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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

how to maintain connection between several clients and server in a Python Sockets program

below is a basic program that has the client enter a name, then it connects to the server and gets a response, and the server then appends the name to a list, the problem is when a second client connects to the server the first client loses connection and this happens for every client that connects. how do I solve this?
server.py :
import socket
s = socket.socket()
host = "127.0.0.1"
port = 5409
s.bind((host, port))
names = []
while True:
s.listen(5)
c, addr = s.accept() # Establish connection with client.
print 'Got connection from', addr
while True:
try:
name = c.recv(1024)
print name
except:
print ""
if name not in names:
names.append(name)
message = "Hello " + name
c.sendall(message)
print names
break
client.py :
import socket # Import socket module
s = socket.socket() # Create a socket object
host = "127.0.0.1" # Get local machine name
port = 5409 # Reserve a port for your service.
name = raw_input("What Is your Name? ")
s.connect((host, port))
while True:
try:
s.send(name)
except:
break
try:
print s.recv(1024)
except:
break

You will need to make your server able to handle concurrent connections, either with multithreading, multiprocessing, or select.
The socketserver module provides convenient basic server classes using threading or multiprocessing. The official documentation has some good examples. Here is one using the threading module for concurrency:
import socket
import threading
import socketserver
class ThreadedTCPRequestHandler(socketserver.BaseRequestHandler):
def handle(self):
data = str(self.request.recv(1024), 'ascii')
cur_thread = threading.current_thread()
response = bytes("{}: {}".format(cur_thread.name, data), 'ascii')
self.request.sendall(response)
class ThreadedTCPServer(socketserver.ThreadingMixIn, socketserver.TCPServer):
pass
def client(ip, port, message):
with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
sock.connect((ip, port))
sock.sendall(bytes(message, 'ascii'))
response = str(sock.recv(1024), 'ascii')
print("Received: {}".format(response))
if __name__ == "__main__":
# Port 0 means to select an arbitrary unused port
HOST, PORT = "localhost", 0
server = ThreadedTCPServer((HOST, PORT), ThreadedTCPRequestHandler)
ip, port = server.server_address
# Start a thread with the server -- that thread will then start one
# more thread for each request
server_thread = threading.Thread(target=server.serve_forever)
# Exit the server thread when the main thread terminates
server_thread.daemon = True
server_thread.start()
print("Server loop running in thread:", server_thread.name)
client(ip, port, "Hello World 1")
client(ip, port, "Hello World 2")
client(ip, port, "Hello World 3")
server.shutdown()
server.server_close()
If you would like to build your own server without using socketserver, you can look at the source for the socketserver module (it's simple), or there are plenty of examples online of basic TCP/UDP servers using all three concurrency methods.

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)

How to make a simple multithreaded socket server in Python that remembers clients

How do I make a simple Python echo server that remembers clients and doesn't create a new socket for each request? Must be able to support concurrent access. I want to be able to connect once and continually send and receive data using this client or similar:
import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
host = raw_input("Server hostname or ip? ")
port = input("Server port? ")
sock.connect((host,port))
while True:
data = raw_input("message: ")
sock.send(data)
print "response: ", sock.recv(1024)
I.e. with the server running on port 50000, using the above client I want to be able to do this:
me#mine:~$ client.py
Server hostname or ip? localhost
Server Port? 50000
message: testa
response: testa
message: testb
response: testb
message: testc
response: testc

You can use a thread per client to avoid the blocking client.recv() then use the main thread just for listening for new clients. When one connects, the main thread creates a new thread that just listens to the new client and ends when it doesn't talk for 60 seconds.
import socket
import threading
class ThreadedServer(object):
def __init__(self, host, port):
self.host = host
self.port = port
self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
self.sock.bind((self.host, self.port))
def listen(self):
self.sock.listen(5)
while True:
client, address = self.sock.accept()
client.settimeout(60)
threading.Thread(target = self.listenToClient,args = (client,address)).start()
def listenToClient(self, client, address):
size = 1024
while True:
try:
data = client.recv(size)
if data:
# Set the response to echo back the recieved data
response = data
client.send(response)
else:
raise error('Client disconnected')
except:
client.close()
return False
if __name__ == "__main__":
while True:
port_num = input("Port? ")
try:
port_num = int(port_num)
break
except ValueError:
pass
ThreadedServer('',port_num).listen()
Clients timeout after 60 seconds of inactivity and must reconnect. See the line client.settimeout(60) in the function ThreadedServer.listen()

Python Socket Listening

All of the below mentioned is on windows machines using python 2.7
Hello,
I am currently attempting to listen on a socket for data send by a remote program. This data is then printed to the screen and user input is requested that is then returned to remote program. In testing I have been able to have the remote program send me a menu of command line programs (cmd, ipconfig, whoami, ftp) and then my program returns with a number as a selection of the menu option.
The remote program receives my response and sends the output of the selected command. ipconfig and whoami work perfectly, but cmd and ftp only returns the output of the terminal once. (I.E. I can enter one command into the FTP program and send that too the remote program before I never hear back)
The part of my code that fails is that
if ready[0]: never becomes ready a second time after the first conversation.
I know the remote program is functioning correctly as I can use netcat to act in lieu of my code and operate the cmd terminal indefinitely.
How do I go about properly implementing a python socket listener that can account for this type of connection?
My "program" in its entirety:
import socket, sys, struct, time, select
host = ''
port = 50000
connectionSevered=0
try:
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
except socket.error:
print 'Failed to create socket'
sys.exit()
print '[+] Listening for connections on port '+str(port)+'.'
s.bind((host,port))
s.listen(5)
def recvall(the_socket,timeout=2):
global connectionSevered
data=''; # Data found by recv
total_data=[]; # Finally list of everything
s.setblocking(0) #make socket non blocking
begin=time.time() #beginning time
while 1:
ready = select.select([client], [], [], .2)
if time.time()-begin > timeout:
print 'Timeout reached'
#Leave loop, timer has reached its threshold
break
if ready[0]:
print 'In ready loop!'
try:
data = client.recv(4096) #attempt to fetch data
if data:
begin=time.time() #reset timeout timer
total_data.append(data)
data='';
except socket.error:
print '[+] Lost connection to client. Printing buffer...'
connectionSevered=1 # Let main loop know connection has errored
pass
time.sleep(1)
#join all parts to make final string
return ''.join(total_data)
client, address = s.accept()
print '[+] Client connected!'
while (connectionSevered==0): # While connection hasn't errored
print "connectionSevered="+str(connectionSevered) # DEBUG
recvall(s)
response = raw_input() #take user input
client.sendto(response) #send input
client.close(0)
Please let me know if you need more information, any help would be greatly appreciated, I am very new to this and eager to learn.

Playing around with this for a while finally got it working nice with a telnet session locally using python 2.7.
What it does is it sets up a thread that runs when the client connects listening for client stuff.
When the client sends a return ("\r\n" might have to change that if your interacting with a Linux system?) the message gets printed to the server, while this is happening if there is a raw input at the server side this will get sent to the client:
import socket
import threading
host = ''
port = 50000
connectionSevered=0
class client(threading.Thread):
def __init__(self, conn):
super(client, self).__init__()
self.conn = conn
self.data = ""
def run(self):
while True:
self.data = self.data + self.conn.recv(1024)
if self.data.endswith(u"\r\n"):
print self.data
self.data = ""
def send_msg(self,msg):
self.conn.send(msg)
def close(self):
self.conn.close()
try:
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.bind((host,port))
s.listen(5)
except socket.error:
print 'Failed to create socket'
sys.exit()
print '[+] Listening for connections on port: {0}'.format(port)
conn, address = s.accept()
c = client(conn)
c.start()
print '[+] Client connected: {0}'.format(address[0])
c.send_msg(u"\r\n")
print "connectionSevered:{0}".format(connectionSevered)
while (connectionSevered==0):
try:
response = raw_input()
c.send_msg(response + u"\r\n")
except:
c.close()
The above answer will not work for more than a single connection. I have updated it by adding another thread for taking connections. It it now possible to have more than a single user connect.
import socket
import threading
import sys
host = ''
port = 50000
class client(threading.Thread):
def __init__(self, conn):
super(client, self).__init__()
self.conn = conn
self.data = ""
def run(self):
while True:
self.data = self.data + self.conn.recv(1024)
if self.data.endswith(u"\r\n"):
print self.data
self.data = ""
def send_msg(self,msg):
self.conn.send(msg)
def close(self):
self.conn.close()
class connectionThread(threading.Thread):
def __init__(self, host, port):
super(connectionThread, self).__init__()
try:
self.s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self.s.bind((host,port))
self.s.listen(5)
except socket.error:
print 'Failed to create socket'
sys.exit()
self.clients = []
def run(self):
while True:
conn, address = self.s.accept()
c = client(conn)
c.start()
c.send_msg(u"\r\n")
self.clients.append(c)
print '[+] Client connected: {0}'.format(address[0])
def main():
get_conns = connectionThread(host, port)
get_conns.start()
while True:
try:
response = raw_input()
for c in get_conns.clients:
c.send_msg(response + u"\r\n")
except KeyboardInterrupt:
sys.exit()
if __name__ == '__main__':
main()
Clients are not able to see what other clients say, messages from the server will be sent to all clients. I will leave that as an exercise for the reader.

If you're in Python 3 by now and still wondering about sockets, here's a basic way of using them:
server.py
import time
import socket
# creating a socket object
s = socket.socket(socket.AF_INET,
socket.SOCK_STREAM)
# get local Host machine name
host = socket.gethostname() # or just use (host == '')
port = 9999
# bind to pot
s.bind((host, port))
# Que up to 5 requests
s.listen(5)
while True:
# establish connection
clientSocket, addr = s.accept()
print("got a connection from %s" % str(addr))
currentTime = time.ctime(time.time()) + "\r\n"
clientSocket.send(currentTime.encode('ascii'))
clientSocket.close()
client.py
import socket
# creates socket object
s = socket.socket(socket.AF_INET,
socket.SOCK_STREAM)
host = socket.gethostname() # or just use (host = '')
port = 9999
s.connect((host, port))
tm = s.recv(1024) # msg can only be 1024 bytes long
s.close()
print("the time we got from the server is %s" % tm.decode('ascii'))
Run server.py first, then run client.py.
This is just send and receive the currentTime.
What's new in Python 3.4 sockets?
A major difference between python 2.7 sockets and python 3.4 sockets is the sending messages. you have to .encode() (usually using 'ascii' or blank as parameters/arguments)
and then using .decode()
For example use .encode() to send, and use .decode() to receive.
Extra info: client/server socket tutorial