Simple command line GPIOClass for KODI on Raspberry Pi

#!/usr/bin/env python
# -*- coding: utf-8 -*-

__author__ = 'harryberlin'

import subprocess
import xbmc


class GPIOClass(object):

    def __init__(self, pin_number):
        self.pin_number = pin_number
        self.invert_signal = False
        self.triggering = False
        self.triggering_time = 0.2
        self.isOpen = False

    @staticmethod
    def _call(command):
        try:
            try:
                output = subprocess.check_output(command, stderr=subprocess.STDOUT)
            except subprocess.CalledProcessError as error:
                output = error.output
                return error.returncode
            else:
                return output
        finally:
            pass

    def open(self, mode='out', start_level=False, off_level=False):
        if pin_number not in [4, 5, 6, 7, 12, 13, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27]:
            raise ValueError('%s is not a valid GPIO' % pin_number)

        self.invert_signal = off_level

        if mode == 'out':
            self._call('chmod 222 /sys/class/gpio/export /sys/class/gpio/unexport')
            self._call('echo %s > /sys/class/gpio/export' % self.pin_number)

            self._call('chmod 222 /sys/class/gpio/gpio%s/direction' % self.pin_number)
            self._call('chmod 222 /sys/class/gpio/gpio%s/value' % self.pin_number)
            self._call('echo %s >/sys/class/gpio/gpio%s/direction' % ('high' if self.invert_signal
                                                                      else 'low', self.pin_number))
            if start_level:
                self.set()
            else:
                self.reset()
        elif mode == 'in':
            self._call('chmod 222 /sys/class/gpio/export /sys/class/gpio/unexport')
            self._call('echo %s > /sys/class/gpio/export' % self.pin_number)

        self.isOpen = True

    def close(self):
        if self.isOpen:
            self.reset()
            self._call('echo %s > /sys/class/gpio/unexport' % self.pin_number)
            self.isOpen = False

    def set(self):
        if self.isOpen:
            if self.invert_signal:
                call('echo "0" > /sys/class/gpio/gpio%s/value' % self.pin_number)
                log('Set GPIO%s Low' % self.pin_number, 2)
            else:
                call('echo "1" > /sys/class/gpio/gpio%s/value' % self.pin_number)
                log('Set GPIO%s High' % self.pin_number, 2)

    def reset(self):
        if self.isOpen:

            if self.invert_signal:
                self._call('echo "1" > /sys/class/gpio/gpio%s/value' % self.pin_number)
                log('Reset GPIO%s High' % self.pin_number, 2)
            else:
                self._call('echo "0" > /sys/class/gpio/gpio%s/value' % self.pin_number)
                log('Reset GPIO%s Low' % self.pin_number, 2)

    def toggle(self):
        if self.isOpen:
            pin_level = bool(call('cat /sys/class/gpio/gpio%s/value' % self.pin_number))
            if pin_level:
                self.reset()
            else:
                self.set()

    def trigger(self, holdtime=0.2):
        self.triggering_time = holdtime
        if self.triggering:
            return
        thread = Thread(target=self._trigger, args=(holdtime,))
        thread.daemon = True
        self.triggering = True
        thread.start()

    def _trigger(self, holdtime=0.2):
        if self.isOpen:
            self.set()
            while self.triggering_time > 0:
                self.triggering_time -= 0.001
                time.sleep(0.001)
            self.reset()
        self.triggering = False

    def get(self):
        if self.isOpen:
            value = call('cat /sys/class/gpio/gpio%s/value' % self.pin_number)
            if '1' in value:
                return True
            else:
                return False


def log(string):
    xbmc.log('YOUR-ADDON-ID: %s' % string, xbmc.LOGNOTICE)