shutdown script for Nakayoshi Camera

camera_shutdown.sh_.py

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

import RPi.GPIO as GPIO
import time
import syslog
import os

# use GPIO 17 as shutdown button
WatchGpioNo = 17
#LEDGpioNo = 4
SleepStepSec = 0.1

def KeepWatchForSeconds(seconds):
    GoFlag = True
    if seconds < 1:
        seconds = 1
    while seconds > 0:
        time.sleep(SleepStepSec)
        seconds -= SleepStepSec
        if (GPIO.input(WatchGpioNo) == True):
            GoFlag = False
            break
    return GoFlag

def CallShutdown():
    syslog.syslog(syslog.LOG_NOTICE, "Going shutdown by GPIO.")
    os.system("/sbin/shutdown -h now 'Poweroff by GPIO'")


if __name__ == '__main__':

    GPIO.setmode(GPIO.BCM)

    GPIO.setup(WatchGpioNo, GPIO.IN, pull_up_down=GPIO.PUD_UP)

    try:
        while True:
            syslog.syslog(syslog.LOG_INFO, "Waiting for falling edge on port %d" % WatchGpioNo)
            GPIO.wait_for_edge(WatchGpioNo, GPIO.FALLING)
            syslog.syslog(syslog.LOG_INFO, "Falling edge detected.")
            if KeepWatchForSeconds(5):
                CallShutdown()
                break
        GPIO.cleanup()           # clean up GPIO on normal exit
    except KeyboardInterrupt:
            GPIO.cleanup()       # clean up GPIO on CTRL+C exit