Async TCP server example (using standard python lib asyncore)

gps_track_server.py

#!/usr/bin/env python
''' Async TCP server to make first tests of newly received GPS trackers '''

import asyncore
import socket
import logging

class Server(asyncore.dispatcher):
    def __init__(self, address):
        asyncore.dispatcher.__init__(self)
        self.logger = logging.getLogger('Server')
        self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
        self.set_reuse_addr()
        self.bind(address)
        self.address = self.socket.getsockname()
        self.logger.debug('binding to %s', self.address)
        self.listen(5)

    def handle_accept(self):
        # Called when a client connects to our socket
        client_info = self.accept()
        if client_info is not None:
            self.logger.debug('handle_accept() -> %s', client_info[1])
            ClientHandler(client_info[0], client_info[1])
    

class ClientHandler(asyncore.dispatcher):
    def __init__(self, sock, address):
        asyncore.dispatcher.__init__(self, sock)
        self.logger = logging.getLogger('Client ' + str(address))
        self.data_to_write = []

    def writable(self):
        return bool(self.data_to_write)

    def handle_write(self):
        data = self.data_to_write.pop()
        sent = self.send(data[:1024])
        if sent < len(data):
            remaining = data[sent:]
            self.data.to_write.append(remaining)
        self.logger.debug('handle_write() -> (%d) "%s"', sent, data[:sent].rstrip())

    def handle_read(self):
        data = self.recv(1024)
        self.logger.debug('handle_read() -> (%d) "%s"', len(data), data.rstrip())
        # !!!!! EAXAMPLE - ECHO
        self.data_to_write.insert(0, data)
    
    def handle_close(self):
        self.logger.debug('handle_close()')
        self.close()

def main():
    logging.basicConfig(level=logging.DEBUG, format='%(name)s:[%(levelname)s]: %(message)s')
    HOST = '0.0.0.0'
    PORT = 1507
    s = Server((HOST,PORT))
    asyncore.loop()


if __name__ == '__main__':
     main() 

Great Code! Noticed one little mistake in line 41: "self.data.to_write" should be "self.data_to_write". Otherwise a very helpful and clear code.