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Cannot run multiple files when connected to Server in VSCode Python

I am trying to test connections to a server from a network. I have 2 seperate files; server.py and network.py.
My server.py works as it says "Server Started" but when I try to run network.py to connect to the server, it does not let me run it. I am doing this in VSCode so I don't know if its a software bug.
I have provided the server.py code and network.py code (They are in the same workspace and directory) and for privacy I have hidden my IP address
Server.py:
import socket
from _thread import *
import sys
server = "XXXXXX" # server address on LAN
port = 5555 # 5555 is an open safe port for use
socket_x = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
# .AF_INET allows sokcet to communicate with addresses
# SOCK_STREAM IS USED BY TCP SERVER WHICH ALLOWS DEVICES TO TRANSMIT DATA TO ONE ANOTHER
try: # check for socket errors
socket_x.bind((server, port)) # creating server
except socket.error as e:
str(e)
socket_x.listen(2) # allows for connections (2 people can connect)
print("Waiting for Connection, Test Server Started")
def threaded_client(conn):
conn.send(str.encode("Connected"))
reply = ""
while True:
try:
data = conn.recv(2048)
reply = data.decode("utf-8")
if not data:
print("Disconnected")
break
else: # if there is data
print("Recieved: ", reply)
print("Sending: ", reply)
conn.sendall(str.encode(reply))
except:
break
print("Lost connection")
conn.close()
while True: # continuosly looking for connections
conn, address = socket_x.accept() # accept any incoming connections and store into variables
print("Connected to:", address)
# start_new_thread(threaded_client, (conn, ))
start_new_thread(threaded_client, (conn, ))
Network.py:
import socket
class Network:
def __init__(self):
self.client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.server = "XXXXXX" # will always be the same
self.port = 5555
self.address = (self.server, self.port)
self.id = self.connect()
print(self.id)
def connect(self):
try: # trying to connect
self.client.connect(self.address)
return self.client.recv(2048).decode()
except:
pass
n = Network()
Thank you for the help

Send and receive messages on same port? Peer to peer message app python

I'm trying to create a peer to peer message app, I understand I need each instance of the app to be both a server and a client as I've got for the below code but I'm wondering how to set up the ports, can I send and receive messages on the same port?
The below code is one instance of the app, I can communicate with another version but I have to set the other version to send messages on port 9000 and receive messages on 6190. This won't work going forward as how would a third user connect?
Current situation:
User 1: Receives on 9000, sends on 6190
User 2: Receives on 6190, sends on 9000
import socket
import time
import threading
global incoming
def server_socket(): #call server_socket() in build method?
try:
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind(('', 9000))
s.listen(1)
host_name = socket.gethostname()
ip_address = socket.gethostbyname(host_name)
print("IP address is: ", ip_address)
except socket.error as e:
print("Socket Error !!", "Unable To Setup Local Socket. Port In Use")
while True:
conn, addr = s.accept()
incoming_ip = str(addr[0])
data = conn.recv(4096)
data = data.decode('utf-8')
print("message recieved is: ", data)
conn.close()
s.close()
def client_send_message():
message = "Hello World"
message = message.encode('utf-8')
c = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
c.connect(("127.0.0.1", 6190))
except Exception as e:
print("Connection Refused", "The Address You Are Trying To Reach Is Currently Unavailable")
try:
c.send(message)
except Exception as e:
print(e)
c.close()
t = threading.Thread(target=server_socket)
t.start()
for i in range(5):
time.sleep(30)
client_send_message()

You currently use TCP and with this design you need a separat socket for each client. You can exchange data on this socket in both directions though. More common for peer to peer networks is UDP: here you can use a single socket to recvfrom data from arbitrary clients and sendto data to arbitrary clients.

Problems in receiving data as a client in Python (TCP)

I have a little problem in my client chat app, basically the app crash if I try to do a function that receive data separately from the one that I use to send them.
Basically, if I have only this function it works:
def send_message (ip_address, port, message):
#Connect to the server
c = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
c.connect((ip_address, port))
#Convert message in bytes-like object
message = message.encode("utf8")
c.send(message)
#Receive data
data = c.recv(88888888888888)
#Decode data from bytes-like object
data = data.decode("utf8")
return data
If I try to do two function, it doesn't work, like this:
def send_message (ip_address, port, message):
#Connect to the server
c = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
c.connect((ip_address, port))
#Convert message in bytes-like object
message = message.encode("utf8")
c.send(message)
def receive_message (ip_address, port, message):
#Connect to the server
c = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
c.connect((ip_address, port))
#Receive data
data = c.recv(88888888888888)
#Decode data from bytes-like object
data = data.decode("utf8")
return data
When I try to call the receive_message function from my GUI the app stop working. Hoping someone can help
EDIT: This is the server code:
import socket
import sys
from threading import Thread
def client_thread(conn, ip, port, MAX_BUFFER_SIZE = 4096):
# the input is in bytes, so decode it
input_from_client_bytes = conn.recv(MAX_BUFFER_SIZE)
# decode input and strip the end of line
input_from_client = input_from_client_bytes.decode("utf8").rstrip()
print("Result of processing is: {}".format(input_from_client))
vysl = res.encode("utf8") # encode the result string
conn.sendall(vysl) # send it to client
conn.close() # close connection
print('Connection ' + ip + ':' + port + " ended")
def start_server():
import socket
soc = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
# this is for easy starting/killing the app
soc.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
print('Socket created')
try:
soc.bind(("127.0.0.1", 12345))
print('Socket bind complete')
except socket.error as msg:
import sys
print('Bind failed. Error : ' + str(sys.exc_info()))
sys.exit()
#Start listening on socket
soc.listen(10)
print('Socket now listening')
# for handling task in separate jobs we need threading
from threading import Thread
# this will make an infinite loop needed for
# not reseting server for every client
while True:
conn, addr = soc.accept()
ip, port = str(addr[0]), str(addr[1])
print('Accepting connection from ' + ip + ':' + port)
try:
Thread(target=client_thread, args=(conn, ip, port)).start()
except:
print("Terible error!")
import traceback
traceback.print_exc()
soc.close()
start_server()

You don't show what's on the other end of your connection. I guess it's something like an echo which responds to received messages.
In the first case you open a single connection, first write to it, then read a response.
In the second case you open two separate connections. You write to the first one socket, read from the second one. Is anyone writing on the second socket? I guess not.

create multi-thread tcp server python 3

Hello I tried to make a simple server that accept multiple clients simultaneously I'm new to python and I have a difficult to understand it....I try to change my code in multi-thread applications but without positive result...here is the code:
import socket, threading
def message():
while 1:
data = connection.recv(1024)
if not data: break
#connection.sendall(b'-- Message Received --\n')
print(data.decode('utf-8'))
connection.close()
def connection():
address = input("Insert server ip")
port = 44444
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((address, port))
s.listen(1)
print("Server started! Waiting for connections...")
def accept connection():
connection, address = s.accept()
print('Client connected with address:', address)
t=thread.Threading(target=message,args=(connection))
t.run()
I know that there are many errors but I'm new in python sorry :(
The original non-threaded code is:
import socket
address = input("Insert server ip:")
port = 44444
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((address, port))
s.listen(1)
print("Server started! Waiting for connections...")
connection, address = s.accept()
print('Client connected with address:', address)
while 1:
data = connection.recv(1024)
if not data: break
#connection.sendall(b'-- Message Received --\n')
print(data.decode('utf-8'))
connection.close()

Your basic design is close, but you've got a whole lot of little problems making it hard to move forward.
First, you have a function name with a space in it, which isn't allowed. And you have an IndentationError because you didn't indent its contents.
Next, inside that accept_connection function, you're using threading wrong.
thread.Threading doesn't exist; you probably meant threading.Thread.
args has to be a sequence (tuple, list, etc.) of values. You probably expected (connection) to be a tuple of one value, but it's not; tuples are defined by commas, not parentheses, and what you have is just the value connection with superfluous parentheses around it. You wanted (connection,) here.
Also, calling run on a thread object just runs the thread's code in the current thread. You want to call start, which will start a new thread and call the run method on that thread.
Meanwhile, you're never actually calling this function anywhere, so of course it can't do anything. Think about where you want to call it. After creating the listener socket, you want to loop around accept, kicking off a new client thread for each accepted connection, right? So, you want to call it in a loop, either inside connection, or at the top level (in which case connection has to return s).
And finally, your accept_connection function can't access local variables from some other function; if you want it to use a socket named s, you have to pass it as a parameter.
So:
def connection():
address = input("Insert server ip")
port = 44444
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((address, port))
s.listen(1)
print("Server started! Waiting for connections...")
while True:
accept_connection(s)
def accept_connection(s):
connection, address = s.accept()
print('Client connected with address:', address)
t=thread.Threading(target=message, args=(connection,))
t.start()
As a side note, be careful with using sock.recv(1024) and assuming you're going to get the whole message that the other side sent with send(msg). You might get that, or you might get half the message, or the whole message plus half of another message the client sent later. Sockets are just streams of bytes, like files, not streams of separate messages; you need some kind of protocol to separate messages.
The simplest possible protocol is to send each message on its own line. Then you can just do socket.makefile() and for line in f:, just like you would for a real file. Of course this doesn't work if your messages can have newlines, but you can, e.g., backslash-escape them on one side and unescape them on the other.

This is a pretty old post but there's a nice way to do what you're talking about. Here's a link to an example I posted a little while back:
https://bitbucket.org/matthewwachter/tcp_threadedserver/src/master/
And the script:
from datetime import datetime
from json import loads, dumps
from pprint import pprint
import socket
from threading import Thread
class ThreadedServer(Thread):
def __init__(self, host, port, timeout=60, debug=False):
self.host = host
self.port = port
self.timeout = timeout
self.debug = debug
Thread.__init__(self)
# run by the Thread object
def run(self):
if self.debug:
print(datetime.now())
print('SERVER Starting...', '\n')
self.listen()
def listen(self):
# create an instance of socket
self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
# bind the socket to its host and port
self.sock.bind((self.host, self.port))
if self.debug:
print(datetime.now())
print('SERVER Socket Bound', self.host, self.port, '\n')
# start listening for a client
self.sock.listen(5)
if self.debug:
print(datetime.now())
print('SERVER Listening...', '\n')
while True:
# get the client object and address
client, address = self.sock.accept()
# set a timeout
client.settimeout(self.timeout)
if self.debug:
print(datetime.now())
print('CLIENT Connected:', client, '\n')
# start a thread to listen to the client
Thread(target = self.listenToClient,args = (client,address)).start()
# send the client a connection message
# res = {
# 'cmd': 'connected',
# }
# response = dumps(res)
# client.send(response.encode('utf-8'))
def listenToClient(self, client, address):
# set a buffer size ( could be 2048 or 4096 / power of 2 )
size = 1024
while True:
try:
# try to receive data from the client
data = client.recv(size).decode('utf-8')
if data:
data = loads(data.rstrip('\0'))
if self.debug:
print(datetime.now())
print('CLIENT Data Received', client)
print('Data:')
pprint(data, width=1)
print('\n')
#send a response back to the client
res = {
'cmd': data['cmd'],
'data': data['data']
}
response = dumps(res)
client.send(response.encode('utf-8'))
else:
raise error('Client disconnected')
except:
if self.debug:
print(datetime.now())
print('CLIENT Disconnected:', client, '\n')
client.close()
return False
if __name__ == "__main__":
ThreadedServer('127.0.0.1', 8008, timeout=86400, debug=True).start()

Here is some example code I have showing a threaded socket connection.
def sock_connection( sock, host ):
"Handle socket"
pass
while 1:
try:
newsock = sock.accept()
thread = Thread( target=sock_connection, args=newsock )
thread.start()
except Exception, e:
print "error on socket connection: " % e)

Python server programming

I am trying a little client server project to get me into network programming but I seem to have got stuck at the first hurdle. I cant seem to get past getting the first line of data only even if its a new connection.
#!/usr/bin/python
import socket
s = socket.socket()
host = '192.168.0.233' # Test Server
port = 7777
s.bind((host, port))
s.listen(5)
while True:
c, addr = s.accept()
print 'Got connection from', addr
data = c.recv(2048)
print(data)
If I telnet to the host running the server, the connection opens fine and I see on the server Got connection from addr, but I also only see the first line of data when I sent 4 lines of data,
I thought because its in a loop it should now always be looking for data?
I know im doing something wrong but unsure what.
Im using Python 2.6.6

recv needs to be in a loop too, at the moment your code is receiving some data and then waiting for a new connection.
https://docs.python.org/2/library/socket.html#example has an example of socket.recv in a loop.

Try this:
#!/usr/bin/python
import socket
import threading
def listenForClients(sock):
while True:
client, address = sock.accept()
client.settimeout(5)
threading.Thread( target = listenToClient, args = (client,address) ).start()
def listenToClient(client, address):
size = 2048
while True:
try:
data = client.recv(size)
if data:
response = "Got connection"
client.send(response)
else:
raise error('Client disconnected')
except:
client.close()
return False
def main(host, port):
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
sock.bind((host, port))
sock.listen(5)
listenForClients(sock)
if __name__ == "__main__":
main('192.168.0.233',7777)
Here I use a thread for each client. The problem that you have with having Socket.accept() in the loop is that it blocks meaning that concurrent access won't work and you'll only be able to talk to one client at a time.
Try running it in the background and sending it messages with:
#!/usr/bin/python
import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect(('192.168.0.233',7777))
vwhile True:
data = raw_input("enter a message: ")
sock.send(data)
print sock.recv(2048)