I am working on this simple chat program with a student studying Python.
https://www.geeksforgeeks.org/simple-chat-room-using-python/
I set up the server on my macbook, with
python server.py 0.0.0.0 6677
where server.py is the script:
# Python program to implement server side of chat room.
import socket
import select
import sys
from thread import *
"""The first argument AF_INET is the address domain of the
socket. This is used when we have an Internet Domain with
any two hosts The second argument is the type of socket.
SOCK_STREAM means that data or characters are read in
a continuous flow."""
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
# checks whether sufficient arguments have been provided
if len(sys.argv) != 3:
print ("Correct usage: script, IP address, port number")
exit()
# takes the first argument from command prompt as IP address
IP_address = str(sys.argv[1])
# takes second argument from command prompt as port number
Port = int(sys.argv[2])
"""
binds the server to an entered IP address and at the
specified port number.
The client must be aware of these parameters
"""
server.bind((IP_address, Port))
"""
listens for 100 active connections. This number can be
increased as per convenience.
"""
server.listen(100)
list_of_clients = []
def clientthread(conn, addr):
# sends a message to the client whose user object is conn
conn.send("Welcome to this chatroom!")
while True:
try:
message = conn.recv(2048)
if message:
"""prints the message and address of the
user who just sent the message on the server
terminal"""
print ("<" + addr[0] + "> " + message)
# Calls broadcast function to send message to all
message_to_send = "<" + addr[0] + "> " + message
broadcast(message_to_send, conn)
else:
"""message may have no content if the connection
is broken, in this case we remove the connection"""
remove(conn)
except:
continue
"""Using the below function, we broadcast the message to all
clients who's object is not the same as the one sending
the message """
def broadcast(message, connection):
for clients in list_of_clients:
if clients!=connection:
try:
clients.send(message)
except:
clients.close()
# if the link is broken, we remove the client
remove(clients)
"""The following function simply removes the object
from the list that was created at the beginning of
the program"""
def remove(connection):
if connection in list_of_clients:
list_of_clients.remove(connection)
while True:
"""Accepts a connection request and stores two parameters,
conn which is a socket object for that user, and addr
which contains the IP address of the client that just
connected"""
conn, addr = server.accept()
"""Maintains a list of clients for ease of broadcasting
a message to all available people in the chatroom"""
list_of_clients.append(conn)
# prints the address of the user that just connected
print (addr[0] + " connected")
# creates and individual thread for every user
# that connects
start_new_thread(clientthread,(conn,addr))
conn.close()
server.close()
Then, on the same macbook, to add a user,
python client.py 0.0.0.0 6677
where client.py is the script
# Python program to implement client side of chat room.
import socket
import select
import sys
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
if len(sys.argv) != 3:
print ("Correct usage: script, IP address, port number")
exit()
IP_address = str(sys.argv[1])
Port = int(sys.argv[2])
server.connect((IP_address, Port))
while True:
# maintains a list of possible input streams
sockets_list = [sys.stdin, server]
""" There are two possible input situations. Either the
user wants to give manual input to send to other people,
or the server is sending a message to be printed on the
screen. Select returns from sockets_list, the stream that
is reader for input. So for example, if the server wants
to send a message, then the if condition will hold true
below.If the user wants to send a message, the else
condition will evaluate as true"""
read_sockets,write_socket, error_socket = select.select(sockets_list,[],[])
for socks in read_sockets:
if socks == server:
message = socks.recv(2048)
print (message)
else:
message = sys.stdin.readline()
server.send(message)
sys.stdout.write("<You>")
sys.stdout.write(message)
sys.stdout.flush()
server.close()
and then, on a Windows 10 computer, I run
python client.py 192.168.0.41 6677 (my server's broadcast address, read off ifconfig)
The client then connects successfully to the server, as can be seen on the server. But, the Windows computer does not join the chat, rather reading the error "[WinError 10038] an operation was attempted on something that is not a socket".
I was able to get it to work on macbook to linux. Is this something to do with a Windows firewall?
