %v", topoproto.TabletAliasString(shardInfo.MasterAlias), err)
				scrapOldMaster = false
			}
		}

		if scrapOldMaster {
			ev.OldMaster = *oldMasterTabletInfo.Tablet
			wr.logger.Infof("scrapping old master %v", topoproto.TabletAliasString(shardInfo.MasterAlias))

			ctx, cancel := context.WithTimeout(ctx, waitSlaveTimeout)
			defer cancel()

			if err := wr.tmc.Scrap(ctx, oldMasterTabletInfo); err != nil {
				wr.logger.Warningf("remote scrapping failed master failed, will force the scrap: %v", err)

				if err := topotools.Scrap(ctx, wr.ts, shardInfo.MasterAlias, true); err != nil {
					wr.logger.Warningf("old master topo scrapping failed, continuing anyway: %v", err)
				}
			}
		}
	}

	// Stop replication on all slaves, get their current
	// replication position
	event.DispatchUpdate(ev, "stop replication on all slaves")
	wg := sync.WaitGroup{}
	mu := sync.Mutex{}
	statusMap := make(map[pb.TabletAlias]myproto.ReplicationStatus)
	for alias, tabletInfo := range tabletMap {
		wg.Add(1)
		go func(alias pb.TabletAlias, tabletInfo *topo.TabletInfo) {
			defer wg.Done()
			wr.logger.Infof("getting replication position from %v", topoproto.TabletAliasString(&alias))
			ctx, cancel := context.WithTimeout(ctx, waitSlaveTimeout)
			defer cancel()
			rp, err := wr.TabletManagerClient().StopReplicationAndGetStatus(ctx, tabletInfo)
			if err != nil {
				wr.logger.Warningf("failed to get replication status from %v, ignoring tablet: %v", topoproto.TabletAliasString(&alias), err)
				return
			}
			mu.Lock()
			statusMap[alias] = rp
			mu.Unlock()
		}(alias, tabletInfo)
	}
	wg.Wait()

	// Verify masterElect is alive and has the most advanced position
	masterElectStatus, ok := statusMap[*masterElectTabletAlias]
	if !ok {
		return fmt.Errorf("couldn't get master elect %v replication position", topoproto.TabletAliasString(masterElectTabletAlias))
	}
	for alias, status := range statusMap {
		if topoproto.TabletAliasEqual(&alias, masterElectTabletAlias) {
			continue
		}
		if !masterElectStatus.Position.AtLeast(status.Position) {
			return fmt.Errorf("tablet %v is more advanced than master elect tablet %v: %v > %v", topoproto.TabletAliasString(&alias), topoproto.TabletAliasString(masterElectTabletAlias), status.Position, masterElectStatus)
		}
	}

	// Promote the masterElect
	wr.logger.Infof("promote slave %v", topoproto.TabletAliasString(masterElectTabletAlias))
	event.DispatchUpdate(ev, "promoting slave")
	rp, err := wr.tmc.PromoteSlave(ctx, masterElectTabletInfo)
	if err != nil {
		return fmt.Errorf("master-elect tablet %v failed to be upgraded to master: %v", topoproto.TabletAliasString(masterElectTabletAlias), err)
	}

	// Reset replication on all slaves to point to the new master, and
	// insert test row in the new master.
	// Go through all the tablets:
	// - new master: populate the reparent journal
	// - everybody else: reparent to new master, wait for row
	event.DispatchUpdate(ev, "reparenting all tablets")
	now := time.Now().UnixNano()
	wgMaster := sync.WaitGroup{}
	wgSlaves := sync.WaitGroup{}
	rec := concurrency.AllErrorRecorder{}
	var masterErr error
	for alias, tabletInfo := range tabletMap {
		if topoproto.TabletAliasEqual(&alias, masterElectTabletAlias) {
			wgMaster.Add(1)
			go func(alias pb.TabletAlias, tabletInfo *topo.TabletInfo) {
				defer wgMaster.Done()
				wr.logger.Infof("populating reparent journal on new master %v", topoproto.TabletAliasString(&alias))
				masterErr = wr.TabletManagerClient().PopulateReparentJournal(ctx, tabletInfo, now, emergencyReparentShardOperation, &alias, rp)
			}(alias, tabletInfo)
		} else {
			wgSlaves.Add(1)
			go func(alias pb.TabletAlias, tabletInfo *topo.TabletInfo) {
				defer wgSlaves.Done()
				wr.logger.Infof("setting new master on slave %v", topoproto.TabletAliasString(&alias))
				forceStartSlave := false
				if status, ok := statusMap[alias]; ok {
					forceStartSlave = status.SlaveIORunning || status.SlaveSQLRunning
				}
				if err := wr.TabletManagerClient().SetMaster(ctx, tabletInfo, masterElectTabletAlias, now, forceStartSlave); err != nil {
					rec.RecordError(fmt.Errorf("Tablet %v SetMaster failed: %v", topoproto.TabletAliasString(&alias), err))
				}
			}(alias, tabletInfo)
		}
	}

	// After the master is done, we can update the shard record
	// (note with semi-sync, it also means at least one slave is done)
	wgMaster.Wait()
	if masterErr != nil {
		wgSlaves.Wait()
		return fmt.Errorf("failed to PopulateReparentJournal on master: %v", masterErr)
	}
	wr.logger.Infof("updating shard record with new master %v", topoproto.TabletAliasString(masterElectTabletAlias))
	shardInfo.MasterAlias = masterElectTabletAlias
	if err := wr.ts.UpdateShard(ctx, shardInfo); err != nil {
		wgSlaves.Wait()
		return fmt.Errorf("failed to update shard master record: %v", err)
	}

	// Wait for the slaves to complete. If some of them fail, we
	// will rebuild the shard serving graph anyway
	wgSlaves.Wait()
	if err := rec.Error(); err != nil {
		wr.Logger().Errorf("Some slaves failed to reparent: %v", err)
		return err
	}

	// Then we rebuild the entire serving graph for the shard,
	// to account for all changes.
	wr.logger.Infof("rebuilding shard graph")
	event.DispatchUpdate(ev, "rebuilding shard serving graph")
	_, err = wr.RebuildShardGraph(ctx, keyspace, shard, nil)
	return err
}
Exemplo n.º 29
0
// InitTablet initializes the tablet record if necessary.
func (agent *ActionAgent) InitTablet(port, gRPCPort int32) error {
	// only enabled if one of init_tablet_type (when healthcheck
	// is disabled) or init_keyspace (when healthcheck is enabled)
	// is passed in, then check other parameters
	if *initTabletType == "" && *initKeyspace == "" {
		return nil
	}

	// figure out our default target type
	var tabletType topodatapb.TabletType
	if *initTabletType != "" {
		if *targetTabletType != "" {
			log.Fatalf("cannot specify both target_tablet_type and init_tablet_type parameters (as they might conflict)")
		}

		// use the type specified on the command line
		var err error
		tabletType, err = topoproto.ParseTabletType(*initTabletType)
		if err != nil {
			log.Fatalf("Invalid init tablet type %v: %v", *initTabletType, err)
		}

		if tabletType == topodatapb.TabletType_MASTER {
			// We disallow MASTER, so we don't have to change
			// shard.MasterAlias, and deal with the corner cases.
			log.Fatalf("init_tablet_type cannot be %v", tabletType)
		}

	} else if *targetTabletType != "" {
		if strings.ToUpper(*targetTabletType) == topodatapb.TabletType_name[int32(topodatapb.TabletType_MASTER)] {
			log.Fatalf("target_tablet_type cannot be '%v'. Use '%v' instead.", tabletType, topodatapb.TabletType_REPLICA)
		}

		// use spare, the healthcheck will turn us into what
		// we need to be eventually
		tabletType = topodatapb.TabletType_SPARE

	} else {
		log.Fatalf("if init tablet is enabled, one of init_tablet_type or target_tablet_type needs to be specified")
	}

	// create a context for this whole operation
	ctx, cancel := context.WithTimeout(agent.batchCtx, *initTimeout)
	defer cancel()

	// since we're assigned to a shard, make sure it exists, see if
	// we are its master, and update its cells list if necessary
	if *initKeyspace == "" || *initShard == "" {
		log.Fatalf("if init tablet is enabled and the target type is not idle, init_keyspace and init_shard also need to be specified")
	}
	shard, _, err := topo.ValidateShardName(*initShard)
	if err != nil {
		log.Fatalf("cannot validate shard name: %v", err)
	}

	log.Infof("Reading shard record %v/%v", *initKeyspace, shard)

	// read the shard, create it if necessary
	si, err := topotools.GetOrCreateShard(ctx, agent.TopoServer, *initKeyspace, shard)
	if err != nil {
		return fmt.Errorf("InitTablet cannot GetOrCreateShard shard: %v", err)
	}
	if si.MasterAlias != nil && topoproto.TabletAliasEqual(si.MasterAlias, agent.TabletAlias) {
		// we are the current master for this shard (probably
		// means the master tablet process was just restarted),
		// so InitTablet as master.
		tabletType = topodatapb.TabletType_MASTER
	}

	// See if we need to add the tablet's cell to the shard's cell
	// list.  If we do, it has to be under the shard lock.
	if !si.HasCell(agent.TabletAlias.Cell) {
		actionNode := actionnode.UpdateShard()
		lockPath, err := actionNode.LockShard(ctx, agent.TopoServer, *initKeyspace, shard)
		if err != nil {
			return fmt.Errorf("LockShard(%v/%v) failed: %v", *initKeyspace, shard, err)
		}

		// re-read the shard with the lock
		si, err = agent.TopoServer.GetShard(ctx, *initKeyspace, shard)
		if err != nil {
			return actionNode.UnlockShard(ctx, agent.TopoServer, *initKeyspace, shard, lockPath, err)
		}

		// see if we really need to update it now
		if !si.HasCell(agent.TabletAlias.Cell) {
			si.Cells = append(si.Cells, agent.TabletAlias.Cell)

			// write it back
			if err := agent.TopoServer.UpdateShard(ctx, si); err != nil {
				return actionNode.UnlockShard(ctx, agent.TopoServer, *initKeyspace, shard, lockPath, err)
			}
		}

		// and unlock
		if err := actionNode.UnlockShard(ctx, agent.TopoServer, *initKeyspace, shard, lockPath, nil); err != nil {
			return err
		}
	}
	log.Infof("Initializing the tablet for type %v", tabletType)

	// figure out the hostname
	hostname := *tabletHostname
	if hostname != "" {
		log.Infof("Using hostname: %v from -tablet_hostname flag.", hostname)
	} else {
		hostname, err := netutil.FullyQualifiedHostname()
		if err != nil {
			return err
		}
		log.Infof("Using detected machine hostname: %v To change this, fix your machine network configuration or override it with -tablet_hostname.", hostname)
	}

	// create and populate tablet record
	tablet := &topodatapb.Tablet{
		Alias:          agent.TabletAlias,
		Hostname:       hostname,
		PortMap:        make(map[string]int32),
		Keyspace:       *initKeyspace,
		Shard:          *initShard,
		Type:           tabletType,
		DbNameOverride: *initDbNameOverride,
		Tags:           initTags,
	}
	if port != 0 {
		tablet.PortMap["vt"] = port
	}
	if gRPCPort != 0 {
		tablet.PortMap["grpc"] = gRPCPort
	}
	if err := topo.TabletComplete(tablet); err != nil {
		return fmt.Errorf("InitTablet TabletComplete failed: %v", err)
	}

	// now try to create the record
	err = agent.TopoServer.CreateTablet(ctx, tablet)
	switch err {
	case nil:
		// it worked, we're good, can update the replication graph
		if err := topo.UpdateTabletReplicationData(ctx, agent.TopoServer, tablet); err != nil {
			return fmt.Errorf("UpdateTabletReplicationData failed: %v", err)
		}

	case topo.ErrNodeExists:
		// The node already exists, will just try to update
		// it. So we read it first.
		oldTablet, err := agent.TopoServer.GetTablet(ctx, tablet.Alias)
		if err != nil {
			return fmt.Errorf("InitTablet failed to read existing tablet record: %v", err)
		}

		// Sanity check the keyspace and shard
		if oldTablet.Keyspace != tablet.Keyspace || oldTablet.Shard != tablet.Shard {
			return fmt.Errorf("InitTablet failed because existing tablet keyspace and shard %v/%v differ from the provided ones %v/%v", oldTablet.Keyspace, oldTablet.Shard, tablet.Keyspace, tablet.Shard)
		}

		// And overwrite the rest
		*(oldTablet.Tablet) = *tablet
		if err := agent.TopoServer.UpdateTablet(ctx, oldTablet); err != nil {
			return fmt.Errorf("UpdateTablet failed: %v", err)
		}

		// Note we don't need to UpdateTabletReplicationData
		// as the tablet already existed with the right data
		// in the replication graph
	default:
		return fmt.Errorf("CreateTablet failed: %v", err)
	}

	// and now update the serving graph. Note we do that in any case,
	// to clean any inaccurate record from any part of the serving graph.
	if err := topotools.UpdateTabletEndpoints(ctx, agent.TopoServer, tablet); err != nil {
		return fmt.Errorf("UpdateTabletEndpoints failed: %v", err)
	}

	return nil
}
Exemplo n.º 30
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// TabletExternallyReparented updates all topo records so the current
// tablet is the new master for this shard.
func (agent *ActionAgent) TabletExternallyReparented(ctx context.Context, externalID string) error {
	if err := agent.lock(ctx); err != nil {
		return err
	}
	defer agent.unlock()

	startTime := time.Now()

	// If there is a finalize step running, wait for it to finish or time out
	// before checking the global shard record again.
	if agent.finalizeReparentCtx != nil {
		select {
		case <-agent.finalizeReparentCtx.Done():
			agent.finalizeReparentCtx = nil
		case <-ctx.Done():
			return ctx.Err()
		}
	}

	tablet := agent.Tablet()

	// Check the global shard record.
	si, err := agent.TopoServer.GetShard(ctx, tablet.Keyspace, tablet.Shard)
	if err != nil {
		log.Warningf("fastTabletExternallyReparented: failed to read global shard record for %v/%v: %v", tablet.Keyspace, tablet.Shard, err)
		return err
	}
	if topoproto.TabletAliasEqual(si.MasterAlias, tablet.Alias) {
		// We may get called on the current master even when nothing has changed.
		// If the global shard record is already updated, it means we successfully
		// finished a previous reparent to this tablet.
		return nil
	}

	// Remember when we were first told we're the master.
	// If another tablet claims to be master and offers a more recent time,
	// that tablet will be trusted over us.
	agent.mutex.Lock()
	agent._tabletExternallyReparentedTime = startTime
	agent._replicationDelay = 0
	agent.mutex.Unlock()

	// 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,
		},
		ExternalID: externalID,
	}
	defer func() {
		if err != nil {
			event.DispatchUpdate(ev, "failed: "+err.Error())
		}
	}()
	event.DispatchUpdate(ev, "starting external from tablet (fast)")

	// Execute state change to master by force-updating only the local copy of the
	// tablet record. The actual record in topo will be updated later.
	log.Infof("fastTabletExternallyReparented: executing change callback for state change to MASTER")
	oldTablet := proto.Clone(tablet).(*topodatapb.Tablet)
	tablet.Type = topodatapb.TabletType_MASTER
	agent.setTablet(tablet)

	// This is where updateState will block for gracePeriod, while it gives
	// vtgate a chance to stop sending replica queries.
	agent.updateState(ctx, oldTablet, "fastTabletExternallyReparented")

	// Start the finalize stage with a background context, but connect the trace.
	bgCtx, cancel := context.WithTimeout(agent.batchCtx, *finalizeReparentTimeout)
	bgCtx = trace.CopySpan(bgCtx, ctx)
	agent.finalizeReparentCtx = bgCtx
	go func() {
		err := agent.finalizeTabletExternallyReparented(bgCtx, si, ev)
		cancel()

		if err != nil {
			log.Warningf("finalizeTabletExternallyReparented error: %v", err)
			event.DispatchUpdate(ev, "failed: "+err.Error())
			return
		}
		externalReparentStats.Record("FullRebuild", startTime)
	}()

	return nil
}