Server Side

server.py

import struct
import socket
from threading import Thread
from rich import print

print('\n'*100)

# server's IP address
SERVER_HOST = "0.0.0.0"
SERVER_PORT = 5002 # port we want to use
separator_token = ": " # we will use this to separate the client name & message

# initialize list/set of all connected client's sockets
client_sockets = set()
# create a TCP socket
s = socket.socket()
# make the port as reusable port
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
# bind the socket to the address we specified
s.bind((SERVER_HOST, SERVER_PORT))
# listen for upcoming connections
s.listen(5)
print(f"[*] Listening as {SERVER_HOST}:{SERVER_PORT}")

#def listen_for_client(cs):
#    """
#    This function keep listening for a message from `cs` socket
#    Whenever a message is received, broadcast it to all other connected clients
#    """
#    while True:
#        try:
#            # keep listening for a message from `cs` socket
#            #msg = cs.recv(1024).decode()
#            buff+=(socket.recv(1024))
#            if len(buff)>=size + 4:
#             if size>0:
#                callback(buff[:size].decode('utf-8'))
#             size,=struct.unpack("!L", buff[size:size+4])
#             buff=buff[size+4:]
#             #print(size)
#        except Exception as e:
#            # client no longer connected
#            # remove it from the set
#            print(f"[!] Error: {e}")
#            client_sockets.remove(cs)
#        else:
#            # if we received a message, replace the <SEP>
#            # token with ": " for nice printing
#            msg = msg.replace(separator_token, ": ")
#        # iterate over all connected sockets
#         for client_socket in client_sockets:
#            # and send the message
#            # print(msg)
#            x=msg.encode()
#            client_socket.send(struct.pack('!L', len(x))+x)#send(msg.encode())
#
def listen_for_client(socket=s, callback=print):
 try:
    buff=b""
    size=0
    while True:
        buff+=(socket.recv(1024))
        if size == 0:
            size,=struct.unpack("!L", buff[:4])
            buff=buff[4:]
        if len(buff)>=size:
            callback(buff[:size].decode('utf-8'))
            buff=buff[size:]
            size=0
 except Exception as e:
  print(f"[!] Error: {e}")
  client_sockets.remove(cs)
 else:
            # if we received a message, replace the <SEP>
            # token with ": " for nice printing
            msg = msg.replace("<SEP>", ": ")
        # iterate over all connected sockets
            for client_socket in client_sockets:
            # and send the message
            # print(msg)
             x=msg.encode()
             client_socket.send(struct.pack('!L', len(x))+x)#send(msg.encode())

while True:
    # we keep listening for new connections all the time
    client_socket, client_address = s.accept()
    print(f"[+] {client_address} connected.")
    # add the new connected client to connected sockets
    client_sockets.add(client_socket)
    # start a new thread that listens for each client's messages
    t = Thread(target=listen_for_client, args=(client_socket,))
    # make the thread daemon so it ends whenever the main thread ends
    t.daemon = True
    # start the thread
    t.start()

# close client sockets
for cs in client_sockets:
    cs.close()
# close server socket
s.close()