led-server.py

#!/usr/bin/env python3

import socketserver
import logging
from random import randint


HOST, PORT = "", 999


class ArduinoLED(object):
    LEDS_AVAILABLE = ["red", "green", "blue"]
    LED_PINS = {"red": 14, "green": 13, "blue": 12}

    @classmethod
    def get_random_led(cls):
        return str(cls.LED_PINS[cls.LEDS_AVAILABLE[randint(0, 2)]])

    @classmethod
    def get_random_delay(cls):
        return str(randint(100, 2000))

    @classmethod
    def get_random_highlow(cls):
        return str(randint(0, 1))


class ArduinoTCPServer(socketserver.ThreadingMixIn, socketserver.TCPServer):
    daemon_threads = True
    allow_reuse_address = True

    def __init__(self, server_address, RequestHandlerClass):
        socketserver.TCPServer.__init__(
                self, server_address,
                RequestHandlerClass
        )


class ArduinoTCPHandler(socketserver.BaseRequestHandler):

    def _log_client_action(self, msg):
        logging.info("[{}] {}".format(self.client_address[0], msg))


    def setup(self):
        logging.info("[{}] Connected".format(self.client_address[0]))


    def handle(self):
        # handle the connection until an explicit exit is received
        while True:

            # if the connection has been closed by the client recv will
            # contain an empty string. if this happens we close the
            # connection on our end too.
            self.data = self.request.recv(1024)
            if not self.data: return True
            self.data = self.data.strip()

            self._log_client_action("Received: {}".format(self.data))

            if self.data == b"PING":
                self._log_client_action("Sending PONG")
                self.request.sendall(b"PONG\n")

            elif self.data == b"GETLED":
                led = ArduinoLED.get_random_led()
                direction = ArduinoLED.get_random_highlow()
                delay = ArduinoLED.get_random_delay()
                led_code = "{} {} {}".format(led, direction, delay)

                self._log_client_action("Sending LED Code: {}".format(led_code))
                self.request.sendall("{}\n".format(led_code).encode())

            elif self.data == b"GOODBYE":
                return True

            else:
                self._log_client_action("{} is unrecognized".format(self.data))
                self.request.sendall(b"I don't recognize that.\n")


    def finish(self):
        self._log_client_action("Closing Connection")
        self.request.sendall(b"Bye!\n")


if __name__ == "__main__":

    # setup basic logging
    logformat = "[%(asctime)s] [%(levelname)s] %(message)s "
    datefmt = "%m/%d/%y %H:%M:%S"
    logging.basicConfig(format=logformat, level=logging.DEBUG, datefmt=datefmt)
    logging.info("Starting server on port " + str(PORT))

    # start the server and keep it running until a keyboard interrupt is
    # received, in which case cleanly shut down
    server = ArduinoTCPServer((HOST, PORT), ArduinoTCPHandler)
    try:
        server.serve_forever()
    except KeyboardInterrupt:
        server.shutdown()
        server.server_close()