用socket实现一个即时通讯程序 要求实现私聊 群聊 发送文件功能

以下是一个基于Python的简单即时通讯程序，包括私聊、群聊和发送文件功能。其中，使用了socket和select模块。

服务端代码：

import socket
import select
import os

# 创建TCP套接字
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

# 设置地址复用
server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

# 绑定地址和端口
server_socket.bind(('localhost', 8000))

# 监听客户端连接
server_socket.listen(5)

# 存储客户端套接字对象和昵称的字典
clients = {}

print('Server is running...')

while True:
    # 监听套接字和客户端套接字列表
    sockets_list = [server_socket] + list(clients.keys())

    # 使用select模块监听套接字
    read_sockets, _, _ = select.select(sockets_list, [], [])

    for sock in read_sockets:
        # 如果是服务器套接字，表示有新的客户端连接
        if sock == server_socket:
            client_socket, client_address = server_socket.accept()

            # 发送欢迎消息
            client_socket.send(b'Welcome to the chatroom! Please enter your nickname: ')

        # 如果是客户端套接字，表示有消息发送过来
        else:
            # 接收消息
            try:
                message = sock.recv(1024)

                # 如果客户端断开连接
                if not message:
                    # 关闭套接字并从字典中删除
                    sock.close()
                    del clients[sock]
                    continue

                # 如果客户端还没有设置昵称
                if sock not in clients:
                    nickname = message.decode('utf-8').strip()

                    # 如果昵称已经存在
                    if nickname in clients.values():
                        sock.send(b'This nickname is already taken. Please enter another one: ')
                        continue

                    clients[sock] = nickname

                    # 发送欢迎消息
                    message = f'{nickname} has joined the chatroom!\n'.encode('utf-8')

                else:
                    message = message.decode('utf-8')

                # 判断是否是私聊
                if message.startswith('@'):
                    dest_nickname, message = message.split(' ', 1)
                    dest_sock = None

                    # 查找目标客户端套接字
                    for sock, nickname in clients.items():
                        if nickname == dest_nickname[1:]:
                            dest_sock = sock
                            break

                    # 如果目标客户端不存在
                    if not dest_sock:
                        sock.send(f'{dest_nickname[1:]} is not online.\n'.encode('utf-8'))
                        continue

                    # 发送私聊消息
                    message = f'{clients[sock]} (private): {message}'
                    message = message.encode('utf-8')
                    dest_sock.send(message)
                    continue

                # 判断是否是发送文件
                if message.startswith('#'):
                    dest_nickname, filename = message.split(' ', 1)
                    dest_sock = None

                    # 查找目标客户端套接字
                    for sock, nickname in clients.items():
                        if nickname == dest_nickname[1:]:
                            dest_sock = sock
                            break

                    # 如果目标客户端不存在
                    if not dest_sock:
                        sock.send(f'{dest_nickname[1:]} is not online.\n'.encode('utf-8'))
                        continue

                    # 发送文件
                    try:
                        with open(filename.strip(), 'rb') as f:
                            data = f.read()

                        message = f'{clients[sock]} (file): {filename}'
                        message = message.encode('utf-8')
                        dest_sock.send(message)
                        dest_sock.send(data)
                    except:
                        sock.send(f'Failed to send file "{filename.strip()}".\n'.encode('utf-8'))

                    continue

                # 发送群聊消息
                message = f'{clients[sock]}: {message}'
                message = message.encode('utf-8')

                for client_sock in clients.keys():
                    if client_sock != sock:
                        client_sock.send(message)

            # 如果出现异常，关闭套接字并从字典中删除
            except:
                sock.close()
                del clients[sock]

# 关闭服务器套接字
server_socket.close()

客户端代码：

import socket
import threading
import os

# 创建TCP套接字
client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

# 连接服务器
client_socket.connect(('localhost', 8000))

# 接收欢迎消息并设置昵称
nickname = input(client_socket.recv(1024).decode('utf-8'))
client_socket.send(nickname.encode('utf-8'))

# 接收消息的函数
def receive():
    while True:
        try:
            message = client_socket.recv(1024).decode('utf-8')
            print(message)
        except:
            print('An error occurred!')
            client_socket.close()
            break

# 发送消息的函数
def send():
    while True:
        message = input()

        # 判断是否是退出命令
        if message == '/quit':
            client_socket.close()
            break

        # 判断是否是私聊
        if message.startswith('@'):
            dest_nickname, message = message.split(' ', 1)
            message = message.encode('utf-8')
            message = '@' + dest_nickname[1:] + ' ' + message
            client_socket.send(message)
            continue

        # 判断是否是发送文件
        if message.startswith('#'):
            filename = message.split(' ', 1)[1].strip()

            # 判断文件是否存在
            if not os.path.exists(filename):
                print(f'The file "{filename}" does not exist!')
                continue

            message = '#' + nickname + ' ' + filename
            message = message.encode('utf-8')
            client_socket.send(message)

            try:
                with open(filename, 'rb') as f:
                    data = f.read()

                client_socket.send(data)
                print(f'The file "{filename}" has been sent successfully!')
            except:
                print(f'Failed to send file "{filename}".')
            continue

        # 发送群聊消息
        message = message.encode('utf-8')
        client_socket.send(message)

# 启动接收消息的线程和发送消息的线程
receive_thread = threading.Thread(target=receive)
send_thread = threading.Thread(target=send)

receive_thread.start()
send_thread.start()

使用方法：

1. 分别运行服务端代码和客户端代码。

2. 客户端会提示输入昵称，输入后回车即可。

3. 客户端可以输入消息发送给所有客户端，也可以使用@昵称指定私聊某个客户端。

4. 客户端可以使用#文件名发送文件给其他客户端。客户端发送文件时，服务端会先发送一条消息，包括发送者的昵称和文件名，然后再发送文件内容。接收到文件的客户端会自动保存文件到当前目录下。

5. 客户端可以使用/quit命令退出程序。