È possibile utilizzare socketserver per trasmettere messaggi a tutti i client connessi. Tuttavia, l'abilità non è incorporata nel codice e dovrà essere implementata estendendo alcune delle classi già fornite. Nell'esempio seguente, questo viene implementato utilizzando le classi ThreadingTCPServer e StreamRequestHandler. Forniscono una base su cui costruire, ma richiedono ancora alcune modifiche per consentire ciò che stai cercando di realizzare. La documentazione dovrebbe aiutare a spiegare ciò che ogni funzione, classe e metodo stanno cercando di fare per portare a termine il lavoro.
Server
#! /usr/bin/env python3
import argparse
import pickle
import queue
import select
import socket
import socketserver
def main():
"""Start a chat server and serve clients forever."""
parser = argparse.ArgumentParser(description='Execute a chat server demo.')
parser.add_argument('port', type=int, help='location where server listens')
arguments = parser.parse_args()
server_address = socket.gethostbyname(socket.gethostname()), arguments.port
server = CustomServer(server_address, CustomHandler)
server.serve_forever()
class CustomServer(socketserver.ThreadingTCPServer):
"""Provide server support for the management of connected clients."""
def __init__(self, server_address, request_handler_class):
"""Initialize the server and keep a set of registered clients."""
super().__init__(server_address, request_handler_class, True)
self.clients = set()
def add_client(self, client):
"""Register a client with the internal store of clients."""
self.clients.add(client)
def broadcast(self, source, data):
"""Resend data to all clients except for the data's source."""
for client in tuple(self.clients):
if client is not source:
client.schedule((source.name, data))
def remove_client(self, client):
"""Take a client off the register to disable broadcasts to it."""
self.clients.remove(client)
class CustomHandler(socketserver.StreamRequestHandler):
"""Allow forwarding of data to all other registered clients."""
def __init__(self, request, client_address, server):
"""Initialize the handler with a store for future date streams."""
self.buffer = queue.Queue()
super().__init__(request, client_address, server)
def setup(self):
"""Register self with the clients the server has available."""
super().setup()
self.server.add_client(self)
def handle(self):
"""Run a continuous message pump to broadcast all client data."""
try:
while True:
self.empty_buffers()
except (ConnectionResetError, EOFError):
pass
def empty_buffers(self):
"""Transfer data to other clients and write out all waiting data."""
if self.readable:
self.server.broadcast(self, pickle.load(self.rfile))
while not self.buffer.empty():
pickle.dump(self.buffer.get_nowait(), self.wfile)
@property
def readable(self):
"""Check if the client's connection can be read without blocking."""
return self.connection in select.select(
(self.connection,),(),(), 0.1)[0]
@property
def name(self):
"""Get the client's address to which the server is connected."""
return self.connection.getpeername()
def schedule(self, data):
"""Arrange for a data packet to be transmitted to the client."""
self.buffer.put_nowait(data)
def finish(self):
"""Remove the client's registration from the server before closing."""
self.server.remove_client(self)
super().finish()
if __name__ == '__main__':
main()
Naturalmente, è necessario anche un client in grado di comunicare con il server e utilizzare lo stesso protocollo del server parla. Poiché questo è Python, è stata presa la decisione di utilizzare il modulo pickle per facilitare il trasferimento dei dati tra server e client. Altri metodi di trasferimento dei dati potrebbero essere stati utilizzati (come JSON, XML, eccetera), ma essere in grado di mettere sottosopra e desumere i dati soddisfa abbastanza bene le esigenze di questo programma. La documentazione è inclusa di nuovo, quindi non dovrebbe essere troppo difficile capire cosa sta succedendo. Si noti che i comandi del server possono interrompere l'immissione dei dati dell'utente.
client
#! /usr/bin/env python3
import argparse
import cmd
import pickle
import socket
import threading
def main():
"""Connect a chat client to a server and process incoming commands."""
parser = argparse.ArgumentParser(description='Execute a chat client demo.')
parser.add_argument('host', type=str, help='name of server on the network')
parser.add_argument('port', type=int, help='location where server listens')
arguments = parser.parse_args()
client = User(socket.create_connection((arguments.host, arguments.port)))
client.start()
class User(cmd.Cmd, threading.Thread):
"""Provide a command interface for internal and external instructions."""
prompt = '>>> '
def __init__(self, connection):
"""Initialize the user interface for communicating with the server."""
cmd.Cmd.__init__(self)
threading.Thread.__init__(self)
self.connection = connection
self.reader = connection.makefile('rb', -1)
self.writer = connection.makefile('wb', 0)
self.handlers = dict(print=print, ping=self.ping)
def start(self):
"""Begin execution of processor thread and user command loop."""
super().start()
super().cmdloop()
self.cleanup()
def cleanup(self):
"""Close the connection and wait for the thread to terminate."""
self.writer.flush()
self.connection.shutdown(socket.SHUT_RDWR)
self.connection.close()
self.join()
def run(self):
"""Execute an automated message pump for client communications."""
try:
while True:
self.handle_server_command()
except (BrokenPipeError, ConnectionResetError):
pass
def handle_server_command(self):
"""Get an instruction from the server and execute it."""
source, (function, args, kwargs) = pickle.load(self.reader)
print('Host: {} Port: {}'.format(*source))
self.handlers[function](*args, **kwargs)
def preloop(self):
"""Announce to other clients that we are connecting."""
self.call('print', socket.gethostname(), 'just entered.')
def call(self, function, *args, **kwargs):
"""Arrange for a handler to be executed on all other clients."""
assert function in self.handlers, 'You must create a handler first!'
pickle.dump((function, args, kwargs), self.writer)
def do_say(self, arg):
"""Causes a message to appear to all other clients."""
self.call('print', arg)
def do_ping(self, arg):
"""Ask all clients to report their presence here."""
self.call('ping')
def ping(self):
"""Broadcast to all other clients that we are present."""
self.call('print', socket.gethostname(), 'is here.')
def do_exit(self, arg):
"""Disconnect from the server and close the client."""
return True
def postloop(self):
"""Make an announcement to other clients that we are leaving."""
self.call('print', socket.gethostname(), 'just exited.')
if __name__ == '__main__':
main()
Ho avuto un problema simile risolto qui: [server/client code] (http://stackoverflow.com/questions/41785969/python-tcp-server-accepting-connections -and-broadcasting-commands/41786133 # 41786133) –