text: 
  #-*- coding: utf-8 -*-
  # Author : Jeonghoonkang, github.com/jeonghoonkang
  
  import platform
  import sys
  import os
  import time
  import traceback
  import requests
  import RPi.GPIO as GPIO
  
  from socket import gethostname
  
  hostname =  gethostname()
  SERVER_ADDR = '211.184.76.80'
  
  GPIO.setwarnings(False)
  GPIO.cleanup()
  GPIO.setmode(GPIO.BCM)
  GPIO.setup(19,GPIO.OUT)  # for LED indicating
  GPIO.setup(26, GPIO.OUT) # for LED indicating
  
  def query_last_data_point(bridge_id):
  	url = 'http://%s/api/raw_bridge_last/?bridge_id=%d' % (SERVER_ADDR, bridge_id)
  	
  	try:
  		ret = requests.get(url, timeout=10)
  		if ret.ok:
  			ctx = ret.json()
  			if ctx['code'] == 0:
  				return ctx['result']['time'], ctx['result']['value']
  	except Exception:
  		#print Exception
  		pass
  	return None
  	
  bridge_id = int(hostname[5:10])
  GPIO.output(26, True) # server connection is OK, showing through LED
  
  while True:
      try:
        ret = query_last_data_point(bridge_id)
      except:
        pass
      if ret is not None:
          t, v = ret
          if t > time.time() - 30:
              dt = time.time() - t 
              GPIO.output(19, True)
              GPIO.output(26, False)
          else:
              GPIO.output(19, True)
              GPIO.output(26, True)
      else:
          GPIO.output(19, False)
          GPIO.output(26, True)
      time.sleep(5.0)
  