Python项目五: 虚拟茶话会

代码地址：https://code.youkuaiyun.com/ranky2009/pythonsmallproject

本文分析并实现Python基础教程中的项目五。

由于运行平台是win7,使用telnet来测试python代码
Win7需要启动telnet服务,开始->控制面板->程序和功能->打开或关闭Windows功能->勾选“Telnet服务器”，“Telnet客户端”->确定，安装服务(安装Telnet客户端就可以了)
 
启动一个cmd，输入telnet，可以进入telnet服务
输入quit可以退出服务。

代码1:

from asyncore import dispatcher
from asynchat import async_chat
import asyncore, socket

PORT = 5005#端口号 
NAME = 'TestChat'#自定义聊天中心名称 

class ChatSession(async_chat):
    '''
    Session类， 记录客户端发送来的内容
    '''
    def __init__(self, server, sock):
        async_chat.__init__(self, sock)#初始化父类
        self.server = server#记录session的服务器
        self.set_terminator(("\r\n").encode())#设置触发found_terminator条件
        self.data = []
        welcome = 'Welcome to %s\r\n' % self.server.name
        self.push(welcome.encode())#压入欢迎字符串

    def collect_incoming_data(self, data):
        self.data.append(data.decode())

    def found_terminator(self):
        #触发该函数时，调用服务器函数发送数据给客户端

        line = ''.join(self.data)
        self.data = []
        self.server.broadcast(line)

    def handle_close(self):
        async_chat.handle_close(self)
        self.server.disconnect(self)
        
class ChatServer(dispatcher):
    def __init__(self, port, name):
        dispatcher.__init__(self)
        self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
        self.set_reuse_addr()
        self.bind(('', port))
        self.name = name
        self.listen(5)
        self.sessions = []

    def disconnect(self, session):
        #移除指定的session
        self.sessions.remove(session)

    def broadcast(self, line):
        #向每个客户端发送消息
        for session in self.sessions:
            session.push((line + '\r\n').encode())
            
    def handle_accept(self):
        #当客户端连接该端口的时候运行此函数
        conn, addr = self.accept()#同意连接
        print('Connnetion attempt from', addr[0])#打印客户端地址
        self.sessions.append(ChatSession(self, conn))#创建客户与服务器之间session

if __name__=='__main__':
    s = ChatServer(PORT, NAME)
    try: asyncore.loop()
    except KeyboardInterrupt: print()

运行以上代码，然后再开一个cmd，先输入telnet进入telnet客户端，在输入open localhost 5005, 连接刚才服务器，输入数据后回车，会发现客户端返回相同的消息，开多个cmd，并连接服务器，所有客户端都会收到该消息。

上面的代码有没区分消息发送端和接收端，完善代码，使该程序在多个客户端之间，区分发送的客户端与接受客户端，代码如下：

from asyncore import dispatcher
from asynchat import async_chat
import socket, asyncore

PORT = 5005
NAME = 'TestChat'

class EndSession(Exception): pass

class CommandHandler:
	def unknown(self, session, cmd):
		session.push(('Unknown command: %s\r\n' % cmd).encode())

	def handle(self, session, line):
		if not line.strip(): return
		parts = 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):
	def __init__(self, server):
		self.server = server
		self.sessions = []
		
	def add(self, session):
		self.sessions.append(session)
	
	def remove(self, session):
		self.sessions.remove(session)
		
	def broadcast(self, line):
		for session in self.sessions:
			session.push(line.encode())
			
	def do_logout(self, session, line):
		raise EndSession

class LoginRoom(Room):
	def add(self, session):
		Room.add(self, session)
		self.broadcast('Welcome to %s\r\n' % self.server.name)
		
	def unknown(self, session, cmd):
		session.push(('Please log in\nUse "login <nick>"\r\n').encode())
		
	def do_login(self, session, line):
		name = line.strip()
		if not name:
			session.push(('Please enter a name\r\n').encode())
		elif name in self.server.users:
			session.push(('The name "%s" is taken.\r\n' % name).encode())
			session.push(('Please try again.\r\n').encode())
		else:
			session.name = name
			session.enter(self.server.main_room)
			
class ChatRoom(Room):
	def add(self, session):
		self.broadcast(session.name + ' has entered the room.\r\n')
		self.server.users[session.name] = session
		Room.add(self, session)
	
	def remove(self, session):
		Room.remove(self, session)
		self.broadcast(session.name + ' has left the room.\r\n')
		
	def do_say(self, session, line):
		self.broadcast(session.name + ': ' + line + '\r\n')
	
	def do_look(self, session, line):
		session.push(('The following are in this room:\r\n').encode())
		for other in self.sessions:
			session.push((other.name + '\r\n').encode())
			
	def do_who(self, session, line):
		session.push(('The following are in this room:\r\n').encode())
		for name in self.server.users:
			session.push(((name + '\r\n').encode()).encode())
			
class LogoutRoom(Room):
	def add(self, session):
		try: del self.server.users[session.name]
		except KeyError: pass
		
class ChatSession(async_chat):
	def __init__(self, server, sock):
		async_chat.__init__(self, sock)
		self.server = server
		self.set_terminator(('\r\n').encode())
		self.data = []
		self.name = None
		self.enter(LoginRoom(server))
		
	def enter(self, room):
		try: cur = self.room
		except AttributeError: pass
		else: cur.remove(self)
		self.room = room
		room.add(self)
		
	def collect_incoming_data(self, data):
		self.data.append(data.decode())
		
	def found_terminator(self):
		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):
	def __init__(self, port, name):
		dispatcher.__init__(self)
		self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
		self.set_reuse_addr()
		self.bind(('', port))
		self.listen(5)
		self.name = name
		self.users = {}
		self.main_room = ChatRoom(self)
		
	def handle_accept(self):
		conn, addr = self.accept()
		ChatSession(self, conn)
		
if __name__ == '__main__':
	s = ChatServer(PORT, NAME)
	try: asyncore.loop()
	except KeyboardInterrupt: print()

启动cmd，输入telnet，然后链接服务器open localhost 5005。

登录键入login XXX（XXX为用户名，任意值），发送消息say XXX，who或者look命令查看在此chatroom中的所有用户。