docs: @ResponseBody
      @RequestMapping(value = "/file", method = RequestMethod.POST)
      public JsonObjectBase updateFile(@Valid ConfNewForm confNewForm, @RequestParam("myfilerar") MultipartFile file) {
  
          LOG.info(confNewForm.toString());
  
          //
          // 校验
          //
          int fileSize = 1024 * 1024 * 4;
          String[] allowExtName = {".properties", ".xml"};
          fileUploadValidator.validateFile(file, fileSize, allowExtName);
  
          //
          // 更新
          //
          String fileContent = "";
          try {
  
              fileContent = new String(file.getBytes(), "UTF-8");
              LOG.info("receive file: " + fileContent);
  
          } catch (Exception e) {
  
              LOG.error(e.toString());
              throw new FileUploadException("upload file error", e);
          }
  
          // 创建配置文件表格
          ConfNewItemForm confNewItemForm = new ConfNewItemForm(confNewForm);
          confNewItemForm.setKey(file.getOriginalFilename());
          confNewItemForm.setValue(fileContent);
  
          // 业务校验
          configValidator.validateNew(confNewItemForm, DisConfigTypeEnum.FILE);
  
          //
          configMgr.newConfig(confNewItemForm, DisConfigTypeEnum.FILE);
  
          return buildSuccess("创建成功");
      }