Golang Part.Read方法代码示例

/**
  Check a value against a bounded(!) buffer
*/
func valCheck(buffer []byte, refVal []byte, checkedVal *multipart.Part) bool {
	totalBytesRead := 0
	bufferLength := len(buffer)
	for {
		if totalBytesRead >= bufferLength {
			break
		}
		bytesRead, err := checkedVal.Read(buffer[totalBytesRead:])
		if bytesRead < 0 || err == io.EOF {
			break
		}
		totalBytesRead += bytesRead
	}

	i := 0
	refValLength := len(refVal)
	if totalBytesRead != refValLength {
		return false
	}
	for i < refValLength {
		if refVal[i] != buffer[i] {
			return false
		}
		i++
	}

	return true

}

func WriteFileChunk(chunk *multipart.Part, file *os.File) error {
	buffer := make([]byte, 4096)
	bufbytes, err := chunk.Read(buffer)
	if err == io.EOF {
		return err
	}
	file.Write(buffer[:bufbytes])
	return err
}

func ConsumePart(p *multipart.Part, sz int, f func([]byte, int) (interface{}, error)) (interface{}, error) {
	value := make([]byte, sz, sz)
	n, err := p.Read(value)
	if err != nil {
		return nil, err
	}
	i, err := f(value, n)
	if err != nil {
		return nil, err
	}
	return i, err
}

func getParam(part *multipart.Part) (string, float32, error) {
	name := part.FormName()
	fmt.Printf("Read name %s", name)
	if name == "submit" {
		return name, float32(0), nil
	}
	buffer := make([]byte, 1024)
	n, err := part.Read(buffer)
	fmt.Printf("Read %s", string(buffer[:n]))
	if err != nil {
		return "", 0.0, err
	}
	value, err := strconv.ParseFloat(string(buffer[:n]), 32)
	if err != nil {
		return "", 0.0, err
	}
	return name, float32(value), nil
}

func (r *Resumable) ReadBody(p *multipart.Part, c *Chunk) error {
	data := make([]byte, r.MaxChunkSize)
	// read := 0
	// TODO: find a way to identify oversized chunks (read > r.MaxChunkSize?)
	for {
		n, err := p.Read(data)
		// read += n
		if err != nil {
			if err == io.EOF {
				break
			} else {
				return err
			}
		}
		c.Body = append(c.Body, data[:n]...)
	}
	return nil
}

/**
  Uploader has a function to drain an http request off to a filename
  Note that writing to a file is not the only possible course of action.
  The part name (or file name, content type, etc) may insinuate that the file
  is small, and should be held in memory.
*/
func (h uploader) serveHTTPUploadPOSTDrain(fileName string, w http.ResponseWriter, part *multipart.Part) (bytesWritten int64, partsWritten int64) {
	log.Printf("read part %s", fileName)
	//Dangerous... Should whitelist char names to prevent writes
	//outside the homeBucket!
	drainTo, drainErr := os.Create(fileName)
	defer drainTo.Close()

	if drainErr != nil {
		log.Printf("cannot write out file %s, %v", fileName, drainErr)
		http.Error(w, "cannot write out file", 500)
		return bytesWritten, partsWritten
	}

	drain := bufio.NewWriter(drainTo)
	var lastBytesRead int
	buffer := make([]byte, h.BufferSize)
	for lastBytesRead >= 0 {
		bytesRead, berr := part.Read(buffer)
		lastBytesRead = bytesRead
		if berr == io.EOF {
			break
		}
		if berr != nil {
			log.Printf("error reading data! %v", berr)
			http.Error(w, "error reading data", 500)
			return bytesWritten, partsWritten
		}
		if lastBytesRead > 0 {
			bytesWritten += int64(lastBytesRead)
			drain.Write(buffer[:bytesRead])
			partsWritten++
		}
	}
	drain.Flush()
	log.Printf("wrote file %s of length %d", fileName, bytesWritten)
	//Watchout for hardcoding.  This is here to make it convenient to retrieve what you downloaded
	log.Printf("https://127.0.0.1:%d/download/%s", h.Port, fileName[1+len(h.HomeBucket):])

	return bytesWritten, partsWritten
}

func write_file(part *multipart.Part) error {
	dir_name := *dist_dir +
		"/" + time.Now().Format("2006-01-02")
	file_name := dir_name + "/" + part.FileName()
	if err := os.Mkdir(dir_name, 0755); err != nil {
		if os.IsNotExist(err) {
			return err
		}
	}
	if fd, err := os.Open(file_name); err == nil {
		fd.Close()
		return nil
	}
	var err error
	var newfile *os.File
	if newfile, err = os.Create(file_name); err != nil {
		return err
	}
	log.Println("create", file_name)
	defer newfile.Close()
	buf := make([]byte, 1024*1024)
	for {
		n, err := part.Read(buf)
		newfile.Write(buf[:n])
		if err == io.EOF {
			err = nil
			break
		}
		if err != nil {
			os.Remove(file_name)
			log.Print("remove", file_name)
			break
		}
	}
	return err
}

func main() {
	var rr *http.Response
	var myreader multipart.Reader

	syscall.Umask(0000)

	if !parseME() {
		os.Exit(1)
	}

	var requesturl string

	requesturl = ("http://" + (*camera_ip) + ":" + strconv.Itoa(*camera_port) + "/mjpg/1/video.mjpg")
	fmt.Println("request sent to " + requesturl)
	rr, _, _ = http.Get(requesturl)
	myreader, _ = MultipartReader(rr)

	var p *multipart.Part

	var curr_length int = 0

	var templen int
	var buff []byte
	var s string
	var m int

	var info *os.FileInfo
	var err os.Error

	info, err = os.Lstat(*save_folder)
	if err != nil {
		fmt.Println("Folder " + (*save_folder) + " Is problematic")
		fmt.Println(err.String())
		os.Exit(1)
	}

	if !info.IsDirectory() {
		fmt.Println("Folder " + (*save_folder) + " Is not a directory")
		os.Exit(1)
	}

	var foldertime *time.Time = nil
	var foldersecs int64
	var folderstamp string

	var tstamp_secs int64
	var tstamp_nsecs int64

	var msecs int64
	var update bool
	var foldername string
	var imagename string
	var mywriter *os.File

	for i := 0; i < 1; {

		p, _ = myreader.NextPart()

		update = false

		tstamp_secs, tstamp_nsecs, _ = os.Time()
		if foldertime == nil {
			foldertime = time.SecondsToLocalTime(tstamp_secs)
			foldersecs = tstamp_secs
			update = true
		} else {
			if tstamp_secs > foldersecs {
				foldertime = time.SecondsToLocalTime(tstamp_secs)
				foldersecs = tstamp_secs
				update = true
			}

		}

		if update {
			folderstamp = strconv.Itoa64(foldertime.Year) + "_" +
				strconv.Itoa(foldertime.Month) + "_" +
				strconv.Itoa(foldertime.Day) + "_" +
				strconv.Itoa(foldertime.Hour) + "_" +
				strconv.Itoa(foldertime.Minute) + "_" +
				strconv.Itoa(foldertime.Second)
			foldername = (*save_folder) + "/" + (*camera_name) + "_" + folderstamp
			err = os.Mkdir(foldername, 0700)
			if err != nil {
				fmt.Fprintf(os.Stderr, "error creating %s because : %s\n", foldername, err.String())
				os.Exit(1)
			}
		}

		templen, _ = strconv.Atoi(p.Header["Content-Length"])

		if templen > curr_length {
			curr_length = templen
			buff = make([]byte, curr_length)
		}

		for counter := 0; counter < templen; {
			m, _ = p.Read(buff[counter:templen])
			counter += m
		}
//.........这里部分代码省略.........

		matches := boundaryRegexp.FindStringSubmatch(fakeResponseWriter.Header().Get("Content-Type"))
		Expect(matches).To(HaveLen(2))
		Expect(matches[1]).NotTo(BeEmpty())
		reader := multipart.NewReader(fakeResponseWriter.Body, matches[1])
		partsCount := 0
		var err error
		for err != io.EOF {
			var part *multipart.Part
			part, err = reader.NextPart()
			if err == io.EOF {
				break
			}
			partsCount++

			data := make([]byte, 1024)
			n, _ := part.Read(data)
			Expect(data[0:n]).To(Equal([]byte("message")))
		}

		Expect(partsCount).To(Equal(5))
		close(done)
	})

	It("sets the MIME type correctly", func() {
		close(messagesChan)
		r, err := http.NewRequest("GET", "", nil)
		Expect(err).ToNot(HaveOccurred())

		handler.ServeHTTP(fakeResponseWriter, r)
		Expect(fakeResponseWriter.Header().Get("Content-Type")).To(MatchRegexp(`multipart/x-protobuf; boundary=`))
	})