GPIO-Input-Listener: A simple python script that listens for gpio input events (more specifically button clicks) and calls appropriate methods. It has a very basic bouncing mechanism.It has logging capabilities and restarts itself on any exception.Basically, It's trying to imitate a daemon.I hope it might be useful to someone.

gpio_input_listener.py

#!/usr/bin/env python
#########################################################################
# GPIO-Input-Listener: A simple python script that listens for		#
# gpio input events (more specifically button clicks) and calls		#
# appropriate methods. It has a very basic bouncing mechanism.		#
# It has logging capabilities and restarts itself on any exception. 	#
# Basically, It's trying to imitate a daemon.				#
# I hope it might be useful to someone.					#
# Copyright (c) 2017 0xelectron                              	     	#
#########################################################################
import sys
from subprocess import call, check_output, STDOUT
import time
import logging
import logging.handlers
# logger config
LOG_FILENAME = "/var/log/gpio_input_listner.log"
LOG_FORMAT = logging.Formatter('%(levelname)s | %(asctime)-15s | %(message)s')

logger = logging.getLogger(__name__)
logger.setLevel(logging.DEBUG)
handler = logging.handlers.RotatingFileHandler(
				LOG_FILENAME, maxBytes=10*1024*1024, backupCount=5)
handler.setFormatter(LOG_FORMAT)
logger.addHandler(handler)

import RPi.GPIO as GPIO

logger.info("GPIO Version: {}".format(GPIO.VERSION))
logger.info("Initializing...")

# start playlist audio pin
spa_pin = 2
# start playlist video pin
spv_pin = 3
# stop falcon plyaer pin
sfp_pin = 4

# pins setup
GPIO.setmode(GPIO.BCM)
GPIO.setup(spa_pin, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(spv_pin, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(sfp_pin, GPIO.IN, pull_up_down=GPIO.PUD_UP)

# def start_playlist(pin, value):

# 	if not fppd_status():
# 		logger.warning("fpp daemon was stoped. Restarting now!")
# 		fppd_restart()

# 	if (playlist_status() and pin != sfp_pin):
# 		logger.info(""" Got pin {0} with value {1}.
# 			Ignoring as playlist is already running.""".format(pin, value))
# 		return
# 	else:
# 		if pin == spa_pin:
# 			logger.info("""Got pin {0} with value {1}.
# 				Starting audio playlist in fpp player""".format(pin, value))
# 			call(["/opt/fpp/bin.pi/fpp", "-P", "audio"])
# 		elif pin == spv_pin:
# 			logger.info("""Got pin {0} with value {1}.
# 				Starting video playlist in fpp player""".format(pin, value))
# 			call(["/opt/fpp/bin.pi/fpp", "-P", "video"])
# 		elif pin == sfp_pin:
# 			logger.info("""Got pin {0} with value {1}.
# 				Stoping playlist in fpp player""".format(pin, value))
# 			fppd_stop()
# 		else:
# 			logger.warning("""Something is really wrong here.
# 				Got pin {0} with value {1}""".format(pin, value))
# 			return
# 	return

def playlist_start(playlist):

	if not fppd_status():
		logger.warning("fpp daemon was stoped. Restarting now!")
		fppd_restart()

	if playlist_status():
		logger.info("Ignoring input as playlist is already playling")
		return
	else:
		if playlist == "audio" or playlist == "video":
			logger.info("Starting {} playlist in fpp player".format(playlist))
			call(["/opt/fpp/bin.pi/fpp", "-P", playlist])
		else:
			logger.warning("Got wrong playlist name, Ignoring it.")
			return
	return

# playlist_status: Checks if any playlists are plyaing
# returns True if there are, else False
def playlist_status():

        # get status from fpp cli
	status = str(check_output("/opt/fpp/bin.pi/fpp -s", stderr=STDOUT, shell=True)).lower()

        # This is kind of an hack, really!
        if (len(status) > 30 and "fseq" in status and
                "playlist" in status):
            return True
        return False

# fppd_restart: Restarts fpp daemon
def fppd_restart():
	logger.info("Restarting fpp daemon.")
	call(["/opt/fpp/scripts/fppd_stop"])
	call(["/opt/fpp/scripts/fppd_start"])

# fppd_status: checks status of fpp daemon
# returns True if fppd is on else False
def fppd_status():
	status = check_output("/opt/fpp/bin.pi/fpp -s", stderr=STDOUT, shell=True)

	if ("false" in str(status)):
		logger.info("fpp daemon was stoped.")
		return False
	return True

# fppd_stop: stops the currently playling
# playlist immediately and restarts daemon
def fppd_stop():
	call(["/opt/fpp/bin.pi/fpp", "-d"])
	logger.info("playlist in fpp player stoped. Now restarting fpp daemon.")
	fppd_restart()

# def main():
# look for button presses
try:
	# logger.info("")
	# GPIO.add_event_detect(sfp_pin, GPIO.BOTH, callback=start_playlist,
	# bouncetime=300)
	# GPIO.add_interrupt_callback(spv_pin, start_playlist, threaded_callback=True,
	# debounce_timeout_ms=100)

	# GPIO.wait_for_interrupts(threaded=True)

	# old input states of three pins
	ois1 = ois2 = ois3 = True

	logger.info("All done! Waiting for input...")
	while True:
		# new input states of three pins
		nis1 = GPIO.input(sfp_pin)
		nis2 = GPIO.input(spa_pin)
		nis3 = GPIO.input(spv_pin)

		# if states have changed
		if not nis1 and ois1:
			fppd_stop()
		elif not nis2 and ois2:
			playlist_start("audio")
		elif not nis3 and ois3:
			playlist_start("video")

		# update the old states
		ois1 = nis1
		ois2 = nis2
		ois3 = nis3
		# sleep
		time.sleep(0.2)

except KeyboardInterrupt:
	logger.info("Got Keyboard Interrupt. Closing Now!")
	sys.exit(0)

except Exception as e:
	logger.error("Caught Exception:", exc_info=True)
	logger.info("Restarting the script!")
	os.execv(__file__, sys.argv)

finally:
	logger.info("Cleaning up gpio setup")
	GPIO.cleanup()
	logger.info("Cleaned up!")
	logger.info("bye!")