Question

我已经编写了一个服务器和一个客户端，如果我关闭客户端并再次连接，我在服务器上的客户端列表就会堆积起来。第一次断开连接时，我会打印出列表中的内容，因此首先得到以下信息：

{612: <socket.socket fd=612, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('192.168.1.77', 22050), raddr=('192.168.1.77', 53531)>

第二次我连接它只是堆积起来，所以看起来像这样：

{612: <socket.socket fd=612, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('192.168.1.77', 22050), raddr=('192.168.1.77', 53531)>, 620: <socket.socket fd=620, family=AddressFamily.AF_INET, type=SocketKind.SOCK_STREAM, proto=0, laddr=('192.168.1.77', 22050), raddr=('192.168.1.77', 53532)>}

我该如何做才能使它断开连接？ 这是服务器代码：

import socket
import threading
from _thread import *
from threading import Thread

clients = {}

def message(c):
    while True:
        try:
            data = c.recv(1024).decode("utf-8")
            print("Recieved from: " + str(data))
            if not data:
                print("Client Disconnected.")
                print(clients)
                break

            # skicka meddelanden till client
            for client in clients.values():
                try:
                    if client == c:
                        continue
                    client.sendall(data.encode("utf-8"))
                except ConnectionAbortedError:
                    print("[!] Connection aborted ")
                    print(str(clients))
                except ConnectionResetError:
                    print("[!] Connection reset error ")
                    print(str(clients))
        except ConnectionResetError:
            print("[!] - An existing connection was forcibly closed by the remote host. \n")
            break

def listener():
    host = "192.168.1.77"
    port = 22050
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    s.bind((host, port))
    s.listen(5)
    print("\nServer has started.\n\n" + "Host: " + host + "\nPort: " + str(port))
    print("______________________________________________________________________\n")
    while True:
        c, addr = s.accept()
        print(str(addr) + " has connected.")
        clients[c.fileno()] = c
        threading.Thread(target=message, args=(c,)).start()


if __name__ == '__main__':
    listenerthread = Thread(target=listener())
    listenerthread.start
    #listener()

这是客户端代码：

import socket
import os
from multiprocessing import Process
from threading import Thread
import sys

print("... Awaiting connection from server ...")

host = "192.168.1.77"
port = 22050

try:
    s = socket.socket()
    s.connect((host, port))
except ConnectionRefusedError:
    print("Server is down.")
    sys.exit()
try:
    print("Connected!")

    def send():
        while True:
           message = input("-> ")
           s.send(message.encode("utf-8"))
           #recieve = s.recv(1024).decode("utf-8")
           #print("- Server: " + recieve)

    def recv():
        recieve = s.recv(1024).decode("utf-8")
        print("\n" + "Server: " + recieve)

#    while message !="quitclient":
#        s.send(message.encode("utf-8"))
#        recieve = s.recv(1024).decode("utf-8")
#        print("Recieved from server: " + recieve)
#        message = input("-> ")
#    s.close()

except ConnectionResetError:
    print("Disconnected!")
    input("Press enter to exit...")
    quit()
sendthread = Thread(target=send)
recvthread = Thread(target=recv)

sendthread.start()
recvthread.start()

该客户端代码只是我拥有的GUI客户端代码的cli版本（由于编写时间太长，所以不再编写），但是它具有相同的代码。在GUI版本上，我有一个看起来像这样的断开按钮：

def Disconnect():
    s.shutdown(socket.SHUT_RDWR)
    s.close()

我在这里做什么错了？

Answer 1

clients词典仅被添加，从未删除。像下面这样的东西应该起作用。捕获任何异常并退出以从字典中删除密钥。

def message(c):
    try:
        while True:
            data = c.recv(1024).decode("utf-8")
            print("Received from: " + str(data))
            if not data:
                print("Client Disconnected.")
                print(clients)
                break

            # skicka meddelanden till client
            for client in clients.values():
                if client == c:
                    continue
                client.sendall(data.encode("utf-8"))
    except Exception as e:
        print(e)
    clients.pop(c.fileno())
    print(clients)

顺便说一句，下面的代码由于不需要start()而不是start而从不会启动线程。侦听器启动是因为它在target=listener()中被调用，应该为target=listener：

if __name__ == '__main__':
    listenerthread = Thread(target=listener())
    listenerthread.start
    #listener()

但是不需要启动线程来调用侦听器。只需使用：

if __name__ == '__main__':
    listener()

您最终还会遇到消息问题。 TCP是一种流协议，因此您不能假设每个recv都接收到send所发送的内容。 send不保证将发送每个字节……检查返回值或使用sendall。缓慢发送的小消息可能永远不会显示问题，但发送充满多字节UTF-8编码字符的大消息，则会出现错误。解决问题的简单方法请参见this recent answer of mine。

如果客户端与服务器断开连接，如何断开连接？

1 个答案: