station.py

#!/usr/bin/python
import sys
import Adafruit_DHT
import json
import time
from datetime import datetime

def update(hum, temp, t):
	with open('/var/www/html/data.json', 'r+') as f:
		data = json.load(f)
		data['hum'].append(hum);
		data['temp'].append(temp);
                data['t'].append(t);
		if len(data['hum'])>500:
			data['hum'].pop(0);
                	data['temp'].pop(0);
        	        data['t'].pop(0);
		f.seek(0);
		f.truncate();
		json.dump(data, f);
	return

hsum, tsum, c=0, 0, 0

while True:
	hum, temp = Adafruit_DHT.read_retry(22, 4)
	if hum is None or temp is None or hum > 100:
		continue
	hsum+=hum; tsum+=temp; c+=1;
	if c>9:
		update(hsum/c, tsum/c, datetime.now().strftime('%Y/%m/%d %H:%M'));
		hsum, tsum, c=0, 0, 0
	time.sleep(60)