关于tornado异步tcp的问题

Question

大家好! 我有一段tornado异步tcp服务器的代码,tcp服务器向客户端发送命令,遇到一些问题. #! /usr/bin/env python #coding=utf-8 from tornado.tcpserver import TCPServer from tornado.ioloop import IOLoop from ctypes import * import struct from const import * from systemModel import * class TcpConnection(object): def __init__(self,stream,address): self._stream=stream self._address=address self._stream.set_close_callback(self.on_close) self.getSystemInfo() self.getSystemInfo() def on_close(self): print("the monitored %d has left",self._address) def getSystemInfo(self): commandType=Command.SYSTEMINFO commandInfo=Command.NOCOMMANDINFO data=struct.pack(FormatStr.COMMANDINFO,commandType,commandInfo.encode('utf-8')) self._stream.write(data) self._stream.read_bytes(SystemInfo.len_whole,setSystemInfo) class MonitorServer(TCPServer): def handle_stream(self,stream,address): print("new connection",address,stream) TcpConnection(stream,address) if __name__=='__main__': print('server start .....') server=MonitorServer() server.listen(20000) IOLoop.instance().start() 上面有2个self.getSystemInfo(),我的意思是想,能否一下丢出几个命令,比如传文件,传信息等.但是上面的代码会报错.错误信息如下: ERROR:tornado.application:Error in connection callback Traceback (most recent call last): File "/usr/local/lib/python3.4/dist-packages/tornado/tcpserver.py", line 269, in _handle_connection future = self.handle_stream(stream, address) File "/home/zz/PycharmProjects/monitor/server.py", line 64, in handle_stream TcpConnection(stream,address) File "/home/zz/PycharmProjects/monitor/server.py", line 18, in __init__ self.getSystemInfo() File "/home/zz/PycharmProjects/monitor/server.py", line 32, in getSystemInfo self._stream.read_bytes(SystemInfo.len_whole,setSystemInfo) File "/usr/local/lib/python3.4/dist-packages/tornado/iostream.py", line 303, in read_bytes future = self._set_read_callback(callback) File "/usr/local/lib/python3.4/dist-packages/tornado/iostream.py", line 658, in _set_read_callback assert self._read_callback is None, "Already reading" AssertionError: Already reading 这个错误信息,是不是前一个self.getSystemInfo()还没读完,后一个self.getSystemInfo()就要开始读了?我要怎样去解决这样的冲突呢