聊天服务器

Posted 2021-02-11 python学习过程

一.实验介绍

1.1 项目目标

本项目使用wxpython、asynchat、_thread等模块开发一个图形界面的聊天室程序。

1.2知识点

• asyncore 、asynchat模块使用
• wxPython 图形开发

1.3项目环境

• Python3.5

 

二.服务器端

首先创建一个聊天服务器类，通过继承asyncore.dispatcher类来实现，创建server.py文件，写入如下代码：

import asynchat
import asyncore

# 定义端口
PORT = 2222

# 定义结束异常类
class EndSession(Exception):
    pass


class ChatServer(asyncore.dispatcher):
    """
    聊天服务器
    """
    def __init__(self, port):
        asyncore.dispatcher.__init__(self)
        # 创建socket
        self.create_socket()
        # 设置 socket 为可重用
        self.set_reuse_addr()
        # 监听端口
        self.bind((‘0.0.0.0‘, port))
        self.listen(5)
        self.users = {}
        self.main_room = ChatRoom(self)

    def handle_accept(self):
        conn, addr = self.accept()
        ChatSession(self, conn)

上述代码完成后，在服务器中还需要能维护每个用户的链接会话，这个功能使用asynchat.async_chat类来实现，在server.py中继续写下如下代码：

class ChatSession(asynchat.async_chat):
    """
   负责和客户端通信
    """

    def __init__(self, server, sock):
        asynchat.async_chat.__init__(self, sock)
        self.server = server
        self.set_terminator(b‘
‘)
        self.data = []
        self.name = None
        self.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.room
        except AttributeError:
            pass
        else:
            cur.remove(self)
        self.room = room
        room.add(self)

    def collect_incoming_data(self, data):
        # 接收客户端的数据
        self.data.append(data.decode("utf-8"))

    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.encode("utf-8"))
        # 退出聊天室的处理
        except EndSession:
            self.handle_close()

    def handle_close(self):
        # 当 session 关闭时，将进入 LogoutRoom
        asynchat.async_chat.handle_close(self)
        self.enter(LogoutRoom(self.server))

接下来实现命令处理类，实现用户的登陆，退出。发消息、查询在线用户的功能,并且使得在房间中的用户类可以继承该命令处理类。在server.py中继续写入如下代码:

class CommandHandler:
    """
    命令处理类
    """
    def unknown(self, session, cmd):
        # 响应未知命令
        # 通过 aynchat.async_chat.push 方法发送消息
        session.push((‘Unknown command {} 
‘.format(cmd)).encode("utf-8"))

    def handle(self, session, line):
        line = line.decode()
        # 命令处理
        if not line.strip():
            return
        parts = line.split(‘ ‘, 1)
        cmd = parts[0]
        try:
            line = parts[1].strip()
        except IndexError:
            line = ‘‘
        # 通过协议代码执行相应的方法
        method = getattr(self, ‘do_‘ + cmd, None)
        try:
            method(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 = server
        self.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
        # 使用 asynchat.asyn_chat.push 方法发送数据
        for session in self.sessions:
            session.push(line)

    def do_logout(self, session, line):
        # 退出房间
        raise EndSession


class LoginRoom(Room):
    """
    处理登录用户
    """
    def add(self, session):
        # 用户连接成功的回应
        Room.add(self, session)
        # 使用 asynchat.asyn_chat.push 方法发送数据
        session.push(b‘Connect Success‘)

    def do_login(self, session, line):
        # 用户登录逻辑
        name = line.strip()
        # 获取用户名称
        if not name:
            session.push(b‘UserName Empty‘)
        # 检查是否有同名用户
        elif name in self.server.users:
            session.push(b‘UserName Exist‘)
        # 用户名检查成功后，进入主聊天室
        else:
            session.name = name
            session.enter(self.server.main_room)


class LogoutRoom(Room):
    """
    处理退出用户
    """
    def add(self, session):
        # 从服务器中移除
        try:
            del self.server.users[session.name]
        except KeyError:
            pass


class ChatRoom(Room):
    """
    聊天用的房间
    """
    def add(self, session):
        # 广播新用户进入
        session.push(b‘Login Success‘)
        self.broadcast((session.name + ‘ has entered the room.
‘).encode("utf-8"))
        self.server.users[session.name] = session
        Room.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.
‘).encode("utf-8"))

    def do_say(self, session, line):
        # 客户端发送消息
        self.broadcast((session.name + ‘: ‘ + line + ‘
‘).encode("utf-8"))

    def do_look(self, session, line):
        # 查看在线用户
        session.push(b‘Online Users:
‘)
        for other in self.sessions:
            session.push((other.name + ‘
‘).encode("utf-8"))

在server.py的最下民输入如下代码，启动server端。

if __name__ == ‘__main__‘:
    s = ChatServer(PORT)
    try:
        print("chat serve run at ‘127.0.0.1:{0}‘".format(PORT))
        asyncore.loop()
    except KeyboardInterrupt:
        print("chat server exit")

 

三.客户端

完成了服务器端后，就需要实现客户端了。客户端将基于 wxPython 模块实现。 wxPython 模块是 wxWidgets GUI 工具的 Python 绑定。所以通过 wxPython 模块我们就可以实现 GUI 编程了。同时我们的聊天协议基于文本，所以我们和服务器之间的通信将基于 telnetlib 模块实现。代码如下：

import telnetlib,wx
from time import sleep
import _thread as thread


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))
        # 绑定登录方法
        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 != b‘Connect Success‘:
                self.showDialog(‘Error‘, ‘Connect Fail!‘, (200, 100))
                return
            con.write((‘login ‘ + str(self.userName.GetLineText(0)) + ‘
‘).encode("utf-8"))
            response = con.read_some()
            if response == b‘UserName Empty‘:
                self.showDialog(‘Error‘, ‘UserName Empty!‘, (200, 100))
            elif response == b‘UserName Exist‘:
                self.showDialog(‘Error‘, ‘UserName Exist!‘, (200, 100))
            else:
                self.Close()
                ChatFrame(None, 2, title=‘ShiYanLou Chat Client‘, size=(500, 400))
        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))
        # 发送按钮绑定发送消息方法
        self.sendButton.Bind(wx.EVT_BUTTON, self.send)
        # Users按钮绑定获取在线用户数量方法
        self.usersButton.Bind(wx.EVT_BUTTON, self.lookUsers)
        # 关闭按钮绑定关闭方法
        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 + ‘
‘).encode("utf-8"))
            self.message.Clear()

    def lookUsers(self, event):
        # 查看当前在线用户
        con.write(b‘look
‘)


    def close(self, event):
        # 关闭窗口
        con.write(b‘logout
‘)
        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)


if __name__ == ‘__main__‘:
    app = wx.App()
    con = telnetlib.Telnet()
    LoginFrame(None, -1, title="Login", size=(320, 250))
    app.MainLoop()