func main() { mux := http.NewServeMux() //在这里分别把下载、上传、range查询的处理函数进行映射绑定 mux.HandleFunc("/download", handlerdownload) mux.HandleFunc("/upload", handlerupload) mux.HandleFunc("/range", handlerrange) server := &http.Server{ Addr: ":8080"...-DPDK中文网

当客户端发起对/range路径的请求时，可以在handlerrange函数中实现支持范围下载功能。以下是一个简单的示例代码：

func handlerrange(w http.ResponseWriter, r *http.Request) {
	// 获取要处理的文件路径
	filePath := "/path/to/file.ext"

	// 打开文件
	file, err := os.Open(filePath)
	if err != nil {
		http.Error(w, "Failed to open file", http.StatusInternalServerError)
		return
	}
	defer file.Close()

	// 获取文件信息
	fileInfo, err := file.Stat()
	if err != nil {
		http.Error(w, "Failed to get file info", http.StatusInternalServerError)
		return
	}

	// 获取请求头中的Range字段值
	rangeHeader := r.Header.Get("Range")
	if rangeHeader == "" {
		http.Error(w, "Missing Range header", http.StatusBadRequest)
		return
	}

	var start, end int64

	if strings.HasPrefix(rangeHeader, "bytes=") {
		rangeValue := strings.TrimPrefix(rangeHeader, "bytes=")

		byteRangeParts := strings.SplitN(rangeValue, "-", 2)

		startStr := byteRangeParts[0]
		endStr := byteRangeParts[1]

    // 处理start和end值为空情况（例如：bytes=100- 或 bytes=-500）
    if startStr == "" && endStr != "" {
        end, _ = strconv.ParseInt(endStr, 10, 64)
        start = fileInfo.Size() - end
        end = fileInfo.Size() - 1
    } else if startStr != "" && endStr == "" {
        start, _ = strconv.ParseInt(startStr, 10, 64)
        end = fileInfo.Size() - 1
    } else {
        start, _ = strconv.ParseInt(startStr, 10, 64)
        end, _ = strconv.ParseInt(endStr, 10, 64)
    }

		// 设置Content-Range响应头
		w.Header().Set("Content-Range", fmt.Sprintf("bytes %d-%d/%d", start, end, fileInfo.Size()))
	} else {
		http.Error(w, "Invalid Range header", http.StatusBadRequest)
		return
	}

	contentLength := end - start + 1

	// 设置Content-Length和Content-Type响应头
	w.Header().Set("Content-Length", strconv.FormatInt(contentLength, 10))
	w.Header().Set("Content-Type", "application/octet-stream")

	buffer := make([]byte, 1024)

	_, err = file.Seek(start, io.SeekStart)
	if err != nil {
		http.Error(w, "Failed to seek file", http.StatusInternalServerError)
		return
	}

	for remainingBytes := contentLength; remainingBytes > 0; {
		numBytesToRead := int64(len(buffer))
		if remainingBytes < numBytesToRead {
			numBytesToRead = remainingBytes
		}

		numBytesRead, err := file.Read(buffer[:numBytesToRead])
		if err != nil && err != io.EOF {
			http.Error(w, "Failed to read from file", http.StatusInternalServerError)
			return
        }

        if numBytesRead == 0 {
            break
        }

        w.Write(buffer[:numBytesRead])
        remainingBytes -= int64(numBytesRead)
    }
}

请注意，上述代码只是一个简单的示例，你可能需要根据具体情况进行修改和完善。

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