Raspoberry Pi + LED strip + UDP Server

rgb_server.py

from __future__ import print_function
import datetime

# Setup UDP server
import socket
UDPSock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
listen_addr = ("", 21567)
UDPSock.bind(listen_addr)
print("Listening on port {}\n".format(listen_addr[1]))
print("Commands: `COMMAND PARAMS`")
print("Valid commands:")
print("  `RESET` resets the GPIO controls for the LED strip")
print("  `STOP` stops all PWM controllers")
print("  `SET List<CHANNEL:MAGNITUDE>` sets the led strip to the given values.")
print("      CHANNEL is {r, g, b}")
print("      MAGNITUDE is a float [0, 100]")
print("      The List should be comma delimited")
print("      For example: `r:100,g:0,b:100` would make the led strip purple")

# Setup GPIO
import RPi.GPIO as GPIO
rgbPin = {"r": 17, "g": 22, "b": 24}
rgbPwm = {}
STARTED, STOPPED = "STARTED", "STOPPED"

def setup_gpio():
    GPIO.setmode(GPIO.BCM)
    for c, p in rgbPin.iteritems():
      GPIO.setup(p, GPIO.OUT)
      rgbPwm[c] = [GPIO.PWM(p, 100), STOPPED]

def teardown_gpio():
    for _, p in rgbPin.iteritems():
        GPIO.output(p, GPIO.LOW)
    GPIO.cleanup()

try:
    setup_gpio()
    # Begin listening loop
    while True:
        data, addr = UDPSock.recvfrom(1024)
        try:
            data = data.strip()
            cmd, params = data.partition(" ")[::2]
            if cmd == "RESET":
                teardown_gpio()
                setup_gpio()
            if cmd == "STOP":
                for c in rgbPwm:
                    rgbPwm[c][0].stop()
                    rgbPwm[c][1] = STOPPED
            if cmd == "SET":
                cmds = map(lambda (c, v): (c, float(v)),
                        [p.split(":") for p in params.split(",")])
                for c, v in cmds:
                    if 0 <= v <= 100:
                        if rgbPwm[c][1] == STOPPED:
                            rgbPwm[c][0].start(v)
                        else:
                            rgbPwm[c][0].ChangeDutyCycle(v)
                        rgbPwm[c][1] = STARTED
            print("{} EXECUTE {} FROM {}".format(datetime.datetime.now().isoformat(), data, addr))
        except (ValueError, LookupError, IndexError, KeyError), e:
            print("{} INVALID {} FROM {}".format(datetime.datetime.now().isoformat(), data, addr))
            print(e)
except KeyboardInterrupt:
    pass
except:
    raise
finally:
    teardown_gpio()