如何在Python中使用套接字处理多线程

Question

我目前正在处理一个问题，需要让服务器同时处理多个客户端。我有一个server.py文件和一个client.py文件。以下是server.py:中的一个片段

connections = []
addresses = []
for c in connections:
c.close()
del connections[:]
del addresses[:]  #clears anything pre-existing
while True:
try:
csock, address = s.accept() #takes in connection and stores info
s.setblocking(1) #prevents timeout
connections.append(csock)
addresses.append(address)
print(f"Connection from {address} has been established!")
except:
print("Error has occurred")

当我在终端中运行服务器，然后用客户端连接到它时。它的行为正如我所期望的那样，打印出Connection from ('192.168.1.84', 50824) has been established!。

当我打开另一个终端并运行client.py以建立额外的连接时，什么都不会发生。也就是说，直到我关闭我的第一个客户端进程，然后服务器打印出

Error occurred
Connection from ('192.168.1.84', 50826) has been established!

我可以看到这里发生了什么，但我对网络很陌生，而且我在多线程方面也不是很擅长，所以有人能告诉我发生了什么以及我能做些什么让这些进程像我预期的那样同时运行吗？

Answer 1

在s.accept()之后，您应该使用threading在分离的线程中运行代码，并且该线程应该继续与客户端连接。同时，主线程可以返回到s.accept()以等待下一个客户端。

---

具有一些额外设置的最小工作代码。

服务器：

import socket
import threading
import time
# --- functions ---
def handle_client(conn, addr):
print("[thread] starting")
# recv message
message = conn.recv(1024)
message = message.decode()
print("[thread] client:", addr, 'recv:', message)

# simulate longer work
time.sleep(5)
# send answer
message = "Bye!"
message = message.encode()
conn.send(message)
print("[thread] client:", addr, 'send:', message)

conn.close()
print("[thread] ending")

# --- main ---
host = '0.0.0.0'
port = 8080
s = socket.socket()
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)  # solution for "[Error 89] Address already in use". Use before bind()
s.bind((host, port))
s.listen(1)
all_threads = []
try:
while True:
print("Waiting for client")
conn, addr = s.accept()

print("Client:", addr)

t = threading.Thread(target=handle_client, args=(conn, addr))
t.start()

all_threads.append(t)
except KeyboardInterrupt:
print("Stopped by Ctrl+C")
finally:
if s:
s.close()
for t in all_threads:
t.join()

客户端(用于测试(

import socket
# --- main ---
host = '0.0.0.0'
port = 8080
s = socket.socket()
s.connect((host, port))
print("Connected to the server")
message = "Hello"
print('send:', message)
message = message.encode()
s.send(message)
message = s.recv(1024)
message = message.decode()
print('recv:', message)