rpi_button_debouncing.py

from time import sleep

import RPi.GPIO


class PushButton:

    def __init__(self, pin, rpi_gpio=RPi.GPIO):
        self.pin = pin
        self.rpi_gpio = rpi_gpio
        self.state = None
        self.state_changed = False
        self.rpi_gpio.setup(self.pin, self.rpi_gpio.IN)

    @property
    def was_pressed(self):
        state = not self.rpi_gpio.input(self.pin)

        if state != self.state:
            self.state = state

            if self.state_changed:
                self.state_changed = False
                return True
            else:
                self.state_changed = True

        return False


def main():
    RPi.GPIO.setmode(RPi.GPIO.BOARD)

    pin = 42
    button = PushButton(pin)

    try:
        while True:
            if button.was_pressed:
                print('You pushed the button')
            else:
                print('You did not push the button')

            # Sleep for 1s
            sleep(1)

    except KeyboardInterrupt:
        pass
    finally:
        RPi.GPIO.cleanup()


if __name__ == '__main__':
    main()