import SocketServer
class MyTCPHandler(SocketServer.BaseRequestHandler):

    users_ids=[]
    clients = []
    
    def handle(self):
        user_id=self.request.recv(1024).strip()
        already_logged_in = False
        for i in range(len(self.users_ids)):
            if(self.users_ids[i] == user_id):
                already_logged_in = True
                break
        if not already_logged_in:
            print "client: %s connected as " % self.client_address[0] + user_id
            self.users_ids.append(user_id)
            self.clients.append(self.request)
            response = "connected"
        else:
            response = "already logged in"
        self.request.send(response)
        for i in range(len(self.clients)):
            if(self.clients[i] != self.request):
                self.clients[i].send("new user connected")
                
        
if __name__ == "__main__":
    HOST, PORT = "localhost", 9999
    server = SocketServer.TCPServer((HOST, PORT), MyTCPHandler)
    server.serve_forever()

import socket
import sys
import time
HOST, PORT = "localhost", 9999
data = " ".join(sys.argv[1:])

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.connect((HOST, PORT))
sock.send(data)

while 1:
    time.sleep(0.03)
    received = sock.recv(1024)
    if(received != ""):
        print "Received: %s" % received

while 1:
    time.sleep(0.03)
    received = sock.recv(1024)
    if(received != ""):
        print "Received: %s" % received

        already_logged_in = False
        for i in range(len(self.users_ids)):
            if(self.users_ids[i] == user_id):
                already_logged_in = True
                break

already_logged_in = user_id in self.users_ids