本课程来自实验楼Python聊天室，若需转载请注明原文出处。

一、课程介绍

1.简介

本次项目课是实现简单聊天室程序的服务器端和客户端。

2.知识点

服务器端涉及到asyncore、asynchat和socket这几个模块，客户端用到了telnetlib、wx、time和thread这几个模块。

3.所需环境

本次课中编写客户端需要用到wxPython，它是一个GUI工具包，请先使用下面的命令安装：

$ sudo apt-get install python-wxtools

密码为shiyanlou

4.项目效果截图

登录窗口

聊天窗口

5.源代码下载

git clone https://github.com/shiyanlou/pythonchat.git

说明：如果你不理解上述代码的下载方式或者下载后在环境中找不到代码，可以点击查看这里

二、项目实战（服务器端）

1.服务器类

首先需要一个聊天服务器，这里继承asyncore的dispatcher类来实现，代码如下

class ChatServer(dispatcher):"""聊天服务器"""def __init__(self, port):dispatcher.__init__(self)self.create_socket(socket.AF_INET, socket.SOCK_STREAM)self.set_reuse_addr()self.bind(('', port))self.listen(5)self.users = {}self.main_room = ChatRoom(self)def handle_accept(self):conn, addr = self.accept()ChatSession(self, conn)

2.会话类

有了服务器类还需要能维护每个用户的连接会话，这里继承asynchat的async_chat类来实现，代码如下：

class ChatSession(async_chat):"""负责和单用户通信"""def __init__(self, server, sock):async_chat.__init__(self, sock)self.server = serverself.set_terminator('\n')self.data = []self.name = Noneself.enter(LoginRoom(server))def enter(self, room):'从当前房间移除自身，然后添加到指定房间'try:cur = self.roomexcept AttributeError:passelse:cur.remove(self)self.room = roomroom.add(self)def collect_incoming_data(self, data):'接受客户端的数据'self.data.append(data)def found_terminator(self):'当客户端的一条数据结束时的处理'line = ''.join(self.data)self.data = []try:self.room.handle(self, line)except EndSession:self.handle_close()def handle_close(self):async_chat.handle_close(self)self.enter(LogoutRoom(self.server))

3.命令解释器

现在就需要一个命令解释器能够解释用户的命令，例如登录、查询在线用户和发消息等，代码如下：

class CommandHandler:"""命令处理类"""def unknown(self, session, cmd):'响应未知命令'session.push('Unknown command: %s\n' % cmd)def handle(self, session, line):'命令处理'if not line.strip():returnparts = line.split(' ', 1)cmd = parts[0]try:line = parts[1].strip()except IndexError:line = ''meth = getattr(self, 'do_' + cmd, None)try:meth(session, line)except TypeError:self.unknown(session, cmd)

4.房间

接下来就需要实现聊天室的房间了，这里我们定义了三种房间，分别是用户刚登录时的房间、聊天的房间和退出登录的房间，这三种房间都有一个公共的父类，代码如下：

class Room(CommandHandler):"""包含多个用户的环境，负责基本的命令处理和广播"""def __init__(self, server):self.server = serverself.sessions = []def add(self, session):'一个用户进入房间'self.sessions.append(session)def remove(self, session):'一个用户离开房间'self.sessions.remove(session)def broadcast(self, line):'向所有的用户发送指定消息'for session in self.sessions:session.push(line)def do_logout(self, session, line):'退出房间'raise EndSessionclass LoginRoom(Room):"""刚登录的用户的房间"""def add(self, session):'用户连接成功的回应'Room.add(self, session)session.push('Connect Success')def do_login(self, session, line):'登录命令处理'name = line.strip()if not name:session.push('UserName Empty')elif name in self.server.users:session.push('UserName Exist')else:session.name = namesession.enter(self.server.main_room)class ChatRoom(Room):"""聊天用的房间"""def add(self, session):'广播新用户进入'session.push('Login Success')self.broadcast(session.name + ' has entered the room.\n')self.server.users[session.name] = sessionRoom.add(self, session)def remove(self, session):'广播用户离开'Room.remove(self, session)self.broadcast(session.name + ' has left the room.\n')def do_say(self, session, line):'客户端发送消息'self.broadcast(session.name + ': ' + line + '\n')def do_look(self, session, line):'查看在线用户'session.push('Online Users:\n')for other in self.sessions:session.push(other.name + '\n')class LogoutRoom(Room):"""用户退出时的房间"""def add(self, session):'从服务器中移除'try:del self.server.users[session.name]except KeyError:pass

5.服务器端完整代码

#!/usr/bin/python
# encoding: utf-8from asyncore import dispatcher
from asynchat import async_chat
import socket, asyncorePORT = 6666 #端口class EndSession(Exception):"""自定义会话结束时的异常"""passclass CommandHandler:"""命令处理类"""def unknown(self, session, cmd):'响应未知命令'session.push('Unknown command: %s\n' % cmd)def handle(self, session, line):'命令处理'if not line.strip():returnparts = line.split(' ', 1)cmd = parts[0]try:line = parts[1].strip()except IndexError:line = ''meth = getattr(self, 'do_' + cmd, None)try:meth(session, line)except TypeError:self.unknown(session, cmd)class Room(CommandHandler):"""包含多个用户的环境，负责基本的命令处理和广播"""def __init__(self, server):self.server = serverself.sessions = []def add(self, session):'一个用户进入房间'self.sessions.append(session)def remove(self, session):'一个用户离开房间'self.sessions.remove(session)def broadcast(self, line):'向所有的用户发送指定消息'for session in self.sessions:session.push(line)def do_logout(self, session, line):'退出房间'raise EndSessionclass LoginRoom(Room):"""刚登录的用户的房间"""def add(self, session):'用户连接成功的回应'Room.add(self, session)session.push('Connect Success')def do_login(self, session, line):'登录命令处理'name = line.strip()if not name:session.push('UserName Empty')elif name in self.server.users:session.push('UserName Exist')else:session.name = namesession.enter(self.server.main_room)class ChatRoom(Room):"""聊天用的房间"""def add(self, session):'广播新用户进入'session.push('Login Success')self.broadcast(session.name + ' has entered the room.\n')self.server.users[session.name] = sessionRoom.add(self, session)def remove(self, session):'广播用户离开'Room.remove(self, session)self.broadcast(session.name + ' has left the room.\n')def do_say(self, session, line):'客户端发送消息'self.broadcast(session.name + ': ' + line + '\n')def do_look(self, session, line):'查看在线用户'session.push('Online Users:\n')for other in self.sessions:session.push(other.name + '\n')class LogoutRoom(Room):"""用户退出时的房间"""def add(self, session):'从服务器中移除'try:del self.server.users[session.name]except KeyError:passclass ChatSession(async_chat):"""负责和单用户通信"""def __init__(self, server, sock):async_chat.__init__(self, sock)self.server = serverself.set_terminator('\n')self.data = []self.name = Noneself.enter(LoginRoom(server))def enter(self, room):'从当前房间移除自身，然后添加到指定房间'try:cur = self.roomexcept AttributeError:passelse:cur.remove(self)self.room = roomroom.add(self)def collect_incoming_data(self, data):'接受客户端的数据'self.data.append(data)def found_terminator(self):'当客户端的一条数据结束时的处理'line = ''.join(self.data)self.data = []try:self.room.handle(self, line)except EndSession:self.handle_close()def handle_close(self):async_chat.handle_close(self)self.enter(LogoutRoom(self.server))class ChatServer(dispatcher):"""聊天服务器"""def __init__(self, port):dispatcher.__init__(self)self.create_socket(socket.AF_INET, socket.SOCK_STREAM)self.set_reuse_addr()self.bind(('', port))self.listen(5)self.users = {}self.main_room = ChatRoom(self)def handle_accept(self):conn, addr = self.accept()ChatSession(self, conn)if __name__ == '__main__':s = ChatServer(PORT)try:asyncore.loop()except KeyboardInterrupt:print

三、项目实战（客户端）

完成了服务器端后，就需要实现客户端了，这里客户端连接服务器使用了telnetlib模块。

1.登录窗口

这里的图形界面包选择了wxPython，前面有安装说明，登录窗口通过继承wx.Frame类来实现，代码如下：

class LoginFrame(wx.Frame):"""登录窗口"""def __init__(self, parent, id, title, size):'初始化，添加控件并绑定事件'wx.Frame.__init__(self, parent, id, title)self.SetSize(size)self.Center()self.serverAddressLabel = wx.StaticText(self, label = "Server Address", pos = (10, 50), size = (120, 25))self.userNameLabel = wx.StaticText(self, label = "UserName", pos = (40, 100), size = (120, 25))self.serverAddress = wx.TextCtrl(self, pos = (120, 47), size = (150, 25))self.userName = wx.TextCtrl(self, pos = (120, 97), size = (150, 25))self.loginButton = wx.Button(self, label = 'Login', pos = (80, 145), size = (130, 30))self.loginButton.Bind(wx.EVT_BUTTON, self.login)self.Show()def login(self, event):'登录处理'try:serverAddress = self.serverAddress.GetLineText(0).split(':')con.open(serverAddress[0], port = int(serverAddress[1]), timeout = 10)response = con.read_some()if response != 'Connect Success':self.showDialog('Error', 'Connect Fail!', (95, 20))returncon.write('login ' + str(self.userName.GetLineText(0)) + '\n')response = con.read_some()if response == 'UserName Empty':self.showDialog('Error', 'UserName Empty!', (135, 20))elif response == 'UserName Exist':self.showDialog('Error', 'UserName Exist!', (135, 20))else:self.Close()ChatFrame(None, -2, title = 'ShiYanLou Chat Client', size = (500, 350))except Exception:self.showDialog('Error', 'Connect Fail!', (95, 20))def showDialog(self, title, content, size):'显示错误信息对话框'dialog = wx.Dialog(self, title = title, size = size)dialog.Center()wx.StaticText(dialog, label = content)dialog.ShowModal()

2.聊天窗口

聊天窗口中最主要的就是向服务器发消息并接受服务器的消息，这里通过子线程来接受，代码如下：

class ChatFrame(wx.Frame):"""聊天窗口"""def __init__(self, parent, id, title, size):'初始化，添加控件并绑定事件'wx.Frame.__init__(self, parent, id, title)self.SetSize(size)self.Center()self.chatFrame = wx.TextCtrl(self, pos = (5, 5), size = (490, 310), style = wx.TE_MULTILINE | wx.TE_READONLY)self.message = wx.TextCtrl(self, pos = (5, 320), size = (300, 25))self.sendButton = wx.Button(self, label = "Send", pos = (310, 320), size = (58, 25))self.usersButton = wx.Button(self, label = "Users", pos = (373, 320), size = (58, 25))self.closeButton = wx.Button(self, label = "Close", pos = (436, 320), size = (58, 25))self.sendButton.Bind(wx.EVT_BUTTON, self.send)self.usersButton.Bind(wx.EVT_BUTTON, self.lookUsers)self.closeButton.Bind(wx.EVT_BUTTON, self.close)thread.start_new_thread(self.receive, ())self.Show()def send(self, event):'发送消息'message = str(self.message.GetLineText(0)).strip()if message != '':con.write('say ' + message + '\n')self.message.Clear()def lookUsers(self, event):'查看当前在线用户'con.write('look\n')def close(self, event):'关闭窗口'con.write('logout\n')con.close()self.Close()def receive(self):'接受服务器的消息'while True:sleep(0.6)result = con.read_very_eager()if result != '':self.chatFrame.AppendText(result)

3.客户端完整代码

#!/usr/bin/python
# encoding: utf-8import wx
import telnetlib
from time import sleep
import threadclass LoginFrame(wx.Frame):"""登录窗口"""def __init__(self, parent, id, title, size):'初始化，添加控件并绑定事件'wx.Frame.__init__(self, parent, id, title)self.SetSize(size)self.Center()self.serverAddressLabel = wx.StaticText(self, label = "Server Address", pos = (10, 50), size = (120, 25))self.userNameLabel = wx.StaticText(self, label = "UserName", pos = (40, 100), size = (120, 25))self.serverAddress = wx.TextCtrl(self, pos = (120, 47), size = (150, 25))self.userName = wx.TextCtrl(self, pos = (120, 97), size = (150, 25))self.loginButton = wx.Button(self, label = 'Login', pos = (80, 145), size = (130, 30))self.loginButton.Bind(wx.EVT_BUTTON, self.login)self.Show()def login(self, event):'登录处理'try:serverAddress = self.serverAddress.GetLineText(0).split(':')con.open(serverAddress[0], port = int(serverAddress[1]), timeout = 10)response = con.read_some()if response != 'Connect Success':self.showDialog('Error', 'Connect Fail!', (95, 20))returncon.write('login ' + str(self.userName.GetLineText(0)) + '\n')response = con.read_some()if response == 'UserName Empty':self.showDialog('Error', 'UserName Empty!', (135, 20))elif response == 'UserName Exist':self.showDialog('Error', 'UserName Exist!', (135, 20))else:self.Close()ChatFrame(None, -2, title = 'ShiYanLou Chat Client', size = (500, 350))except Exception:self.showDialog('Error', 'Connect Fail!', (95, 20))def showDialog(self, title, content, size):'显示错误信息对话框'dialog = wx.Dialog(self, title = title, size = size)dialog.Center()wx.StaticText(dialog, label = content)dialog.ShowModal()class ChatFrame(wx.Frame):"""聊天窗口"""def __init__(self, parent, id, title, size):'初始化，添加控件并绑定事件'wx.Frame.__init__(self, parent, id, title)self.SetSize(size)self.Center()self.chatFrame = wx.TextCtrl(self, pos = (5, 5), size = (490, 310), style = wx.TE_MULTILINE | wx.TE_READONLY)self.message = wx.TextCtrl(self, pos = (5, 320), size = (300, 25))self.sendButton = wx.Button(self, label = "Send", pos = (310, 320), size = (58, 25))self.usersButton = wx.Button(self, label = "Users", pos = (373, 320), size = (58, 25))self.closeButton = wx.Button(self, label = "Close", pos = (436, 320), size = (58, 25))self.sendButton.Bind(wx.EVT_BUTTON, self.send)self.usersButton.Bind(wx.EVT_BUTTON, self.lookUsers)self.closeButton.Bind(wx.EVT_BUTTON, self.close)thread.start_new_thread(self.receive, ())self.Show()def send(self, event):'发送消息'message = str(self.message.GetLineText(0)).strip()if message != '':con.write('say ' + message + '\n')self.message.Clear()def lookUsers(self, event):'查看当前在线用户'con.write('look\n')def close(self, event):'关闭窗口'con.write('logout\n')con.close()self.Close()def receive(self):'接受服务器的消息'while True:sleep(0.6)result = con.read_very_eager()if result != '':self.chatFrame.AppendText(result)'程序运行'
if __name__ == '__main__':app = wx.App()con = telnetlib.Telnet()LoginFrame(None, -1, title = "Login", size = (280, 200))app.MainLoop()

四、小结

最后就可以运行程序进行聊天了，注意需要先启动服务器再启动客户端。这个项目中使用了asyncore的dispatcher来实现服务器，asynchat的asyn_chat来维护用户的连接会话，用wxPython来实现图形界面，用telnetlib来连接服务器，在子线程中接受服务器发来的消息，由此一个简单的聊天室程序就完成了。