feat: add file upload implement to v2 api (#1566)

Signed-off-by: CorrectRoadH <a778917369@gmail.com>

service/file_upload.go

@@ -0,0 +1,144 @@
+package service
+
+import (
+	"fmt"
+	"io"
+	"mime/multipart"
+	"os"
+	"sync"
+
+	"github.com/labstack/echo/v4"
+)
+
+type FileInfo struct {
+	init             bool
+	uploaded         []bool
+	uploadedChunkNum int64
+}
+
+type FileUploadService struct {
+	uploadStatus sync.Map
+	lock         sync.RWMutex
+}
+
+func NewFileUploadService() *FileUploadService {
+	return &FileUploadService{
+		uploadStatus: sync.Map{},
+		lock:         sync.RWMutex{},
+	}
+}
+
+func (s *FileUploadService) TestChunk(
+	c echo.Context,
+	identifier string,
+	chunkNumber int64,
+) error {
+	fileInfoTemp, ok := s.uploadStatus.Load(identifier)
+
+	if !ok {
+		return fmt.Errorf("file not found")
+	}
+
+	fileInfo := fileInfoTemp.(*FileInfo)
+
+	if !fileInfo.init {
+		return fmt.Errorf("file not init")
+	}
+
+	// return StatusNoContent instead of 404
+	// the is require by frontend
+	if !fileInfo.uploaded[chunkNumber-1] {
+		return fmt.Errorf("file not found")
+	}
+
+	return nil
+}
+
+func (s *FileUploadService) UploadFile(
+	c echo.Context,
+	path string,
+	chunkNumber int64,
+	chunkSize int64,
+	currentChunkSize int64,
+	totalChunks int64,
+	totalSize int64,
+	identifier string,
+	fileName string,
+	bin *multipart.FileHeader,
+) error {
+	s.lock.Lock()
+	fileInfoTemp, ok := s.uploadStatus.Load(identifier)
+	var fileInfo *FileInfo
+
+	file, err := os.OpenFile(path+"/"+fileName+".tmp", os.O_WRONLY|os.O_CREATE, 0644)
+	if err != nil {
+		s.lock.Unlock()
+		return err
+	}
+
+	if !ok {
+
+		if err != nil {
+			s.lock.Unlock()
+			return err
+		}
+
+		// pre allocate file size
+		fmt.Println("truncate", totalSize)
+		if err != nil {
+			s.lock.Unlock()
+			return err
+		}
+
+		// file info init
+		fileInfo = &FileInfo{
+			init:             true,
+			uploaded:         make([]bool, totalChunks),
+			uploadedChunkNum: 0,
+		}
+		s.uploadStatus.Store(identifier, fileInfo)
+	} else {
+		fileInfo = fileInfoTemp.(*FileInfo)
+	}
+
+	s.lock.Unlock()
+
+	_, err = file.Seek((chunkNumber-1)*chunkSize, io.SeekStart)
+	if err != nil {
+		return err
+	}
+
+	src, err := bin.Open()
+	if err != nil {
+		return err
+	}
+	defer src.Close()
+
+	buf := make([]byte, int(currentChunkSize))
+	_, err = io.CopyBuffer(file, src, buf)
+
+	if err != nil {
+		fmt.Println(err)
+		return err
+	}
+
+	s.lock.Lock()
+	// handle file after write a chunk
+	// handle single chunk upload twice
+	if !fileInfo.uploaded[chunkNumber-1] {
+		fileInfo.uploadedChunkNum++
+		fileInfo.uploaded[chunkNumber-1] = true
+	}
+
+	// handle file after write all chunk
+	if fileInfo.uploadedChunkNum == totalChunks {
+		file.Close()
+		os.Rename(path+"/"+fileName+".tmp", path+"/"+fileName)
+
+		// remove upload status info after upload complete
+		s.uploadStatus.Delete(identifier)
+	}
+	s.lock.Unlock()
+
+	return nil
+}