读取请求,并转化为python的字典结构.如果读入了EOF,那么触发回调函数connection_lost.

async def read(self):
        """读取请求,并转化为python的字典结构.如果读入了EOF,那么触发回调函数connection_lost."""
        try:
            data = await self._stream_reader.readuntil(self.SEPARATOR)
        except asyncio.IncompleteReadError:
            self.connection_lost()
        else:
            query = self.decoder(data)
            if self.debug:
                access_logger.info("get query: {}".format(
                    query
                ), extra=self._extra)
            return query