TCP_ECho_Server_example.py

#Example app - TCP Echo Server
#Make a TCP server in a process that handles multiple clients
#Echos back the data the client sent

#Imports
import logging
import multiprocessing
import socket
import time

import select

logging.basicConfig(format='%(levelname)s - %(asctime)s: %(message)s',datefmt='%H:%M:%S', level=logging.DEBUG)

#Server
def chatserver(ip, port):
    server = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
    logging.info(f'Binding to {ip}:{port}')
    server.bind((ip,port))
    server.setblocking(False)
    server.listen(100)
    logging.info(f'Listening on {ip}:{port}')

    readers = [server]

    while True:
        readable, writable, errored = select.select(readers,[],[],0.5)

        for s in readable:
            try:
                if s == server:
                    client, address = s.accept()
                    client.setblocking(False)
                    readers.append(client)
                    logging.info(f'Connection: {address}')
                else:
                    data = s.recv(1024)
                    if data:
                        logging.info(f'Echo: {data}')
                        s.send(data)
                    else:
                        logging.info(f'Remove: {s}')
                        s.close()
                        readers.remove(s)

            except Exception as ex:
                logging.warning(ex.args)
            finally:
                pass

#Main
def main():
    svr = multiprocessing.Process(target=chatserver,args=['localhost',2067],daemon=True,name='Server')

    while True:
        command = input('Enter a command (start, stop)')
        if command == 'start':
            logging.info('Starting the server')
            svr.start()
            time.sleep(10)
        if command == 'stop':
            logging.info('Stopping the server')
            svr.terminate()
            svr.join()
            svr.close()
            logging.info('Server stopped')

            break
    logging.info('Application finished')

if __name__ == "__main__":
    main()