log_dht.py

#!/usr/bin/env python
import socket
import json
import datetime
import sys
import MySQLdb
import os

# create database sensors:
#
# create table logs(
#	 date datetime,
#	 sensor char(10),
#	 reading char(12),
#	 value decimal(5,2),
#	 ip int unsigned
# )
#
# grant all privileges on table sensors.logs to '***'@'localhost' identified by '***';
# grant select on table sensors.logs to ''@'10.0.0.%';

lastreadings = {}
error = {'humidityDHT11': 4, 'temperatureDHT11':3, 'temperatureDS18B20':10}
while True:
	try:
		sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
		sock.bind(("0.0.0.0",19252))

		while True:
			data, addr = sock.recvfrom(1024)
			res = json.loads(data)
			res['ip'] = addr
			scale = float(res['scale'])
			print ",".join([str(x) for x in datetime.datetime.now(), res['type'], float(res['temperature']) * scale, float(res['humidity']) * scale, addr[0]])
			sys.stdout.flush()
			db = MySQLdb.connect(host="localhost",
					 			user="***",
								passwd="***",
								db="sensors")
			cur = db.cursor()
			vals = {'humidity': -1, 'temperature':-1}
			store = True
			
			types = ['humidity', 'temperature']
			if res['type'] == 'DS18B20':
				types = ['temperature']
			
			for reading in types:
				value = float(res[reading]) * scale
				vals[reading] = value
				if value > 0 and not (res['type'] == 'DS18B20' and value == 85 ):			
					key = res['type'] + reading + str(addr[0])

					if key in lastreadings:
						old_value = lastreadings[key]
						error_bar = error[reading + res['type']]
						if value > old_value +error_bar or value < old_value -error_bar:
							store = False
							print "Ignoring {} because too high/low from {} [{}]".format(value,old_value,key)
							continue
					cur.execute("insert into logs values (%s, %s, %s, %s, INET_ATON(%s), %s)",
						(datetime.datetime.now(),
						 res['type'],
						 reading,value,
						 str(addr[0]),
						 int(res['success'])
						 ))

					lastreadings[key] = value
				else:
					store = False
			db.commit()
			if store:
				rrdupdate = "rrdtool update {}-{}.rrd N:{}:{}".format(addr[0], res['type'],vals['humidity'], vals['temperature'])
				#print rrdupdate
				os.system(rrdupdate)
			
	except KeyboardInterrupt:
		raise
	except:
		print >> sys.stderr,  "Error! Restarting" , sys.exc_info()
		pass