Golang Server.GetKnownCells方法代码示例

// GetAllTabletsAccrossCells returns all tablets from known cells.
func GetAllTabletsAccrossCells(ts topo.Server) ([]*topo.TabletInfo, error) {
	cells, err := ts.GetKnownCells()
	if err != nil {
		return nil, err
	}

	results := make(chan []*topo.TabletInfo)
	errors := make(chan error)
	for _, cell := range cells {
		go func(cell string) {
			tablets, err := GetAllTablets(ts, cell)
			if err != nil && err != topo.ErrNoNode {
				errors <- err
				return
			}
			results <- tablets
		}(cell)
	}

	allTablets := make([]*topo.TabletInfo, 0)
	for _ = range cells {
		select {
		case tablets := <-results:
			allTablets = append(allTablets, tablets...)
		case err := <-errors:
			return nil, err
		}
	}
	return allTablets, nil
}

// GetAllTabletsAcrossCells returns all tablets from known cells.
// If it returns topo.ErrPartialResult, then the list is valid, but partial.
func GetAllTabletsAcrossCells(ctx context.Context, ts topo.Server) ([]*topo.TabletInfo, error) {
	cells, err := ts.GetKnownCells(ctx)
	if err != nil {
		return nil, err
	}

	results := make([][]*topo.TabletInfo, len(cells))
	errors := make([]error, len(cells))
	wg := sync.WaitGroup{}
	wg.Add(len(cells))
	for i, cell := range cells {
		go func(i int, cell string) {
			results[i], errors[i] = GetAllTablets(ctx, ts, cell)
			wg.Done()
		}(i, cell)
	}
	wg.Wait()

	err = nil
	var allTablets []*topo.TabletInfo
	for i := range cells {
		if errors[i] == nil {
			allTablets = append(allTablets, results[i]...)
		} else {
			err = topo.ErrPartialResult
		}
	}
	return allTablets, err
}

// CopyTablets will create the tablets in the destination topo
func CopyTablets(fromTS, toTS topo.Server) {
	cells, err := fromTS.GetKnownCells()
	if err != nil {
		log.Fatalf("fromTS.GetKnownCells failed: %v", err)
	}

	wg := sync.WaitGroup{}
	rec := concurrency.AllErrorRecorder{}
	for _, cell := range cells {
		wg.Add(1)
		go func(cell string) {
			defer wg.Done()
			tabletAliases, err := fromTS.GetTabletsByCell(cell)
			if err != nil {
				rec.RecordError(err)
			} else {
				for _, tabletAlias := range tabletAliases {
					wg.Add(1)
					go func(tabletAlias topo.TabletAlias) {
						defer wg.Done()

						// read the source tablet
						ti, err := fromTS.GetTablet(tabletAlias)
						if err != nil {
							rec.RecordError(err)
							return
						}

						// try to create the destination
						err = toTS.CreateTablet(ti.Tablet)
						if err == topo.ErrNodeExists {
							// update the destination tablet
							log.Warningf("tablet %v already exists, updating it", tabletAlias)
							err = toTS.UpdateTabletFields(ti.Alias(), func(t *topo.Tablet) error {
								*t = *ti.Tablet
								return nil
							})
						}
						if err != nil {
							rec.RecordError(err)
							return
						}

						// create the replication paths
						// for masters only here
						if ti.Type == topo.TYPE_MASTER {
							if err = toTS.CreateReplicationPath(ti.Keyspace, ti.Shard, ti.Alias().String()); err != nil && err != topo.ErrNodeExists {
								rec.RecordError(err)
							}
						}
					}(tabletAlias)
				}
			}
		}(cell)
	}
	wg.Wait()
	if rec.HasErrors() {
		log.Fatalf("copyTablets failed: %v", rec.Error())
	}
}

func newRealtimeStats(ts topo.Server) (*realtimeStats, error) {
	hc := discovery.NewHealthCheck(*vtctl.HealthCheckTimeout, *vtctl.HealthcheckRetryDelay, *vtctl.HealthCheckTimeout)
	tabletStatsCache := &tabletStatsCache{
		statuses: make(map[string]map[string]*discovery.TabletStats),
	}
	hc.SetListener(tabletStatsCache)
	r := &realtimeStats{
		healthCheck: hc,
		tabletStats: tabletStatsCache,
	}

	// Get the list of all tablets from all cells and monitor the topology for added or removed tablets with a CellTabletsWatcher.
	cells, err := ts.GetKnownCells(context.Background())
	if err != nil {
		return r, fmt.Errorf("error when getting cells: %v", err)
	}
	var watchers []*discovery.TopologyWatcher
	for _, cell := range cells {
		watcher := discovery.NewCellTabletsWatcher(ts, hc, cell, *vtctl.HealthCheckTopologyRefresh, discovery.DefaultTopoReadConcurrency)
		watchers = append(watchers, watcher)
	}
	r.cellWatchers = watchers

	return r, nil
}

func getLocalCell(ctx context.Context, t *testing.T, ts topo.Server) string {
	cells, err := ts.GetKnownCells(ctx)
	if err != nil {
		t.Fatalf("GetKnownCells: %v", err)
	}
	if len(cells) < 1 {
		t.Fatalf("provided topo.Server doesn't have enough cells (need at least 1): %v", cells)
	}
	return cells[0]
}

func newKnownCellsCache(ts topo.Server) *VersionedObjectCache {
	return NewVersionedObjectCache(func(ctx context.Context) (VersionedObject, error) {
		cells, err := ts.GetKnownCells(ctx)
		if err != nil {
			return nil, err
		}
		return &KnownCells{
			Cells: cells,
		}, nil
	})
}

// CopyTablets will create the tablets in the destination topo
func CopyTablets(fromTS, toTS topo.Server) {
	cells, err := fromTS.GetKnownCells()
	if err != nil {
		log.Fatalf("fromTS.GetKnownCells: %v", err)
	}

	wg := sync.WaitGroup{}
	rec := concurrency.AllErrorRecorder{}
	for _, cell := range cells {
		wg.Add(1)
		go func(cell string) {
			defer wg.Done()
			tabletAliases, err := fromTS.GetTabletsByCell(cell)
			if err != nil {
				rec.RecordError(fmt.Errorf("GetTabletsByCell(%v): %v", cell, err))
			} else {
				for _, tabletAlias := range tabletAliases {
					wg.Add(1)
					go func(tabletAlias topo.TabletAlias) {
						defer wg.Done()

						// read the source tablet
						ti, err := fromTS.GetTablet(tabletAlias)
						if err != nil {
							rec.RecordError(fmt.Errorf("GetTablet(%v): %v", tabletAlias, err))
							return
						}

						// try to create the destination
						err = toTS.CreateTablet(ti.Tablet)
						if err == topo.ErrNodeExists {
							// update the destination tablet
							log.Warningf("tablet %v already exists, updating it", tabletAlias)
							err = toTS.UpdateTabletFields(ti.Alias, func(t *topo.Tablet) error {
								*t = *ti.Tablet
								return nil
							})
						}
						if err != nil {
							rec.RecordError(fmt.Errorf("CreateTablet(%v): %v", tabletAlias, err))
							return
						}
					}(tabletAlias)
				}
			}
		}(cell)
	}
	wg.Wait()
	if rec.HasErrors() {
		log.Fatalf("copyTablets failed: %v", rec.Error())
	}
}

func initAPI(ctx context.Context, ts topo.Server, actions *ActionRepository) {
	tabletHealthCache := newTabletHealthCache(ts)

	// Cells
	handleCollection("cells", func(r *http.Request) (interface{}, error) {
		if getItemPath(r.URL.Path) != "" {
			return nil, errors.New("cells can only be listed, not retrieved")
		}
		return ts.GetKnownCells(ctx)
	})

	// Keyspaces
	handleCollection("keyspaces", func(r *http.Request) (interface{}, error) {
		keyspace := getItemPath(r.URL.Path)

		// List all keyspaces.
		if keyspace == "" {
			return ts.GetKeyspaces(ctx)
		}

		// Perform an action on a keyspace.
		if r.Method == "POST" {
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			action := r.FormValue("action")
			if action == "" {
				return nil, errors.New("must specify action")
			}
			return actions.ApplyKeyspaceAction(ctx, action, keyspace, r), nil
		}

		// Get the keyspace record.
		return ts.GetKeyspace(ctx, keyspace)
	})

	// Shards
	handleCollection("shards", func(r *http.Request) (interface{}, error) {
		shardPath := getItemPath(r.URL.Path)
		if !strings.Contains(shardPath, "/") {
			return nil, fmt.Errorf("invalid shard path: %q", shardPath)
		}
		parts := strings.SplitN(shardPath, "/", 2)
		keyspace := parts[0]
		shard := parts[1]

		// List the shards in a keyspace.
		if shard == "" {
			return ts.GetShardNames(ctx, keyspace)
		}

		// Perform an action on a shard.
		if r.Method == "POST" {
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			action := r.FormValue("action")
			if action == "" {
				return nil, errors.New("must specify action")
			}
			return actions.ApplyShardAction(ctx, action, keyspace, shard, r), nil
		}

		// Get the shard record.
		return ts.GetShard(ctx, keyspace, shard)
	})

	// Tablets
	handleCollection("tablets", func(r *http.Request) (interface{}, error) {
		tabletPath := getItemPath(r.URL.Path)

		// List tablets based on query params.
		if tabletPath == "" {
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			shardRef := r.FormValue("shard")
			cell := r.FormValue("cell")

			if shardRef != "" {
				// Look up by keyspace/shard, and optionally cell.
				keyspace, shard, err := topoproto.ParseKeyspaceShard(shardRef)
				if err != nil {
					return nil, err
				}
				if cell != "" {
					return ts.FindAllTabletAliasesInShardByCell(ctx, keyspace, shard, []string{cell})
				}
				return ts.FindAllTabletAliasesInShard(ctx, keyspace, shard)
			}

			// Get all tablets in a cell.
			if cell == "" {
				return nil, errors.New("cell param required")
			}
			return ts.GetTabletsByCell(ctx, cell)
		}

		// Get tablet health.
		if parts := strings.Split(tabletPath, "/"); len(parts) == 2 && parts[1] == "health" {
//.........这里部分代码省略.........

func initAPI(ctx context.Context, ts topo.Server, actions *ActionRepository) {
	tabletHealthCache := newTabletHealthCache(ts)

	// Cells
	handleCollection("cells", func(r *http.Request) (interface{}, error) {
		if getItemPath(r.URL.Path) != "" {
			return nil, errors.New("cells can only be listed, not retrieved")
		}
		return ts.GetKnownCells(ctx)
	})

	// Keyspaces
	handleCollection("keyspaces", func(r *http.Request) (interface{}, error) {
		keyspace := getItemPath(r.URL.Path)

		// List all keyspaces.
		if keyspace == "" {
			return ts.GetKeyspaces(ctx)
		}

		// Perform an action on a keyspace.
		if r.Method == "POST" {
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			action := r.FormValue("action")
			if action == "" {
				return nil, errors.New("must specify action")
			}
			return actions.ApplyKeyspaceAction(ctx, action, keyspace, r), nil
		}

		// Get the keyspace record.
		return ts.GetKeyspace(ctx, keyspace)
	})

	// Shards
	handleCollection("shards", func(r *http.Request) (interface{}, error) {
		shardPath := getItemPath(r.URL.Path)
		if !strings.Contains(shardPath, "/") {
			return nil, fmt.Errorf("invalid shard path: %q", shardPath)
		}
		parts := strings.SplitN(shardPath, "/", 2)
		keyspace := parts[0]
		shard := parts[1]

		// List the shards in a keyspace.
		if shard == "" {
			return ts.GetShardNames(ctx, keyspace)
		}

		// Perform an action on a shard.
		if r.Method == "POST" {
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			action := r.FormValue("action")
			if action == "" {
				return nil, errors.New("must specify action")
			}
			return actions.ApplyShardAction(ctx, action, keyspace, shard, r), nil
		}

		// Get the shard record.
		return ts.GetShard(ctx, keyspace, shard)
	})

	// Tablets
	handleCollection("tablets", func(r *http.Request) (interface{}, error) {
		tabletPath := getItemPath(r.URL.Path)

		// List tablets based on query params.
		if tabletPath == "" {
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			shardRef := r.FormValue("shard")
			cell := r.FormValue("cell")

			if shardRef != "" {
				// Look up by keyspace/shard, and optionally cell.
				keyspace, shard, err := topoproto.ParseKeyspaceShard(shardRef)
				if err != nil {
					return nil, err
				}
				if cell != "" {
					return ts.FindAllTabletAliasesInShardByCell(ctx, keyspace, shard, []string{cell})
				}
				return ts.FindAllTabletAliasesInShard(ctx, keyspace, shard)
			}

			// Get all tablets in a cell.
			if cell == "" {
				return nil, errors.New("cell param required")
			}
			return ts.GetTabletsByCell(ctx, cell)
		}

		// Get tablet health.
		if parts := strings.Split(tabletPath, "/"); len(parts) == 2 && parts[1] == "health" {
//.........这里部分代码省略.........

func initAPI(ctx context.Context, ts topo.Server, actions *ActionRepository, realtimeStats *realtimeStats) {
	tabletHealthCache := newTabletHealthCache(ts)
	tmClient := tmclient.NewTabletManagerClient()

	// Cells
	handleCollection("cells", func(r *http.Request) (interface{}, error) {
		if getItemPath(r.URL.Path) != "" {
			return nil, errors.New("cells can only be listed, not retrieved")
		}
		return ts.GetKnownCells(ctx)
	})

	// Keyspaces
	handleCollection("keyspaces", func(r *http.Request) (interface{}, error) {
		keyspace := getItemPath(r.URL.Path)
		switch r.Method {
		case "GET":
			// List all keyspaces.
			if keyspace == "" {
				return ts.GetKeyspaces(ctx)
			}
			// Get the keyspace record.
			k, err := ts.GetKeyspace(ctx, keyspace)
			// Pass the embedded proto directly or jsonpb will panic.
			return k.Keyspace, err
			// Perform an action on a keyspace.
		case "POST":
			if keyspace == "" {
				return nil, errors.New("A POST request needs a keyspace in the URL")
			}
			if err := r.ParseForm(); err != nil {
				return nil, err
			}

			action := r.FormValue("action")
			if action == "" {
				return nil, errors.New("A POST request must specify action")
			}
			return actions.ApplyKeyspaceAction(ctx, action, keyspace, r), nil
		default:
			return nil, fmt.Errorf("unsupported HTTP method: %v", r.Method)
		}
	})

	// Shards
	handleCollection("shards", func(r *http.Request) (interface{}, error) {
		shardPath := getItemPath(r.URL.Path)
		if !strings.Contains(shardPath, "/") {
			return nil, fmt.Errorf("invalid shard path: %q", shardPath)
		}
		parts := strings.SplitN(shardPath, "/", 2)
		keyspace := parts[0]
		shard := parts[1]

		// List the shards in a keyspace.
		if shard == "" {
			return ts.GetShardNames(ctx, keyspace)
		}

		// Perform an action on a shard.
		if r.Method == "POST" {
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			action := r.FormValue("action")
			if action == "" {
				return nil, errors.New("must specify action")
			}
			return actions.ApplyShardAction(ctx, action, keyspace, shard, r), nil
		}

		// Get the shard record.
		si, err := ts.GetShard(ctx, keyspace, shard)
		// Pass the embedded proto directly or jsonpb will panic.
		return si.Shard, err
	})

	// SrvKeyspace
	handleCollection("srv_keyspace", func(r *http.Request) (interface{}, error) {
		keyspacePath := getItemPath(r.URL.Path)
		parts := strings.SplitN(keyspacePath, "/", 2)

		// Request was incorrectly formatted.
		if len(parts) != 2 {
			return nil, fmt.Errorf("invalid srvkeyspace path: %q  expected path: /srv_keyspace/<cell>/<keyspace>", keyspacePath)
		}

		cell := parts[0]
		keyspace := parts[1]

		if cell == "local" {
			if *localCell == "" {
				return nil, fmt.Errorf("local cell requested, but not specified. Please set with -cell flag")
			}
			cell = *localCell
		}

		// If a keyspace is provided then return the specified srvkeyspace.
		if keyspace != "" {
			srvKeyspace, err := ts.GetSrvKeyspace(ctx, cell, keyspace)
//.........这里部分代码省略.........

func initAPI(ctx context.Context, ts topo.Server) {
	// Get Cells
	handleGet("cells", func(r *http.Request) (interface{}, error) {
		if getItemPath(r.URL.Path) != "" {
			return nil, errors.New("cells can only be listed, not retrieved")
		}
		return ts.GetKnownCells(ctx)
	})

	// Get Keyspaces
	handleGet("keyspaces", func(r *http.Request) (interface{}, error) {
		keyspace := getItemPath(r.URL.Path)
		if keyspace == "" {
			return ts.GetKeyspaces(ctx)
		}
		return ts.GetKeyspace(ctx, keyspace)
	})

	// Get Shards
	handleGet("shards", func(r *http.Request) (interface{}, error) {
		shardPath := getItemPath(r.URL.Path)
		if !strings.Contains(shardPath, "/") {
			return nil, fmt.Errorf("invalid shard path: %q", shardPath)
		}
		parts := strings.SplitN(shardPath, "/", 2)
		if parts[1] == "" {
			// It's just a keyspace. List the shards.
			return ts.GetShardNames(ctx, parts[0])
		}
		// It's a keyspace/shard reference.
		return ts.GetShard(ctx, parts[0], parts[1])
	})

	// Get Tablets
	handleGet("tablets", func(r *http.Request) (interface{}, error) {
		tabletPath := getItemPath(r.URL.Path)
		if tabletPath == "" {
			// List tablets based on query params.
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			shardRef := r.FormValue("shard")
			cell := r.FormValue("cell")

			if shardRef != "" {
				// Look up by keyspace/shard, and optionally cell.
				keyspace, shard, err := topo.ParseKeyspaceShardString(shardRef)
				if err != nil {
					return nil, err
				}
				if cell != "" {
					return topo.FindAllTabletAliasesInShardByCell(ctx, ts, keyspace, shard, []string{cell})
				}
				return topo.FindAllTabletAliasesInShard(ctx, ts, keyspace, shard)
			}

			// Get all tablets in a cell.
			if cell == "" {
				return nil, errors.New("cell param required")
			}
			return ts.GetTabletsByCell(ctx, cell)
		}

		// Get a specific tablet.
		tabletAlias, err := topo.ParseTabletAliasString(tabletPath)
		if err != nil {
			return nil, err
		}
		return ts.GetTablet(ctx, tabletAlias)
	})

	// Get EndPoints
	handleGet("endpoints", func(r *http.Request) (interface{}, error) {
		// We expect cell/keyspace/shard/tabletType.
		epPath := getItemPath(r.URL.Path)
		parts := strings.Split(epPath, "/")
		if len(parts) != 4 {
			return nil, fmt.Errorf("invalid cell/keyspace/shard/tabletType: %q", epPath)
		}

		if parts[3] == "" {
			// tabletType is empty, so list the tablet types.
			return ts.GetSrvTabletTypesPerShard(ctx, parts[0], parts[1], parts[2])
		}

		// Get the endpoints object for a specific type.
		ep, _, err := ts.GetEndPoints(ctx, parts[0], parts[1], parts[2], topo.TabletType(parts[3]))
		return ep, err
	})
}

func initAPI(ctx context.Context, ts topo.Server, actions *ActionRepository) {
	tabletHealthCache := newTabletHealthCache(ts)
	tmClient := tmclient.NewTabletManagerClient()

	// Cells
	handleCollection("cells", func(r *http.Request) (interface{}, error) {
		if getItemPath(r.URL.Path) != "" {
			return nil, errors.New("cells can only be listed, not retrieved")
		}
		return ts.GetKnownCells(ctx)
	})

	// Keyspaces
	handleCollection("keyspaces", func(r *http.Request) (interface{}, error) {
		keyspace := getItemPath(r.URL.Path)

		// List all keyspaces.
		if keyspace == "" {
			return ts.GetKeyspaces(ctx)
		}

		// Perform an action on a keyspace.
		if r.Method == "POST" {
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			action := r.FormValue("action")
			if action == "" {
				return nil, errors.New("must specify action")
			}
			return actions.ApplyKeyspaceAction(ctx, action, keyspace, r), nil
		}

		// Get the keyspace record.
		return ts.GetKeyspace(ctx, keyspace)
	})

	// Shards
	handleCollection("shards", func(r *http.Request) (interface{}, error) {
		shardPath := getItemPath(r.URL.Path)
		if !strings.Contains(shardPath, "/") {
			return nil, fmt.Errorf("invalid shard path: %q", shardPath)
		}
		parts := strings.SplitN(shardPath, "/", 2)
		keyspace := parts[0]
		shard := parts[1]

		// List the shards in a keyspace.
		if shard == "" {
			return ts.GetShardNames(ctx, keyspace)
		}

		// Perform an action on a shard.
		if r.Method == "POST" {
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			action := r.FormValue("action")
			if action == "" {
				return nil, errors.New("must specify action")
			}
			return actions.ApplyShardAction(ctx, action, keyspace, shard, r), nil
		}

		// Get the shard record.
		return ts.GetShard(ctx, keyspace, shard)
	})
	//SrvKeyspace
	handleCollection("srv_keyspace", func(r *http.Request) (interface{}, error) {
		keyspacePath := getItemPath(r.URL.Path)
		parts := strings.SplitN(keyspacePath, "/", 2)

		//request was incorrectly formatted
		if len(parts) != 2 {
			return nil, fmt.Errorf("invalid srvkeyspace path: %q  expected path: /srv_keyspace/<cell>/<keyspace>", keyspacePath)
		}

		cell := parts[0]
		keyspace := parts[1]

		if cell == "local" {
			if *localCell == "" {
				return nil, fmt.Errorf("local cell requested, but not specified. Please set with -cell flag")
			}
			cell = *localCell
		}

		//If a keyspace is provided then return the specified srvkeyspace
		if keyspace != "" {
			srvKeyspace, err := ts.GetSrvKeyspace(ctx, cell, keyspace)
			if err != nil {
				return nil, fmt.Errorf("Can't get server keyspace: %v", err)
			}
			return srvKeyspace, nil
		}

		//Else return the srvKeyspace from all keyspaces
		srvKeyspaces := make(map[string]interface{})
		keyspaceNamesList, err := ts.GetSrvKeyspaceNames(ctx, cell)
		if err != nil {
//.........这里部分代码省略.........

func initAPI(ctx context.Context, ts topo.Server, actions *ActionRepository) {
	tabletHealthCache := newTabletHealthCache(ts)

	// Cells
	handleCollection("cells", func(r *http.Request) (interface{}, error) {
		if getItemPath(r.URL.Path) != "" {
			return nil, errors.New("cells can only be listed, not retrieved")
		}
		return ts.GetKnownCells(ctx)
	})

	// Keyspaces
	handleCollection("keyspaces", func(r *http.Request) (interface{}, error) {
		keyspace := getItemPath(r.URL.Path)

		// List all keyspaces.
		if keyspace == "" {
			return ts.GetKeyspaces(ctx)
		}

		// Perform an action on a keyspace.
		if r.Method == "POST" {
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			action := r.FormValue("action")
			if action == "" {
				return nil, errors.New("must specify action")
			}
			return actions.ApplyKeyspaceAction(ctx, action, keyspace, r), nil
		}

		// Get the keyspace record.
		return ts.GetKeyspace(ctx, keyspace)
	})

	// Shards
	handleCollection("shards", func(r *http.Request) (interface{}, error) {
		shardPath := getItemPath(r.URL.Path)
		if !strings.Contains(shardPath, "/") {
			return nil, fmt.Errorf("invalid shard path: %q", shardPath)
		}
		parts := strings.SplitN(shardPath, "/", 2)
		keyspace := parts[0]
		shard := parts[1]

		// List the shards in a keyspace.
		if shard == "" {
			return ts.GetShardNames(ctx, keyspace)
		}

		// Perform an action on a shard.
		if r.Method == "POST" {
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			action := r.FormValue("action")
			if action == "" {
				return nil, errors.New("must specify action")
			}
			return actions.ApplyShardAction(ctx, action, keyspace, shard, r), nil
		}

		// Get the shard record.
		return ts.GetShard(ctx, keyspace, shard)
	})

	// Tablets
	handleCollection("tablets", func(r *http.Request) (interface{}, error) {
		tabletPath := getItemPath(r.URL.Path)

		// List tablets based on query params.
		if tabletPath == "" {
			if err := r.ParseForm(); err != nil {
				return nil, err
			}
			shardRef := r.FormValue("shard")
			cell := r.FormValue("cell")

			if shardRef != "" {
				// Look up by keyspace/shard, and optionally cell.
				keyspace, shard, err := topo.ParseKeyspaceShardString(shardRef)
				if err != nil {
					return nil, err
				}
				if cell != "" {
					return topo.FindAllTabletAliasesInShardByCell(ctx, ts, keyspace, shard, []string{cell})
				}
				return topo.FindAllTabletAliasesInShard(ctx, ts, keyspace, shard)
			}

			// Get all tablets in a cell.
			if cell == "" {
				return nil, errors.New("cell param required")
			}
			return ts.GetTabletsByCell(ctx, cell)
		}

		// Get tablet health.
		if parts := strings.Split(tabletPath, "/"); len(parts) == 2 && parts[1] == "health" {
//.........这里部分代码省略.........

// RebuildVSchema rebuilds the SrvVSchema for the provided cell list
// (or all cells if cell list is empty).
func RebuildVSchema(ctx context.Context, log logutil.Logger, ts topo.Server, cells []string) error {
	// get the actual list of cells
	if len(cells) == 0 {
		var err error
		cells, err = ts.GetKnownCells(ctx)
		if err != nil {
			return fmt.Errorf("GetKnownCells failed: %v", err)
		}
	}

	// get the keyspaces
	keyspaces, err := ts.GetKeyspaces(ctx)
	if err != nil {
		return fmt.Errorf("GetKeyspaces failed: %v", err)
	}

	// build the SrvVSchema in parallel, protected by mu
	wg := sync.WaitGroup{}
	mu := sync.Mutex{}
	var finalErr error
	srvVSchema := &vschemapb.SrvVSchema{
		Keyspaces: map[string]*vschemapb.Keyspace{},
	}
	for _, keyspace := range keyspaces {
		wg.Add(1)
		go func(keyspace string) {
			defer wg.Done()

			k, err := ts.GetVSchema(ctx, keyspace)
			if err == topo.ErrNoNode {
				err = nil
				k = &vschemapb.Keyspace{}
			}

			mu.Lock()
			defer mu.Unlock()
			if err != nil {
				log.Errorf("GetVSchema(%v) failed: %v", keyspace, err)
				finalErr = err
				return
			}
			srvVSchema.Keyspaces[keyspace] = k
		}(keyspace)
	}
	wg.Wait()
	if finalErr != nil {
		return finalErr
	}

	// now save the SrvVSchema in all cells in parallel
	for _, cell := range cells {
		wg.Add(1)
		go func(cell string) {
			defer wg.Done()
			if err := ts.UpdateSrvVSchema(ctx, cell, srvVSchema); err != nil {
				log.Errorf("UpdateSrvVSchema(%v) failed: %v", cell, err)
				mu.Lock()
				finalErr = err
				mu.Unlock()
			}
		}(cell)
	}
	wg.Wait()

	return finalErr
}