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Sockets Python | chatting server multiple clients

i am trying to implement a TLS secured socket server in python, and i want multiple clients to connect to the server and talk to each other,
what i would like to do is that each client connecting can receive messages sent by other clients also,
Server code:
import socket
import threading
HEADER = 64
PORT = 5050
SERVER = socket.gethostbyname(socket.gethostname())
ADDR = (SERVER, PORT)
FORMAT = 'utf-8'
DISCONNECT_MESSAGE = "!DISCONNECT"
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.bind(ADDR)
def handle_client(conn, addr):
print(f"[NEW CONNECTION] {addr} connected.")
connected = True
while connected:
msg_length = conn.recv(HEADER).decode(FORMAT)
if msg_length:
msg_length = int(msg_length)
msg = conn.recv(msg_length).decode(FORMAT)
if msg == DISCONNECT_MESSAGE:
connected = False
print(f"[{addr}] {msg}")
conn.send("Msg received".encode(FORMAT))
conn.close()
def start():
server.listen()
print(f"[LISTENING] Server is listening on {SERVER}")
while True:
conn, addr = server.accept()
thread = threading.Thread(target=handle_client, args=(conn, addr))
thread.start()
print(f"[ACTIVE CONNECTIONS] {threading.activeCount() - 1}")
print("[STARTING] server is starting ...")
start()
Client Code:
import socket
HEADER = 64
PORT = 5050
FORMAT = 'utf-8'
DISCONNECT_MESSAGE = "!DISCONNECT"
SERVER = "192.168.1.141"
ADDR = (SERVER, PORT)
client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client.connect(ADDR)
def send(msg):
message = msg.encode(FORMAT)
msg_length = len(message)
send_length = str(msg_length).encode(FORMAT)
send_length += b' ' * (HEADER - len(send_length))
client.send(send_length)
client.send(message)
print(client.recv(2048).decode(FORMAT))
send(input('[Send a Message]: '))
send(DISCONNECT_MESSAGE)
where can i add the TLS in this?:/
if something isn't right please inform me :)
---------------------EDIT------------------------------
SERVER:
import socket
import select
HEADER_LENGTH = 10
IP = "127.0.0.1"
PORT = 1234
server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
server_socket.bind((IP, PORT))
server_socket.listen(5)
sockets_list = [server_socket]
clients = {}
def receive_message(client_socket):
try:
message_header = client_socket.recv(HEADER_LENGTH)
if not len(message_header):
return False
message_length = int(message_header.decode('utf-8').strip())
return {"header": message_header, "data": client_socket.recv(message_length)}
except:
return False
while True:
read_sockets, _, exception_sockets = select.select(
sockets_list, [], sockets_list)
for notified_socket in read_sockets:
if notified_socket == server_socket:
client_socket, client_address = server_socket.accept()
user = receive_message(client_socket)
if user is False:
continue
sockets_list.append(client_socket)
clients[client_socket] = user
print(
f"Accepted new connection from {client_address[0]}:{client_address[1]} username: {user['data'].decode('utf-8')}")
else:
message = receive_message(notified_socket)
if message is False:
print(
f"closed connection from {clients[notified_socket]['data'].decode('utf-8')}")
sockets_list.remove(notified_socket)
del clients[notified_socket]
continue
user = clients[notified_socket]
print(
f"Received message from {user['data'].decode('utf-8')}: {message['data'].decode('utf-8')}")
for client_socket in clients:
if client_socket != notified_socket:
client_socket.send(
user['header'] + user['data'] + message['header'] + message['data'])
for notified_socket in exception_sockets:
sockets_list.remove(notified_socket)
del clients[notified_socket]
CLIENT:
from http import client
import socket
import select
import errno
import sys
import threading
HEADER_LENGTH = 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_LENGTH}}".encode('utf-8')
client_socket.send(username_header + username)
def send_message():
message = input(f"{my_username} > ")
if message:
message = message.encode('utf-8')
message_header = f"{len(message):<{HEADER_LENGTH}}".encode('utf-8')
client_socket.send(message_header + message)
while True:
thread = threading.Thread(target=send_message)
thread.start()
try:
while True:
# receive things
username_header = client_socket.recv(HEADER_LENGTH)
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_LENGTH)
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', str(e))
sys.exit()
continue
except Exception as e:
print('General error', str(e))
sys.exit()
unfortunately, i cant seem to get the buffer to work right , other clients only receive other clients input when they send messages, so the output is always unordered correctly.

Things to consider while failproofing socket communciation

I have a simple client/server socket program written in python. So far I think I have managed to deal with two types of certain socket errors.
server is not alive when the client is open (Connectionrejected)
server shuts down while the client is open (Connectionreset)
I am wondering what other errors I should be accounting for. When the client sends a message and the server is closed before the send happens, the client waits until it can reconnect and sends the message however I am not sure if that covers all the cases where the message can be lost or not transmitted completely.
server.py
import socket
import threading
HEADER = 8
PORT = 5050
SERVER = "127.0.0.1" #socket.gethostbyname(socket.gethostname())
ADDR = (SERVER, PORT)
FORMAT = 'utf-8'
DISCONNECT_MESSAGE = "exit"
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
#server.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
server.bind(ADDR)
def close():
server.shutdown(socket.SHUT_RDWR)
server.close()
print ("closed")
def handle_client(conn, addr):
print(f"[NEW CONNECTION] {addr} connected.")
connected = True
while connected:
msg_length = conn.recv(HEADER).decode(FORMAT)
if msg_length:
msg_length = int(msg_length)
msg = conn.recv(msg_length).decode(FORMAT)
if msg == DISCONNECT_MESSAGE:
connected = False
print(f"[{addr}] {msg}")
conn.send("Barcode received".encode(FORMAT))
conn.shutdown(socket.SHUT_RDWR)
conn.close()
def start():
server.listen()
print(f"[LISTENING] Server is listening on {SERVER}")
while True:
conn, addr = server.accept()
thread = threading.Thread(target=handle_client, args=(conn, addr))
thread.start()
print(f"[ACTIVE CONNECTIONS] {threading.active_count() - 1}")
print("[STARTING] server is starting...")
start()
client.py
import socket
import datetime
import time
HEADER = 8
PORT = 5050
FORMAT = 'utf-8'
DISCONNECT_MESSAGE = "exit"
SERVER = "127.0.0.1"
ADDR = (SERVER, PORT)
def check_connection(ADDR):
print("Trying to connect to the server...")
connected = False
client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
while not connected:
try:
client.connect(ADDR)
except socket.error as error:
connected = False
time.sleep(0.01)
print("Can't connect.Retrying...")
#print(connected)
else:
connected = True
print("Connected to the server")
return client
def send(msg,client,ADDR):
message = msg.encode(FORMAT)
msg_length = len(message)
send_length = str(msg_length).encode(FORMAT)
send_length += b' ' * (HEADER - len(send_length))
sending = True
while sending :
try:
cl_ls[0].send(send_length)
cl_ls[0].send(message)
print(cl_ls[0].recv(2048).decode(FORMAT))
sending = False
except socket.error as error:
cl_ls[0] = check_connection(ADDR)
cl_ls[0].send(send_length)
cl_ls[0].send(message)
sending = False
print(cl_ls[0].recv(2048).decode(FORMAT))
cl_ls = ["client"]
client = check_connection(ADDR)
cl_ls[0] = client
accept_more_barcodes = True
while accept_more_barcodes:
input_value = input("Type 'exit' to close input box ")
today = datetime.datetime.now()
date_time = today.strftime("%m/%d/%Y, %H:%M:%S")
input_value += ' *** ' + date_time
if (input_value).startswith("exit"):
accept_more_barcodes = False
else:
with open("barcodes.txt", "a") as f:
f.write(input_value + "\n")
send(input_value,cl_ls[0],ADDR)

how can I send a message to all of my clients connect to my server (socket)

My code is below and I just can't seem to figure out how to send messages to my clients at once
Even when I try asking for help or anything like that they say Store each client and idk how to do that. also I did try it and look it up I did it but I want it to update instantly like discord
import socket
import threading
HEADER = 64
PORT = 5050
SERVER = socket.gethostbyname(socket.gethostname())
ADDR = (SERVER, PORT)
FORMAT = 'utf-8'
DISCONNECT_MESSAGE = "!stop"
NAME_MESSAGE = "!name"
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.bind(ADDR)
def handle_client(client, addr):
print(f'[INFO] {addr} connected.')
while True:
msg_length = client.recv(HEADER).decode(FORMAT)
if not msg_length:
msg_length = int(msg_length)
msg = client.recv(msg_length).decode(FORMAT)
if msg == DISCONNECT_MESSAGE:
print(f'[DISCONNECT] {addr} Disconnected')
break
elif msg == NAME_MESSAGE:
name_length = client.recv(HEADER).decode(FORMAT)
if name_length:
name_length = int(name_length)
name = client.recv(name_length).decode(FORMAT)
addr = name
else:
<Idk what to put here>
else:
break
def start():
server.listen()
print(f'[INFO] Server is listening on {SERVER}')
while True:
conn, addr = server.accept()
thread = threading.Thread(target=handle_client, args=(conn, addr))
thread.start()
print(f'\n[INFO] Active connections: {threading.activeCount() - 1}')
print('[INFO] Server is starting...')
start()

Python socket client doesnt receive anything, hangs by recv.from(datasize)

I have to make a simple udp echo client and server, currently my problem is that the client hangs itself up at the code "data, address = sock.recvfrom(dataSize)". Here is my client and server code (I removed some api functions, so it aint long). I tried same ports and different ports and the same goes with the ip's but i dont get any message back. I tried the original file from a friend and his version works, I have the same port and ip and the same methods on both files, but it still keeps hanging at the echoClient method receiveMSG at the first line.
echoServerUDP.py
0<0# : ^
'''
#echo off
python "%~f0" %*
pause
exit /b 0
'''
#!/usr/bin/env python
import socket
import json
host = '0.0.0.0'
sport = 11111 # own port
dataSize = 1024
ip_adresses = {}
def echo_server():
receiveSock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
receiveSock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
receiveSock.bind((host,sport))
print("Starting up echo server on %s port %s" % (host, sport))
while True:
print("Waiting to receive message")
print("Generate a Session ...")
data, address = receiveSock.recvfrom(dataSize)
data = data.decode("utf-8")
if data:
print("receive data: %s from %s" % (data,address))
json_object = json.loads(data)
operation=json_object["operation"]
if operation == "register":
register(json_object["name"],json_object["value"],json_object["sid"])
json_message={"ergebnis":"ok"}
dump = json.dumps(json_message)
sendMSG(bytes(dump,encoding="utf-8"),address)
print("er")
if operation == "unregister":
unregister(json_object["name"],json_object["sid"])
if operation == "query":
query(json_object["sid"])
if operation == "reset":
reset(json_object["sid"])
print("sent %s bytes back to %s" % (data,address))
def sendMSG(data,address):
sendSock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sendSock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
sendSock.sendto(data,address)
sendSock.close()
if __name__ == '__main__':
echo_server()
and here the echoClientUDP.py
0<0# : ^
'''
#echo off
python "%~f0" %*
pause
exit /b 0
'''
#!/usr/bin/env python
import socket
import time
import json
from random import randint
host = '127.0.0.1'
sport = 11111
dataSize = 1024
sid= randint(1,10000)
name=socket.gethostname()
own_ip = socket.gethostbyname(name)
def echo_client():
sendSock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
try:
json_message = {"operation":"register","name":name,"value":own_ip,"sid":sid}
dump = json.dumps(json_message)
print("Sending %s to %s:%s" % (dump,host,sport))
sendMSG(sendSock, dump)
data = receiveMSG(sendSock)
if data:
print("Received: %s" % data)
except Exception as err:
print("Socket error: %s" %str(err))
finally:
print("Closing connection to the server")
sendSock.close()
def sendMSG(sendSock, data):
sendSock.connect((host, sport))
sendSock.sendall(bytes(data,encoding="utf-8"))
def receiveMSG(sock):
data, address = sock.recvfrom(dataSize)
print(data)
return data
if __name__ == '__main__':
echo_client()

Please put more effort in some areas like you have not added any headers and you have gone more complicated i have also created a similar working script see and observe that script and make changes to your script
client.py :-
import socket
import sys
HEADER = 64
PORT = 65432
FORMAT = 'utf-8'
DISCONNECT_MESSAGE = "!DISCONNECT"
SERVER = socket.gethostbyname(socket.gethostname())
ADDR = (SERVER, PORT)
client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client.connect(ADDR)
def send(msg):
message = msg.encode(FORMAT)
msg_length = len(message)
send_length = str(msg_length).encode(FORMAT)
send_length += b' ' * (HEADER - len(send_length))
client.send(send_length)
client.send(message)
print(client.recv(2048).decode(FORMAT))
def chat():
while True:
try:
a = input()
if 'quit' in a:
sys.exit()
else:
send(a)
except Exception as e:
print(e)
sys.exit()
chat()
server.py :-
import socket
import threading
HEADER = 64
PORT = 65432
SERVER = socket.gethostbyname(socket.gethostname())
ADDR = (SERVER, PORT)
FORMAT = 'utf-8'
DISCONNECT_MESSAGE = "Bye"
server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.bind(ADDR)
def handle_client(conn, addr):
print(f"[NEW CONNECTION] {addr} connected.")
connected = True
while connected:
msg_length = conn.recv(HEADER).decode(FORMAT)
if msg_length:
msg_length = int(msg_length)
msg = conn.recv(msg_length).decode(FORMAT)
if msg == DISCONNECT_MESSAGE:
connected = False
print(f"[{addr}] left")
print(f"[{addr}] {msg}")
conn.send("Msg received".encode(FORMAT))
conn.close()
def start():
server.listen()
print(f"[LISTENING] Server is listening on {SERVER}")
while True:
conn, addr = server.accept()
thread = threading.Thread(target=handle_client, args=(conn, addr))
thread.start()
print(f"[ACTIVE CONNECTIONS] {threading.activeCount() - 1}")
print("[STARTING] server is starting...")
start()
and i have used threading here to make the process more fast.
First run the server.py in background and then run client.py to connect to the server.

Python: Send data to one client from database

I have a python script that receives tcp data from client and I want to send a response to a specific client (I handle more than 500). This command comes from a mysql database and I handle the clientsocket by a dictionary, but the script is down when it receives a lot of connections.
How can I store the clientsocket in mysql database, or which is the best way to handle the clientsocket?
My code is:
import thread
from socket import *
def sendCommand():
try:
for clientsocket,id_client in conn_dict.iteritems():
if id_cliente == "TEST_from_mysql_db":
clientsocket.send("ACK SEND")
break
except:
print "NO"
def handler(clientsocket, clientaddr):
print "Accepted connection from: ", clientaddr
while 1:
data = clientsocket.recv(buf)
if not data:
break
else:
conn_dict[clientsocket] = id_client
sendCommand()
clientsocket.close()
if __name__ == "__main__":
conn_dict = dict()
host = str("XXX.XXX.XXX.XXX")
port = XXX
buf = 1024
addr = (host, port)
serversocket = socket(AF_INET, SOCK_STREAM)
serversocket.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
serversocket.bind(addr)
serversocket.listen(2)
while 1:
print "Server is listening for connections\n"
clientsocket, clientaddr = serversocket.accept()
thread.start_new_thread(handler, (clientsocket, clientaddr))
serversocket.close()