package file import ( "bufio" "context" "errors" "fmt" "io" "log" "os" "github.com/micro/go-micro/v2/client" proto "github.com/micro/go-micro/v2/util/file/proto" ) // Client is the client interface to access files type File interface { Open(filename string, truncate bool) (int64, error) Stat(filename string) (*proto.StatResponse, error) GetBlock(sessionId, blockId int64) ([]byte, error) ReadAt(sessionId, offset, size int64) ([]byte, error) Read(sessionId int64, buf []byte) (int, error) Write(sessionId, offset int64, data []byte) error Close(sessionId int64) error Download(filename, saveFile string) error Upload(filename, localFile string) error DownloadAt(filename, saveFile string, blockId int) error } // NewClient returns a new Client which uses a micro Client func New(service string, c client.Client) File { return &fc{proto.NewFileService(service, c)} } const ( blockSize = 512 * 1024 ) type fc struct { c proto.FileService } func (c *fc) Open(filename string, truncate bool) (int64, error) { rsp, err := c.c.Open(context.TODO(), &proto.OpenRequest{ Filename: filename, Truncate: truncate, }) if err != nil { return 0, err } return rsp.Id, nil } func (c *fc) Stat(filename string) (*proto.StatResponse, error) { return c.c.Stat(context.TODO(), &proto.StatRequest{Filename: filename}) } func (c *fc) GetBlock(sessionId, blockId int64) ([]byte, error) { return c.ReadAt(sessionId, blockId*blockSize, blockSize) } func (c *fc) ReadAt(sessionId, offset, size int64) ([]byte, error) { rsp, err := c.c.Read(context.TODO(), &proto.ReadRequest{Id: sessionId, Size: size, Offset: offset}) if err != nil { return nil, err } if rsp.Eof { err = io.EOF } if rsp.Data == nil { rsp.Data = make([]byte, size) } if size != rsp.Size { return rsp.Data[:rsp.Size], err } return rsp.Data, nil } func (c *fc) Read(sessionId int64, buf []byte) (int, error) { b, err := c.ReadAt(sessionId, 0, int64(cap(buf))) if err != nil { return 0, err } copy(buf, b) return len(b), nil } func (c *fc) Write(sessionId, offset int64, data []byte) error { _, err := c.c.Write(context.TODO(), &proto.WriteRequest{ Id: sessionId, Offset: offset, Data: data}) return err } func (c *fc) Close(sessionId int64) error { _, err := c.c.Close(context.TODO(), &proto.CloseRequest{Id: sessionId}) return err } func (c *fc) Download(filename, saveFile string) error { return c.DownloadAt(filename, saveFile, 0) } func (c *fc) Upload(filename, localFile string) error { file, err := os.Open(localFile) if err != nil { return err } defer file.Close() offset := 0 sessionId, err := c.Open(filename, true) defer c.Close(sessionId) if err != nil { return err } reader := bufio.NewReader(file) part := make([]byte, blockSize) for { count, err := reader.Read(part) if err != nil { break } err = c.Write(sessionId, int64(offset), part) if err != nil { return err } offset += count } if err != nil && err != io.EOF { return fmt.Errorf("Error reading %v: %v", localFile, err) } return nil } func (c *fc) DownloadAt(filename, saveFile string, blockId int) error { stat, err := c.Stat(filename) if err != nil { return err } if stat.Type == "Directory" { return errors.New(fmt.Sprintf("%s is directory.", filename)) } blocks := int(stat.Size / blockSize) if stat.Size%blockSize != 0 { blocks += 1 } log.Printf("Download %s in %d blocks\n", filename, blocks-blockId) file, err := os.OpenFile(saveFile, os.O_CREATE|os.O_WRONLY, 0666) if err != nil { return err } defer file.Close() sessionId, err := c.Open(filename, false) if err != nil { return err } for i := blockId; i < blocks; i++ { buf, rerr := c.GetBlock(sessionId, int64(i)) if rerr != nil && rerr != io.EOF { return rerr } if _, werr := file.WriteAt(buf, int64(i)*blockSize); werr != nil { return werr } if i%((blocks-blockId)/100+1) == 0 { log.Printf("Downloading %s [%d/%d] blocks", filename, i-blockId+1, blocks-blockId) } if rerr == io.EOF { break } } log.Printf("Download %s completed", filename) c.Close(sessionId) return nil }