these codes are mostly taken from a yt tutorial. this code gives a console based chat server . the problem is I can't use it in two computers. I can't add more clients from computers other than my computer.
this is server
import socket
import select
HEADER_LENGTH = 10
IP = "127.0.0.1"
PORT = 1234
# Create a socket
# socket.AF_INET - address family, IPv4, some otehr possible are AF_INET6, AF_BLUETOOTH, AF_UNIX
# socket.SOCK_STREAM - TCP, conection-based, socket.SOCK_DGRAM - UDP, connectionless, datagrams, socket.SOCK_RAW - raw IP packets
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
# SO_ - socket option
# SOL_ - socket option level
# Sets REUSEADDR (as a socket option) to 1 on socket
server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
# Bind, so server informs operating system that it's going to use given IP and port
# For a server using 0.0.0.0 means to listen on all available interfaces, useful to connect locally to 127.0.0.1 and remotely to LAN interface IP
server_socket.bind((IP, PORT))
# This makes server listen to new connections
server_socket.listen()
# List of sockets for select.select()
sockets_list = [server_socket]
# List of connected clients - socket as a key, user header and name as data
clients = {}
print(f'Listening for connections on {IP}:{PORT}...')
# Handles message receiving
def receive_message(client_socket):
try:
# Receive our "header" containing message length, it's size is defined and constant
message_header = client_socket.recv(HEADER_LENGTH)
# If we received no data, client gracefully closed a connection, for example using socket.close() or socket.shutdown(socket.SHUT_RDWR)
if not len(message_header):
return False
# Convert header to int value
message_length = int(message_header.decode('utf-8').strip())
# Return an object of message header and message data
return {'header': message_header, 'data': client_socket.recv(message_length)}
except:
# If we are here, client closed connection violently, for example by pressing ctrl+c on his script
# or just lost his connection
# socket.close() also invokes socket.shutdown(socket.SHUT_RDWR) what sends information about closing the socket (shutdown read/write)
# and that's also a cause when we receive an empty message
return False
while True:
# Calls Unix select() system call or Windows select() WinSock call with three parameters:
# - rlist - sockets to be monitored for incoming data
# - wlist - sockets for data to be send to (checks if for example buffers are not full and socket is ready to send some data)
# - xlist - sockets to be monitored for exceptions (we want to monitor all sockets for errors, so we can use rlist)
# Returns lists:
# - reading - sockets we received some data on (that way we don't have to check sockets manually)
# - writing - sockets ready for data to be send thru them
# - errors - sockets with some exceptions
# This is a blocking call, code execution will "wait" here and "get" notified in case any action should be taken
read_sockets, _, exception_sockets = select.select(sockets_list, [], sockets_list)
# Iterate over notified sockets
for notified_socket in read_sockets:
# If notified socket is a server socket - new connection, accept it
if notified_socket == server_socket:
# Accept new connection
# That gives us new socket - client socket, connected to this given client only, it's unique for that client
# The other returned object is ip/port set
client_socket, client_address = server_socket.accept()
# Client should send his name right away, receive it
user = receive_message(client_socket)
# If False - client disconnected before he sent his name
if user is False:
continue
# Add accepted socket to select.select() list
sockets_list.append(client_socket)
# Also save username and username header
clients[client_socket] = user
print('Accepted new connection from {}:{}, username: {}'.format(*client_address, user['data'].decode('utf-8')))
# Else existing socket is sending a message
else:
# Receive message
message = receive_message(notified_socket)
# If False, client disconnected, cleanup
if message is False:
print('Closed connection from: {}'.format(clients[notified_socket]['data'].decode('utf-8')))
# Remove from list for socket.socket()
sockets_list.remove(notified_socket)
# Remove from our list of users
del clients[notified_socket]
continue
# Get user by notified socket, so we will know who sent the message
user = clients[notified_socket]
print(f'Received message from {user["data"].decode("utf-8")}: {message["data"].decode("utf-8")}')
# Iterate over connected clients and broadcast message
for client_socket in clients:
# But don't sent it to sender
if client_socket != notified_socket:
# Send user and message (both with their headers)
# We are reusing here message header sent by sender, and saved username header send by user when he connected
client_socket.send(user['header'] + user['data'] + message['header'] + message['data'])
# It's not really necessary to have this, but will handle some socket exceptions just in case
for notified_socket in exception_sockets:
# Remove from list for socket.socket()
sockets_list.remove(notified_socket)
# Remove from our list of users
del clients[notified_socket]
and this is client
import socket
import select
import errno
import sys
HEADER_LENTH = 10
IP = "127.0.0.1"
PORT = 1234
my_username = input("Username : ")
client_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client_socket.connect((IP, PORT))
client_socket.setblocking(False)
username = my_username.encode('utf-8')
username_header = f"{len(username):<{HEADER_LENTH}}".encode('utf-8')
client_socket.send(username_header + username)
while True:
message = input(f"{my_username} > ")
if message:
message = message.encode('utf-8')
message_header = f"{len(message) :< {HEADER_LENTH}}".encode('utf-8')
client_socket.send(message_header + message)
try:
while True:
# receive things
username_header = client_socket.recv(HEADER_LENTH)
if not len(username_header):
print("Connection closed by the server")
sys.exit()
username_length = int(username_header.decode('utf-8').strip())
username = client_socket.recv(username_length).decode('utf-8')
message_header = client_socket.recv(HEADER_LENTH)
message_length = int(message_header.decode('utf-8').strip())
message = client_socket.recv(message_length).decode('utf-8')
print(f"{username} > {message}")
except IOError as e:
if e.errno != errno.EAGAIN and e.errno != errno.EWOULDBLOCK:
print('Reading error: {}'.format(str(e)))
sys.exit()
continue
except Exception as e:
print('General error', str(e))
sys.exit()
so this is it guys pls help me . I need this for my school project. pls guys.