smart_home/thermometers.py

   1 #!/usr/bin/env python3
   2
   3 """Code involving querying various smart home thermometers."""
   4
   5 import logging
   6 import urllib.request
   7 from typing import Optional
   8
   9 logger = logging.getLogger()
  10
  11
  12 class ThermometerRegistry(object):
  13     """A registry of thermometer hosts / names and how to talk with them."""
  14
  15     def __init__(self):
  16         self.thermometers = {
  17             'house_outside': ('10.0.0.75', 'outside_temp'),
  18             'house_inside_downstairs': ('10.0.0.75', 'inside_downstairs_temp'),
  19             'house_inside_upstairs': ('10.0.0.75', 'inside_upstairs_temp'),
  20             'house_computer_closet': ('10.0.0.75', 'computer_closet_temp'),
  21             'house_crawlspace': ('10.0.0.75', 'crawlspace_temp'),
  22             'cabin_outside': ('192.168.0.107', 'outside_temp'),
  23             'cabin_inside': ('192.168.0.107', 'inside_temp'),
  24             'cabin_crawlspace': ('192.168.0.107', 'crawlspace_temp'),
  25             'cabin_hottub': ('192.168.0.107', 'hottub_temp'),
  26         }
  27
  28     def read_temperature(self, location: str, *, convert_to_fahrenheit=False) -> Optional[float]:
  29         record = self.thermometers.get(location, None)
  30         if record is None:
  31             logger.error(
  32                 'Location %s is not known.  Valid locations are %s.',
  33                 location,
  34                 self.thermometers.keys(),
  35             )
  36             return None
  37         url = f'http://{record[0]}/~pi/{record[1]}'
  38         logger.debug('Constructed URL: %s', url)
  39         try:
  40             www = urllib.request.urlopen(url, timeout=3)
  41             temp = www.read().decode('utf-8')
  42             temp = float(temp)
  43             if convert_to_fahrenheit:
  44                 temp *= 9 / 5
  45                 temp += 32.0
  46                 temp = round(temp)
  47         except Exception as e:
  48             logger.exception(e)
  49             logger.error('Failed to read temperature at URL: %s', url)
  50             temp = None
  51         finally:
  52             if www is not None:
  53                 www.close()
  54         return temp