class SpockDataIntegrationDownloadHandler(tornado.web.RequestHandler):    def post(self):        selectname = self.get_argument('selectname')        json_string = {}        """        将请求参数放到dict中        """          type = self.get_argument('type')          starttime = self.get_argument('starttime')          endtime = self.get_argument('end_time')          json_string['starttime'] = starttime          json_string['endtime'] = endtime          json_string['type'] = type          """        生成json文件        """        if json_string:          filepath = './jsonfile.conf'          if os.path.exists(filepath):            os.remove(filepath)          ff = open(filepath, 'w')          json.dump(json_string, ff)  # 将json格式数据写入文件          ff.close()          """          下载文件          """          filename = "jsonfile.conf"          self.set_header ('Content-Type', 'application/octet-stream')          self.set_header ('Content-Disposition', 'attachment; filename=' + filename)          buf_size = 4096          with open(os.path.join('',filepath), 'rb') as f:            while True:              data = f.read(buf_size)              if not data:                break              self.write(data)          self.finish()