// DoRPC acts as a switchboard for RPC commands.
func (d *Data) DoRPC(req datastore.Request, reply *datastore.Response) error {
	switch req.TypeCommand() {
	case "load":
		if len(req.Command) < 5 {
			return fmt.Errorf("Poorly formatted load command.  See command-line help.")
		}
		// Parse the request
		var uuidStr, dataName, cmdStr, offsetStr string
		filenames, err := req.FilenameArgs(1, &uuidStr, &dataName, &cmdStr, &offsetStr)
		if err != nil {
			return err
		}
		if len(filenames) == 0 {
			return fmt.Errorf("Need to include at least one file to add: %s", req)
		}

		// Get offset
		offset, err := dvid.StringToPoint(offsetStr, ",")
		if err != nil {
			return fmt.Errorf("Illegal offset specification: %s: %v", offsetStr, err)
		}

		// Get list of files to add
		var addedFiles string
		if len(filenames) == 1 {
			addedFiles = filenames[0]
		} else {
			addedFiles = fmt.Sprintf("filenames: %s [%d more]", filenames[0], len(filenames)-1)
		}
		dvid.Debugf(addedFiles + "\n")

		uuid, versionID, err := datastore.MatchingUUID(uuidStr)
		if err != nil {
			return err
		}
		if err = datastore.AddToNodeLog(uuid, []string{req.Command.String()}); err != nil {
			return err
		}
		if err = d.LoadImages(versionID, offset, filenames); err != nil {
			return err
		}
		if err := datastore.SaveDataByUUID(uuid, d); err != nil {
			return err
		}
		return nil

	case "composite":
		if len(req.Command) < 6 {
			return fmt.Errorf("Poorly formatted composite command.  See command-line help.")
		}
		return d.CreateComposite(req, reply)

	default:
		return fmt.Errorf("Unknown command.  Data type '%s' [%s] does not support '%s' command.",
			d.DataName(), d.TypeName(), req.TypeCommand())
	}
	return nil
}

// SetMetadata loads JSON data giving MinTileCoord, MaxTileCoord, and tile level specifications.
func (d *Data) SetMetadata(uuid dvid.UUID, jsonBytes []byte) error {
	var config metadataJSON
	if err := json.Unmarshal(jsonBytes, &config); err != nil {
		return err
	}
	tileSpec, err := parseTileSpec(config.Levels)
	if err != nil {
		return err
	}

	d.Levels = tileSpec
	d.MinTileCoord = config.MinTileCoord
	d.MaxTileCoord = config.MaxTileCoord
	if err := datastore.SaveDataByUUID(uuid, d); err != nil {
		return err
	}
	return nil
}

func TestMultiscale2dRepoPersistence(t *testing.T) {
	datastore.OpenTest()
	defer datastore.CloseTest()

	// Make source
	uuid, _ := initTestRepo()
	makeGrayscale(uuid, t, "grayscale")

	// Make labels and set various properties
	config := dvid.NewConfig()
	config.Set("Placeholder", "true")
	config.Set("Format", "jpg")
	config.Set("Source", "grayscale")
	dataservice, err := datastore.NewData(uuid, mstype, "myimagetile", config)
	if err != nil {
		t.Errorf("Unable to create imagetile instance: %v\n", err)
	}
	msdata, ok := dataservice.(*Data)
	if !ok {
		t.Fatalf("Can't cast imagetile data service into imagetile.Data\n")
	}
	oldData := *msdata

	// Restart test datastore and see if datasets are still there.
	if err = datastore.SaveDataByUUID(uuid, msdata); err != nil {
		t.Fatalf("Unable to save repo during imagetile persistence test: %v\n", err)
	}
	datastore.CloseReopenTest()

	dataservice2, err := datastore.GetDataByUUID(uuid, "myimagetile")
	if err != nil {
		t.Fatalf("Can't get keyvalue instance from reloaded test db: %v\n", err)
	}
	msdata2, ok := dataservice2.(*Data)
	if !ok {
		t.Errorf("Returned new data instance 2 is not imagetile.Data\n")
	}

	if !reflect.DeepEqual(oldData.Properties, msdata2.Properties) {
		t.Errorf("Expected properties %v, got %v\n", oldData.Properties, msdata2.Properties)
	}
}

func TestFloat32RepoPersistence(t *testing.T) {
	datastore.OpenTest()
	defer datastore.CloseTest()

	uuid, _ := initTestRepo()

	// Make grayscale and set various properties
	config := dvid.NewConfig()
	config.Set("BlockSize", "12,13,14")
	config.Set("VoxelSize", "1.1,2.8,11")
	config.Set("VoxelUnits", "microns,millimeters,nanometers")
	dataservice, err := datastore.NewData(uuid, floatimgT, "floatimg", config)
	if err != nil {
		t.Errorf("Unable to create float32 instance: %s\n", err)
	}
	floatimg, ok := dataservice.(*Data)
	if !ok {
		t.Errorf("Can't cast float32 data service into Data\n")
	}
	oldData := *floatimg

	// Restart test datastore and see if datasets are still there.
	if err = datastore.SaveDataByUUID(uuid, floatimg); err != nil {
		t.Fatalf("Unable to save repo during floatimg persistence test: %v\n", err)
	}
	datastore.CloseReopenTest()

	dataservice2, err := datastore.GetDataByUUIDName(uuid, "floatimg")
	if err != nil {
		t.Fatalf("Can't get floatimg instance from reloaded test db: %v\n", err)
	}
	floatimg2, ok := dataservice2.(*Data)
	if !ok {
		t.Errorf("Returned new data instance 2 is not imageblk.Data\n")
	}
	if !oldData.Equals(floatimg2) {
		t.Errorf("Expected %v, got %v\n", oldData, *floatimg2)
	}
}

func TestLabelblkRepoPersistence(t *testing.T) {
	tests.UseStore()
	defer tests.CloseStore()

	uuid, _ := initTestRepo()

	// Make labels and set various properties
	config := dvid.NewConfig()
	config.Set("BlockSize", "12,13,14")
	config.Set("VoxelSize", "1.1,2.8,11")
	config.Set("VoxelUnits", "microns,millimeters,nanometers")
	dataservice, err := datastore.NewData(uuid, labelsT, "mylabels", config)
	if err != nil {
		t.Errorf("Unable to create labels instance: %v\n", err)
	}
	labels, ok := dataservice.(*Data)
	if !ok {
		t.Errorf("Can't cast labels data service into Data\n")
	}
	oldData := *labels

	// Restart test datastore and see if datasets are still there.
	if err = datastore.SaveDataByUUID(uuid, labels); err != nil {
		t.Fatalf("Unable to save repo during labels persistence test: %v\n", err)
	}
	tests.CloseReopenStore()

	dataservice2, err := datastore.GetDataByUUID(uuid, "mylabels")
	if err != nil {
		t.Fatalf("Can't get labels instance from reloaded test db: %v\n", err)
	}
	labels2, ok := dataservice2.(*Data)
	if !ok {
		t.Errorf("Returned new data instance 2 is not imageblk.Data\n")
	}
	if !oldData.Equals(labels2) {
		t.Errorf("Expected %v, got %v\n", oldData, *labels2)
	}
}

func TestKeyvalueRepoPersistence(t *testing.T) {
	tests.UseStore()
	defer tests.CloseStore()

	uuid, _ := initTestRepo()

	// Make labels and set various properties
	config := dvid.NewConfig()
	dataservice, err := datastore.NewData(uuid, kvtype, "mykv", config)
	if err != nil {
		t.Errorf("Unable to create keyvalue instance: %v\n", err)
	}
	kvdata, ok := dataservice.(*Data)
	if !ok {
		t.Errorf("Can't cast keyvalue data service into keyvalue.Data\n")
	}
	oldData := *kvdata

	// Restart test datastore and see if datasets are still there.
	if err = datastore.SaveDataByUUID(uuid, kvdata); err != nil {
		t.Fatalf("Unable to save repo during keyvalue persistence test: %v\n", err)
	}
	tests.CloseReopenStore()

	dataservice2, err := datastore.GetDataByUUID(uuid, "mykv")
	if err != nil {
		t.Fatalf("Can't get keyvalue instance from reloaded test db: %v\n", err)
	}
	kvdata2, ok := dataservice2.(*Data)
	if !ok {
		t.Errorf("Returned new data instance 2 is not keyvalue.Data\n")
	}
	if !oldData.Equals(kvdata2) {
		t.Errorf("Expected %v, got %v\n", oldData, *kvdata2)
	}
}

func TestMultichan16RepoPersistence(t *testing.T) {
	datastore.OpenTest()
	defer datastore.CloseTest()

	uuid, _ := initTestRepo()

	// Make labels and set various properties
	config := dvid.NewConfig()
	dataservice, err := datastore.NewData(uuid, dtype, "mymultichan16", config)
	if err != nil {
		t.Errorf("Unable to create multichan16 instance: %v\n", err)
	}
	mcdata, ok := dataservice.(*Data)
	if !ok {
		t.Errorf("Can't cast multichan16 data service into multichan16.Data\n")
	}
	oldData := *mcdata

	// Restart test datastore and see if datasets are still there.
	if err = datastore.SaveDataByUUID(uuid, mcdata); err != nil {
		t.Fatalf("Unable to save repo during multichan16 persistence test: %v\n", err)
	}
	datastore.CloseReopenTest()

	dataservice2, err := datastore.GetDataByUUIDName(uuid, "mymultichan16")
	if err != nil {
		t.Fatalf("Can't get multichan16 instance from reloaded test db: %v\n", err)
	}
	mcdata2, ok := dataservice2.(*Data)
	if !ok {
		t.Errorf("Returned new data instance 2 is not multichan16.Data\n")
	}
	if !oldData.Equals(mcdata2) {
		t.Errorf("Expected %v, got %v\n", oldData, *mcdata2)
	}
}

// ServeHTTP handles all incoming HTTP requests for this data.
func (d *Data) ServeHTTP(uuid dvid.UUID, ctx *datastore.VersionedCtx, w http.ResponseWriter, r *http.Request) {
	timedLog := dvid.NewTimeLog()
	// versionID := ctx.VersionID()

	// Get the action (GET, POST)
	action := strings.ToLower(r.Method)

	// Break URL request into arguments
	url := r.URL.Path[len(server.WebAPIPath):]
	parts := strings.Split(url, "/")
	if len(parts[len(parts)-1]) == 0 {
		parts = parts[:len(parts)-1]
	}

	// Handle POST on data -> setting of configuration
	if len(parts) == 3 && action == "put" {
		config, err := server.DecodeJSON(r)
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		if err := d.ModifyConfig(config); err != nil {
			server.BadRequest(w, r, err)
			return
		}
		if err := datastore.SaveDataByUUID(uuid, d); err != nil {
			server.BadRequest(w, r, err)
			return
		}
		fmt.Fprintf(w, "Changed '%s' based on received configuration:\n%s\n", d.DataName(), config)
		return
	}

	if len(parts) < 4 {
		server.BadRequest(w, r, "Incomplete API request")
		return
	}

	// Process help and info.
	switch parts[3] {
	case "help":
		w.Header().Set("Content-Type", "text/plain")
		fmt.Fprintln(w, dtype.Help())

	case "info":
		jsonBytes, err := d.MarshalJSON()
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		w.Header().Set("Content-Type", "application/json")
		fmt.Fprintf(w, string(jsonBytes))

	case "sync":
		if action != "post" {
			server.BadRequest(w, r, "Only POST allowed to sync endpoint")
			return
		}
		replace := r.URL.Query().Get("replace") == "true"
		if err := datastore.SetSyncByJSON(d, uuid, replace, r.Body); err != nil {
			server.BadRequest(w, r, err)
			return
		}

	case "label":
		if action != "get" {
			server.BadRequest(w, r, "Only GET action is available on 'label' endpoint.")
			return
		}
		if len(parts) < 5 {
			server.BadRequest(w, r, "Must include label after 'label' endpoint.")
			return
		}
		label, err := strconv.ParseUint(parts[4], 10, 64)
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		if label == 0 {
			server.BadRequest(w, r, "Label 0 is protected background value and cannot be used for query.")
			return
		}
		queryStrings := r.URL.Query()
		jsonBytes, err := d.GetLabelJSON(ctx, label, queryStrings.Get("relationships") == "true")
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		w.Header().Set("Content-type", "application/json")
		if _, err := w.Write(jsonBytes); err != nil {
			server.BadRequest(w, r, err)
			return
		}
		timedLog.Infof("HTTP %s: get synaptic elements for label %d (%s)", r.Method, label, r.URL)

	case "tag":
		if action != "get" {
			server.BadRequest(w, r, "Only GET action is available on 'tag' endpoint.")
			return
//.........这里部分代码省略.........

// LoadLocal adds image data to a version node.  See HelpMessage for example of
// command-line use of "load local".
func (d *Data) LoadLocal(request datastore.Request, reply *datastore.Response) error {
	timedLog := dvid.NewTimeLog()

	// Parse the request
	var uuidStr, dataName, cmdStr, sourceStr, filename string
	_ = request.CommandArgs(1, &uuidStr, &dataName, &cmdStr, &sourceStr, &filename)

	// Get the uuid from a uniquely identifiable string
	uuid, versionID, err := datastore.MatchingUUID(uuidStr)
	if err != nil {
		return fmt.Errorf("Could not find node with UUID %s: %v", uuidStr, err)
	}

	// Load the V3D Raw file.
	ext := filepath.Ext(filename)
	switch ext {
	case ".raw", ".v3draw":
	default:
		return fmt.Errorf("Unknown extension '%s' when expected V3D Raw file", ext)
	}
	file, err := os.Open(filename)
	if err != nil {
		return err
	}
	unmarshaler := V3DRawMarshaler{}
	channels, err := unmarshaler.UnmarshalV3DRaw(file)
	if err != nil {
		return err
	}

	// Store the metadata
	d.NumChannels = len(channels)
	d.Properties.Values = make(dvid.DataValues, d.NumChannels)
	if d.NumChannels > 0 {
		reply.Text = fmt.Sprintf("Loaded %s into data '%s': found %d channels\n",
			d.DataName(), filename, d.NumChannels)
		reply.Text += fmt.Sprintf(" %s", channels[0])
	} else {
		reply.Text = fmt.Sprintf("Found no channels in file %s\n", filename)
		return nil
	}
	for i, channel := range channels {
		d.Properties.Values[i] = channel.Voxels.Values()[0]
	}

	// Get repo and save it.
	if err := datastore.SaveDataByUUID(uuid, d); err != nil {
		return err
	}

	// PUT each channel of the file into the datastore using a separate data name.
	for _, channel := range channels {
		dvid.Infof("Processing channel %d... \n", channel.channelNum)
		err = d.PutVoxels(versionID, channel.Voxels, nil)
		if err != nil {
			return err
		}
	}

	// Create a RGB composite from the first 3 channels.  This is considered to be channel 0
	// or can be accessed with the base data name.
	dvid.Infof("Creating composite image from channels...\n")
	err = d.storeComposite(versionID, channels)
	if err != nil {
		return err
	}

	timedLog.Infof("RPC load local '%s' completed", filename)
	return nil
}

func (d *Data) ConstructTiles(uuidStr string, tileSpec TileSpec, request datastore.Request) error {
	config := request.Settings()
	uuid, versionID, err := datastore.MatchingUUID(uuidStr)
	if err != nil {
		return err
	}
	if err = datastore.AddToNodeLog(uuid, []string{request.Command.String()}); err != nil {
		return err
	}

	source, err := datastore.GetDataByUUID(uuid, d.Source)
	if err != nil {
		return err
	}
	src, ok := source.(*imageblk.Data)
	if !ok {
		return fmt.Errorf("Cannot construct imagetile for non-voxels data: %s", d.Source)
	}

	// Save the current tile specification
	d.Levels = tileSpec
	if err := datastore.SaveDataByUUID(uuid, d); err != nil {
		return err
	}

	// Get size of tile at lowest resolution.
	lastLevel := Scaling(len(tileSpec) - 1)
	loresSpec, found := tileSpec[lastLevel]
	if !found {
		return fmt.Errorf("Illegal tile spec.  Should have levels 0 to absent %d.", lastLevel)
	}
	var loresSize [3]float64
	for i := 0; i < 3; i++ {
		loresSize[i] = float64(loresSpec.Resolution[i]) * float64(DefaultTileSize[i])
	}
	loresMag := dvid.Point3d{1, 1, 1}
	for i := Scaling(0); i < lastLevel; i++ {
		levelMag := tileSpec[i].levelMag
		loresMag[0] *= levelMag[0]
		loresMag[1] *= levelMag[1]
		loresMag[2] *= levelMag[2]
	}

	// Get min and max points in terms of distance.
	var minPtDist, maxPtDist [3]float64
	for i := uint8(0); i < 3; i++ {
		minPtDist[i] = float64(src.MinPoint.Value(i)) * float64(src.VoxelSize[i])
		maxPtDist[i] = float64(src.MaxPoint.Value(i)) * float64(src.VoxelSize[i])
	}

	// Adjust min and max points for the tileable surface at lowest resolution.
	var minTiledPt, maxTiledPt dvid.Point3d
	for i := 0; i < 3; i++ {
		minInt, _ := math.Modf(minPtDist[i] / loresSize[i])
		maxInt, _ := math.Modf(maxPtDist[i] / loresSize[i])
		minTileCoord := int32(minInt)
		maxTileCoord := int32(maxInt)
		minTiledPt[i] = minTileCoord * DefaultTileSize[i] * loresMag[i]
		maxTiledPt[i] = (maxTileCoord+1)*DefaultTileSize[i]*loresMag[i] - 1
	}
	sizeVolume := maxTiledPt.Sub(minTiledPt).AddScalar(1)

	// Setup swappable ExtData buffers (the stitched slices) so we can be generating tiles
	// at same time we are reading and stitching them.
	var bufferLock [2]sync.Mutex
	var sliceBuffers [2]*imageblk.Voxels
	var bufferNum int

	// Get the planes we should tile.
	planes, err := config.GetShapes("planes", ";")
	if planes == nil {
		// If no planes are specified, construct imagetile for 3 orthogonal planes.
		planes = []dvid.DataShape{dvid.XY, dvid.XZ, dvid.YZ}
	}

	outF, err := d.putTileFunc(versionID)

	// sort the tile spec keys to iterate from highest to lowest resolution
	var sortedKeys []int
	for scaling, _ := range tileSpec {
		sortedKeys = append(sortedKeys, int(scaling))
	}
	sort.Ints(sortedKeys)

	for _, plane := range planes {
		timedLog := dvid.NewTimeLog()
		offset := minTiledPt.Duplicate()

		switch {

		case plane.Equals(dvid.XY):
			width, height, err := plane.GetSize2D(sizeVolume)
			if err != nil {
				return err
			}
			dvid.Debugf("Tiling XY image %d x %d pixels\n", width, height)
			for z := src.MinPoint.Value(2); z <= src.MaxPoint.Value(2); z++ {
				server.BlockOnInteractiveRequests("imagetile.ConstructTiles [xy]")

				sliceLog := dvid.NewTimeLog()
//.........这里部分代码省略.........

// CreateComposite creates a new rgba8 image by combining hash of labels + the grayscale
func (d *Data) CreateComposite(request datastore.Request, reply *datastore.Response) error {
	timedLog := dvid.NewTimeLog()

	// Parse the request
	var uuidStr, dataName, cmdStr, grayscaleName, destName string
	request.CommandArgs(1, &uuidStr, &dataName, &cmdStr, &grayscaleName, &destName)

	// Get the version
	uuid, v, err := datastore.MatchingUUID(uuidStr)
	if err != nil {
		return err
	}

	// Log request
	if err = datastore.AddToNodeLog(uuid, []string{request.Command.String()}); err != nil {
		return err
	}

	// Get the grayscale data.
	dataservice, err := datastore.GetDataByUUIDName(uuid, dvid.InstanceName(grayscaleName))
	if err != nil {
		return err
	}
	grayscale, ok := dataservice.(*imageblk.Data)
	if !ok {
		return fmt.Errorf("%s is not the name of uint8 data", grayscaleName)
	}

	// Create a new rgba8blk data.
	var compservice datastore.DataService
	compservice, err = datastore.GetDataByUUIDName(uuid, dvid.InstanceName(destName))
	if err == nil {
		return fmt.Errorf("Data instance with name %q already exists", destName)
	}
	typeService, err := datastore.TypeServiceByName("rgba8blk")
	if err != nil {
		return fmt.Errorf("Could not get rgba8 type service from DVID")
	}
	config := dvid.NewConfig()
	compservice, err = datastore.NewData(uuid, typeService, dvid.InstanceName(destName), config)
	if err != nil {
		return err
	}
	composite, ok := compservice.(*imageblk.Data)
	if !ok {
		return fmt.Errorf("Error: %s was unable to be set to rgba8 data", destName)
	}

	// Iterate through all labels and grayscale chunks incrementally in Z, a layer at a time.
	wg := new(sync.WaitGroup)
	op := &compositeOp{grayscale, composite, v}
	chunkOp := &storage.ChunkOp{op, wg}

	store, err := d.GetOrderedKeyValueDB()
	if err != nil {
		return err
	}
	ctx := datastore.NewVersionedCtx(d, v)
	extents := d.Extents()
	blockBeg := imageblk.NewTKey(extents.MinIndex)
	blockEnd := imageblk.NewTKey(extents.MaxIndex)
	err = store.ProcessRange(ctx, blockBeg, blockEnd, chunkOp, storage.ChunkFunc(d.CreateCompositeChunk))
	wg.Wait()

	// Set new mapped data to same extents.
	composite.Properties.Extents = grayscale.Properties.Extents
	if err := datastore.SaveDataByUUID(uuid, composite); err != nil {
		dvid.Infof("Could not save new data '%s': %v\n", destName, err)
	}

	timedLog.Infof("Created composite of %s and %s", grayscaleName, destName)
	return nil
}

// ServeHTTP handles all incoming HTTP requests for this data.
func (d *Data) ServeHTTP(uuid dvid.UUID, ctx *datastore.VersionedCtx, w http.ResponseWriter, r *http.Request) {
	// TODO -- Refactor this method to break it up and make it simpler.  Use the web routing for the endpoints.

	timedLog := dvid.NewTimeLog()

	// Get the action (GET, POST)
	action := strings.ToLower(r.Method)
	switch action {
	case "get":
	case "post":
	case "delete":
	default:
		server.BadRequest(w, r, "labelblk only handles GET, POST, and DELETE HTTP verbs")
		return
	}

	// Break URL request into arguments
	url := r.URL.Path[len(server.WebAPIPath):]
	parts := strings.Split(url, "/")
	if len(parts[len(parts)-1]) == 0 {
		parts = parts[:len(parts)-1]
	}

	// Get query strings and possible roi
	var roiptr *imageblk.ROI
	queryValues := r.URL.Query()
	roiname := dvid.InstanceName(queryValues.Get("roi"))
	if len(roiname) != 0 {
		roiptr = new(imageblk.ROI)
	}

	// Handle POST on data -> setting of configuration
	if len(parts) == 3 && action == "post" {
		config, err := server.DecodeJSON(r)
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		if err := d.ModifyConfig(config); err != nil {
			server.BadRequest(w, r, err)
			return
		}
		if err := datastore.SaveDataByUUID(uuid, d); err != nil {
			server.BadRequest(w, r, err)
			return
		}
		fmt.Fprintf(w, "Changed '%s' based on received configuration:\n%s\n", d.DataName(), config)
		return
	}

	if len(parts) < 4 {
		server.BadRequest(w, r, "Incomplete API request")
		return
	}

	// Process help and info.
	switch parts[3] {
	case "help":
		w.Header().Set("Content-Type", "text/plain")
		fmt.Fprintln(w, dtype.Help())

	case "metadata":
		jsonStr, err := d.NdDataMetadata()
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		w.Header().Set("Content-Type", "application/vnd.dvid-nd-data+json")
		fmt.Fprintln(w, jsonStr)

	case "info":
		jsonBytes, err := d.MarshalJSON()
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		w.Header().Set("Content-Type", "application/json")
		fmt.Fprintf(w, string(jsonBytes))

	case "label":
		// GET <api URL>/node/<UUID>/<data name>/label/<coord>
		if len(parts) < 5 {
			server.BadRequest(w, r, "DVID requires coord to follow 'label' command")
			return
		}
		coord, err := dvid.StringToPoint(parts[4], "_")
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		label, err := d.GetLabelAtPoint(ctx.VersionID(), coord)
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		w.Header().Set("Content-type", "application/json")
		jsonStr := fmt.Sprintf(`{"Label": %d}`, label)
		fmt.Fprintf(w, jsonStr)
		timedLog.Infof("HTTP %s: label at %s (%s)", r.Method, coord, r.URL)
//.........这里部分代码省略.........

// ServeHTTP handles all incoming HTTP requests for this data.
func (d *Data) ServeHTTP(uuid dvid.UUID, ctx *datastore.VersionedCtx, w http.ResponseWriter, r *http.Request) {
	timedLog := dvid.NewTimeLog()

	// Get the action (GET, POST)
	action := strings.ToLower(r.Method)

	// Break URL request into arguments
	url := r.URL.Path[len(server.WebAPIPath):]
	parts := strings.Split(url, "/")
	if len(parts[len(parts)-1]) == 0 {
		parts = parts[:len(parts)-1]
	}

	// Handle POST on data -> setting of configuration
	if len(parts) == 3 && action == "put" {
		config, err := server.DecodeJSON(r)
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		if err := d.ModifyConfig(config); err != nil {
			server.BadRequest(w, r, err)
			return
		}
		if err := datastore.SaveDataByUUID(uuid, d); err != nil {
			server.BadRequest(w, r, err)
			return
		}
		fmt.Fprintf(w, "Changed '%s' based on received configuration:\n%s\n", d.DataName(), config)
		return
	}

	if len(parts) < 4 {
		server.BadRequest(w, r, "Incomplete API request")
		return
	}

	// Process help and info.
	switch parts[3] {
	case "help":
		w.Header().Set("Content-Type", "text/plain")
		fmt.Fprintln(w, dtype.Help())

	case "info":
		jsonBytes, err := d.MarshalJSON()
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		w.Header().Set("Content-Type", "application/json")
		fmt.Fprintf(w, string(jsonBytes))

	case "sync":
		if action != "post" {
			server.BadRequest(w, r, "Only POST allowed to sync endpoint")
			return
		}
		replace := r.URL.Query().Get("replace") == "true"
		if err := datastore.SetSyncByJSON(d, uuid, replace, r.Body); err != nil {
			server.BadRequest(w, r, err)
			return
		}

	case "count":
		if action != "get" {
			server.BadRequest(w, r, "Only GET action is available on 'count' endpoint.")
			return
		}
		if len(parts) < 6 {
			server.BadRequest(w, r, "Must include label and element type after 'count' endpoint.")
			return
		}
		label, err := strconv.ParseUint(parts[4], 10, 64)
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		i := StringToIndexType(parts[5])
		if i == UnknownIndex {
			server.BadRequest(w, r, fmt.Errorf("unknown index type specified (%q)", parts[5]))
			return
		}
		count, err := d.GetCountElementType(ctx, label, i)
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		w.Header().Set("Content-type", "application/json")
		jsonStr := fmt.Sprintf(`{"Label":%d,%q:%d}`, label, i, count)
		if _, err := io.WriteString(w, jsonStr); err != nil {
			server.BadRequest(w, r, err)
			return
		}
		timedLog.Infof("HTTP %s: get count for label %d, index type %s: %s", r.Method, label, i, r.URL)

	case "top":
		if action != "get" {
			server.BadRequest(w, r, "Only GET action is available on 'top' endpoint.")
			return
//.........这里部分代码省略.........

// ServeHTTP handles all incoming HTTP requests for this data.
func (d *Data) ServeHTTP(uuid dvid.UUID, ctx *datastore.VersionedCtx, w http.ResponseWriter, r *http.Request) {
	timedLog := dvid.NewTimeLog()

	action := strings.ToLower(r.Method)
	switch action {
	case "get", "post":
		// Acceptable
	default:
		server.BadRequest(w, r, "Can only handle GET or POST HTTP verbs")
		return
	}

	// Break URL request into arguments
	url := r.URL.Path[len(server.WebAPIPath):]
	parts := strings.Split(url, "/")
	if len(parts[len(parts)-1]) == 0 {
		parts = parts[:len(parts)-1]
	}
	if len(parts) < 4 {
		server.BadRequest(w, r, "incomplete API request")
		return
	}

	switch parts[3] {
	case "help":
		w.Header().Set("Content-Type", "text/plain")
		fmt.Fprintln(w, d.Help())

	case "info":
		jsonBytes, err := d.MarshalJSON()
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		w.Header().Set("Content-Type", "application/json")
		fmt.Fprintf(w, string(jsonBytes))

	case "metadata":
		switch action {
		case "post":
			jsonBytes, err := ioutil.ReadAll(r.Body)
			if err != nil {
				server.BadRequest(w, r, err)
				return
			}
			tilespec, err := LoadTileSpec(jsonBytes)
			if err != nil {
				server.BadRequest(w, r, err)
				return
			}
			d.Levels = tilespec
			if err := datastore.SaveDataByUUID(uuid, d); err != nil {
				server.BadRequest(w, r, err)
				return
			}

		case "get":
			if d.Levels == nil || len(d.Levels) == 0 {
				server.BadRequest(w, r, "tile metadata for imagetile %q was not set\n", d.DataName())
				return
			}
			jsonBytes, err := d.Levels.MarshalJSON()
			if err != nil {
				server.BadRequest(w, r, err)
				return
			}
			w.Header().Set("Content-Type", "application/json")
			fmt.Fprintf(w, string(jsonBytes))
		}
		timedLog.Infof("HTTP %s: metadata (%s)", r.Method, r.URL)

	case "tile":
		switch action {
		case "post":
			err := d.PostTile(uuid, ctx, w, r, parts)
			if err != nil {
				server.BadRequest(w, r, "Error in posting tile with URL %q: %v\n", url, err)
				return
			}
		case "get":
			if err := d.ServeTile(uuid, ctx, w, r, parts); err != nil {
				server.BadRequest(w, r, err)
				return
			}
		}
		timedLog.Infof("HTTP %s: tile (%s)", r.Method, r.URL)

	case "tilekey":
		switch action {
		case "get":
			var err error
			var hexkey string
			if hexkey, err = d.GetTileKey(uuid, ctx, w, r, parts); err != nil {
				server.BadRequest(w, r, err)
				return
			}
			w.Header().Set("Content-Type", "application/json")
			fmt.Fprintf(w, `{"key": "%s"}`, hexkey)
			timedLog.Infof("HTTP %s: tilekey (%s) returns %s", r.Method, r.URL, hexkey)
//.........这里部分代码省略.........

// ServeHTTP handles all incoming HTTP requests for this data.
func (d *Data) ServeHTTP(uuid dvid.UUID, ctx *datastore.VersionedCtx, w http.ResponseWriter, r *http.Request) {
	timedLog := dvid.NewTimeLog()

	// Get the action (GET, POST)
	action := strings.ToLower(r.Method)
	switch action {
	case "get":
	case "post":
	default:
		server.BadRequest(w, r, "Can only handle GET or POST HTTP verbs")
		return
	}

	// Break URL request into arguments
	url := r.URL.Path[len(server.WebAPIPath):]
	parts := strings.Split(url, "/")
	if len(parts[len(parts)-1]) == 0 {
		parts = parts[:len(parts)-1]
	}

	// Get query strings and possible roi
	var roiptr *ROI
	queryValues := r.URL.Query()
	roiname := dvid.InstanceName(queryValues.Get("roi"))
	if len(roiname) != 0 {
		roiptr = new(ROI)
		attenuationStr := queryValues.Get("attenuation")
		if len(attenuationStr) != 0 {
			attenuation, err := strconv.Atoi(attenuationStr)
			if err != nil {
				server.BadRequest(w, r, err)
				return
			}
			if attenuation < 1 || attenuation > 7 {
				server.BadRequest(w, r, "Attenuation should be from 1 to 7 (divides by 2^n)")
				return
			}
			roiptr.attenuation = uint8(attenuation)
		}
	}

	// Handle POST on data -> setting of configuration
	if len(parts) == 3 && action == "put" {
		fmt.Printf("Setting configuration of data '%s'\n", d.DataName())
		config, err := server.DecodeJSON(r)
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		if err := d.ModifyConfig(config); err != nil {
			server.BadRequest(w, r, err)
			return
		}
		if err := datastore.SaveDataByUUID(uuid, d); err != nil {
			server.BadRequest(w, r, err)
			return
		}
		fmt.Fprintf(w, "Changed '%s' based on received configuration:\n%s\n", d.DataName(), config)
		return
	}

	if len(parts) < 4 {
		server.BadRequest(w, r, "Incomplete API request")
		return
	}

	// Process help and info.
	switch parts[3] {
	case "help":
		w.Header().Set("Content-Type", "text/plain")
		fmt.Fprintln(w, d.Help())
		return

	case "metadata":
		jsonStr, err := d.NdDataMetadata()
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		w.Header().Set("Content-Type", "application/vnd.dvid-nd-data+json")
		fmt.Fprintln(w, jsonStr)
		return

	case "info":
		jsonBytes, err := d.MarshalJSON()
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		w.Header().Set("Content-Type", "application/json")
		fmt.Fprintf(w, string(jsonBytes))
		return

	case "rawkey":
		// GET <api URL>/node/<UUID>/<data name>/rawkey?x=<block x>&y=<block y>&z=<block z>
		if len(parts) != 4 {
			server.BadRequest(w, r, "rawkey endpoint should be followed by query strings (x, y, and z) giving block coord")
			return
		}
//.........这里部分代码省略.........

func TestROIRepoPersistence(t *testing.T) {
	datastore.OpenTest()
	defer datastore.CloseTest()

	uuid, _ := initTestRepo()

	// Add data
	config := dvid.NewConfig()
	dataservice1, err := datastore.NewData(uuid, roitype, "myroi", config)
	if err != nil {
		t.Errorf("Error creating new roi instance: %v\n", err)
	}
	roi1, ok := dataservice1.(*Data)
	if !ok {
		t.Errorf("Returned new data instance 1 is not roi.Data\n")
	}
	if roi1.DataName() != "myroi" {
		t.Errorf("New roi data instance name set incorrectly: %q != %q\n",
			roi1.DataName(), "myroi")
	}

	config.Set("BlockSize", "15,16,17")
	dataservice2, err := datastore.NewData(uuid, roitype, "myroi2", config)
	if err != nil {
		t.Errorf("Error creating new roi instance: %v\n", err)
	}
	roi2, ok := dataservice2.(*Data)
	if !ok {
		t.Errorf("Returned new data instance 2 is not roi.Data\n")
	}
	roi2.MinZ = 13
	roi2.MaxZ = 3098
	oldData := *roi2

	// Check instance IDs
	if roi1.InstanceID() == roi2.InstanceID() {
		t.Errorf("Instance IDs should be different: %d == %d\n",
			roi1.InstanceID(), roi2.InstanceID())
	}

	// Restart test datastore and see if datasets are still there.
	if err = datastore.SaveDataByUUID(uuid, dataservice1); err != nil {
		t.Fatalf("Unable to save data1 during ROI persistence test: %v\n", err)
	}
	if err = datastore.SaveDataByUUID(uuid, dataservice2); err != nil {
		t.Fatalf("Unable to save data2 during ROI persistence test: %v\n", err)
	}

	datastore.CloseReopenTest()

	dataservice3, err := datastore.GetDataByUUID(uuid, "myroi2")
	if err != nil {
		t.Fatalf("Can't get first ROI instance from reloaded test db: %v\n", err)
	}
	roi2new, ok := dataservice3.(*Data)
	if !ok {
		t.Errorf("Returned new data instance 3 is not roi.Data\n")
	}
	if !oldData.Equals(roi2new) {
		t.Errorf("Expected %v, got %v\n", oldData, *roi2new)
	}
}

// ServeHTTP handles all incoming HTTP requests for this data.
func (d *Data) ServeHTTP(uuid dvid.UUID, ctx *datastore.VersionedCtx, w http.ResponseWriter, r *http.Request) {
	timedLog := dvid.NewTimeLog()
	versionID := ctx.VersionID()

	// Get the action (GET, POST)
	action := strings.ToLower(r.Method)

	// Break URL request into arguments
	url := r.URL.Path[len(server.WebAPIPath):]
	parts := strings.Split(url, "/")
	if len(parts[len(parts)-1]) == 0 {
		parts = parts[:len(parts)-1]
	}

	// Handle POST on data -> setting of configuration
	if len(parts) == 3 && action == "put" {
		config, err := server.DecodeJSON(r)
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		if err := d.ModifyConfig(config); err != nil {
			server.BadRequest(w, r, err)
			return
		}
		if err := datastore.SaveDataByUUID(uuid, d); err != nil {
			server.BadRequest(w, r, err)
			return
		}
		fmt.Fprintf(w, "Changed '%s' based on received configuration:\n%s\n", d.DataName(), config)
		return
	}

	if len(parts) < 4 {
		server.BadRequest(w, r, "Incomplete API request")
		return
	}

	// Process help and info.
	switch parts[3] {
	case "help":
		w.Header().Set("Content-Type", "text/plain")
		fmt.Fprintln(w, dtype.Help())

	case "info":
		jsonBytes, err := d.MarshalJSON()
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		w.Header().Set("Content-Type", "application/json")
		fmt.Fprintf(w, string(jsonBytes))

	case "sparsevol":
		// GET <api URL>/node/<UUID>/<data name>/sparsevol/<label>
		// POST <api URL>/node/<UUID>/<data name>/sparsevol/<label>
		if len(parts) < 5 {
			server.BadRequest(w, r, "ERROR: DVID requires label ID to follow 'sparsevol' command")
			return
		}
		label, err := strconv.ParseUint(parts[4], 10, 64)
		if err != nil {
			server.BadRequest(w, r, err)
			return
		}
		switch action {
		case "get":
			queryValues := r.URL.Query()
			var b Bounds
			b.VoxelBounds, err = dvid.BoundsFromQueryString(r)
			if err != nil {
				server.BadRequest(w, r, "Error parsing bounds from query string: %v\n", err)
				return
			}
			b.BlockBounds = b.VoxelBounds.Divide(d.BlockSize)
			b.Exact = queryValues.Get("exact") == "true"
			data, err := GetSparseVol(ctx, label, b)
			if err != nil {
				server.BadRequest(w, r, err)
				return
			}
			w.Header().Set("Content-type", "application/octet-stream")
			_, err = w.Write(data)
			if err != nil {
				server.BadRequest(w, r, err)
				return
			}
		case "post":
			server.BadRequest(w, r, "POST of sparsevol not currently implemented\n")
			return
			// if err := d.PutSparseVol(versionID, label, r.Body); err != nil {
			// 	server.BadRequest(w, r, err)
			// 	return
			// }
		default:
			server.BadRequest(w, r, "Unable to handle HTTP action %s on sparsevol endpoint", action)
			return
		}
		timedLog.Infof("HTTP %s: sparsevol on label %d (%s)", r.Method, label, r.URL)
//.........这里部分代码省略.........