Python多线程参数传递及Socket服务器ConnectionResetError问题排查

问题描述 #

我正在编写一个支持多客户端连接的服务器程序，为每个客户端创建独立线程，但运行时出现连接相关错误。

原服务端代码 #

from socket import*
import threading

server = socket(AF_INET,SOCK_STREAM)
server.bind(('localhost',9000))
        
def handle_client(conn,addr):
    print(addr)
    while(True):
        info = conn.recv(5000).decode()
        if(len(info)>0): 
            print(info[0])
            data = "HTTP/1.1 200 OK\n"
            data += "Content-Type: text/html; charset=utf-8\n"
            data += "\n"
            data += "<html><body>Hello World</body></html>\n\n"
            conn.sendall(data.encode())
            conn.shutdown(SHUT_WR)
    
def start():
    server.listen()
    print(f"Server is listening on {server}")
    while(True):
        conn,addr = server.accept()# 等待客户端连接，返回连接对象和客户端地址元组
        thread = threading.Thread(target=handle_client,args=(conn,addr))
        thread.start()
        
start()

错误信息 #

Server is listening on <socket.socket fd=272, family=2, type=1, proto=0, laddr=('127.0.0.1', 9000)>('127.0.0.1', 50959)
0
Exception in thread Thread-1 (handle_client):
Traceback (most recent call last):
  File "C:\Users\Arun\AppData\Local\Programs\Python\Python311\Lib\threading.py", line 1038, in _bootstrap_inner
    self.run()
  File "C:\Users\Arun\AppData\Local\Programs\Python\Python311\Lib\threading.py", line 975, in run
    self._target(*self._args, **self._kwargs)
  File "e:\Desktop\Django\Django_Basics\Django_Basics\WebSockets\WorldsSimplestServer.py", line 25, in handle_client
    info = conn.recv(5000).decode()
           ^^^^^^^^^^^^^^^
ConnectionResetError: [WinError 10054] An existing connection was forcibly closed by the remote host

解决方法及修正代码 #

通过添加循环终止条件，处理完客户端请求后结束线程循环，解决了连接被强制关闭的问题。修正后的代码如下：

from socket import*
import threading
server = socket(AF_INET,SOCK_STREAM)
server.bind(('localhost',9000))
        
def handle_client(conn,addr):
    print(addr)
    connected = True
    while(connected):
        info = conn.recv(5000).decode()
        if(len(info)>0): 
            print(info[0])
            data = "HTTP/1.1 200 OK\n"
            data += "Content-Type: text/html; charset=utf-8\n"
            data += "\n"
            data += "<html><body>Hello World</body></html>\n\n"
            conn.sendall(data.encode())
            conn.shutdown(SHUT_WR)
            connected = False
    
def start():
    server.listen()
    print(f"Server is listening on {server}")
    while(True):
        conn,addr = server.accept()# 等待客户端连接，返回连接对象和客户端地址元组
        thread = threading.Thread(target=handle_client,args=(conn,addr))# 模仿Java的写法，毕竟大家都爱Java...
        thread.start()
        
start()

非常感谢各位的帮助！

内容的提问来源于stack exchange，提问作者user18920992