I started a TCP server in Python and tried to send to it multiple requests using a single socket connection:
>>> import socket
>>> s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
>>> s.connect(('127.0.0.1', 4444))
>>> message = b'hi'
>>> s.sendall(message)
>>> resp = s.recv(4096)
>>> resp
b'hello'
>>> # Now trying to send another message without restarting the socket
>>> s.sendall(message)
>>> resp = s.recv(4096)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ConnectionAbortedError: [WinError 10053] An established connection was aborted by the software in your host machine
The server rejects my second request, I'll have to close and restart the socket so I can send a new request.
This is how my server looks like:
import socketserver
class MyTCPServer(socketserver.BaseRequestHandler):
def handle(self):
message = self.request.recv(4096)
self.request.sendall(b'hello')
server = socketserver.TCPServer(('127.0.0.1', 4444), MyTCPServer)
server.serve_forever()
How can I make the server keep the connection alive and thus accept multiple requests using a single socket?
Here's a sample that shows how the same connected socket can be used for multiple send/receive sequences.
This is not meant to represent robust production-appropriate code:
from socket import socket, AF_INET, SOCK_STREAM
from socketserver import BaseRequestHandler, TCPServer
from threading import Thread
HOST = "localhost"
PORT = 10101
ADDR = HOST, PORT
RECVBUF = 4096
class MyHandler(BaseRequestHandler):
def handle(self):
while self.request.recv(RECVBUF):
self.request.sendall(b"Hello world!")
def server(tcpserver):
tcpserver.serve_forever()
def echo():
with socket(AF_INET, SOCK_STREAM) as s:
s.connect(ADDR)
for _ in range(5): # do this multiple times with the same connected socket
s.sendall(b"Some dummy data")
print(s.recv(RECVBUF).decode())
if __name__ == "__main__":
with TCPServer(ADDR, MyHandler) as tcpserver:
(t := Thread(target=server, args=[tcpserver])).start()
echo()
tcpserver.shutdown()
t.join()
Output:
Hello world!
Hello world!
Hello world!
Hello world!
Hello world!