comparison py/sensor_ds18b20.py @ 148:b32e5a11a4cb

few updates, seems to run
author Matt Johnston <matt@ucc.asn.au>
date Sat, 15 Dec 2012 23:49:08 +0800
parents 482d7852b511
children d686b111dab4
comparison
equal deleted inserted replaced
147:ab1e7bf77d69 148:b32e5a11a4cb
1 #!/usr/bin/env python2.7 1 #!/usr/bin/env python2.7
2 2
3 import gevent 3 import gevent
4 import gevent.threadpool
4 import config 5 import config
5 import re 6 import re
6 from utils import L,W,E,EX 7 from utils import L,W,E,EX
7 8
8 class DS18B20s(gevent.Greenlet): 9 class DS18B20s(gevent.Greenlet):
10 THERM_RE = re.compile('.* YES\n.*t=(.*)\n', re.MULTILINE) 11 THERM_RE = re.compile('.* YES\n.*t=(.*)\n', re.MULTILINE)
11 12
12 def __init__(self, server): 13 def __init__(self, server):
13 gevent.Greenlet.__init__(self) 14 gevent.Greenlet.__init__(self)
14 self.server = server 15 self.server = server
15 # XXX set up paths 16 self.readthread = gevent.threadpool.ThreadPool(1)
16 # XXX set up drain etc 17 self.master_dir = config.SENSOR_BASE_DIR
17 18
18 def _run(self): 19 def _run(self):
19 while True: 20 while True:
20 self.do() 21 self.do()
21 gevent.sleep(config.SENSOR_SLEEP) 22 gevent.sleep(config.SENSOR_SLEEP)
22 23
23 def sensor_path(self, s): 24 def read_wait(self, f):
24 return os.path.join(self.master_dir, s) 25 # handles a blocking file read with a gevent threadpool. A
26 # real python thread performs the read while other gevent
27 # greenlets keep running.
28 # the ds18b20 takes ~750ms to read, which is noticable
29 # interactively.
30 return self.readthread.apply(lambda: f.read)
25 31
26 def do_sensor_name(self, s, contents = None): 32 def do_sensor(self, s, contents = None):
33 """ contents can be set by the caller for testing """
27 try: 34 try:
28 if contents is None: 35 if contents is None:
29 fn = os.path.join(self.sensor_path(s), 'w1_slave') 36 fn = os.path.join(self.master_dir, s, 'w1_slave')
30 f = open(fn, 'r') 37 f = open(fn, 'r')
31 contents = f.read() 38 contents = self.read_wait(f)
32 match = self.THERM_RE.match(contents) 39 match = self.THERM_RE.match(contents)
33 if match is None: 40 if match is None:
34 return None 41 return None
35 temp = int(match.groups(1)[0]) 42 temp = int(match.groups(1)[0])
36 return temp / 1000.0 43 return temp / 1000.0
47 54
48 self.server.add_reading(vals) 55 self.server.add_reading(vals)
49 56
50 def sensor_names(self): 57 def sensor_names(self):
51 """ Returns a sequence of sensorname """ 58 """ Returns a sequence of sensorname """
52 return [d for d in os.listdir(self.master_dir) if 59 slaves_path = os.path.join(self.master_dir, "w1_master_slaves")
53 os.stat(sensor_path(d)).st_mode & stat.S_ISDIR] 60 return open(slaves_path, 'r').split()
54 61
55 def wort_name(self): 62 def wort_name(self):
56 return config.WORT_NAME 63 return config.WORT_NAME
57 64
58 def fridge_name(self): 65 def fridge_name(self):