cached/weather_forecast.py

   1 #!/usr/bin/env python3
   2
   3 from dataclasses import dataclass
   4 import datetime
   5 import logging
   6 import os
   7 from typing import Any
   8 import urllib.request
   9
  10 import astral  # type: ignore
  11 from astral.sun import sun  # type: ignore
  12 from bs4 import BeautifulSoup  # type: ignore
  13 from overrides import overrides
  14 import pytz
  15
  16 import argparse_utils
  17 import config
  18 import datetime_utils
  19 import dateparse.dateparse_utils as dp
  20 import persistent
  21 import text_utils
  22 import smart_home.thermometers as temps
  23
  24
  25 logger = logging.getLogger(__name__)
  26
  27 cfg = config.add_commandline_args(
  28     f'Cached Weather Forecast ({__file__})',
  29     'Arguments controlling detailed weather rendering'
  30 )
  31 cfg.add_argument(
  32     '--weather_forecast_cachefile',
  33     type=str,
  34     default=f'{os.environ["HOME"]}/cache/.weather_forecast_cache',
  35     metavar='FILENAME',
  36     help='File in which to cache weather data'
  37 )
  38 cfg.add_argument(
  39     '--weather_forecast_stalest_acceptable',
  40     type=argparse_utils.valid_duration,
  41     default=datetime.timedelta(seconds=7200),   # 2 hours
  42     metavar='DURATION',
  43     help='Maximum acceptable age of cached data.  If zero, forces a refetch'
  44 )
  45
  46
  47 @dataclass
  48 class WeatherForecast:
  49     date: datetime.date                # The date
  50     sunrise: datetime.datetime         # Sunrise datetime
  51     sunset: datetime.datetime          # Sunset datetime
  52     description: str                   # Textual description of weather
  53
  54
  55 @persistent.persistent_autoloaded_singleton()
  56 class CachedDetailedWeatherForecast(persistent.Persistent):
  57     def __init__(self, forecasts = None):
  58         if forecasts is not None:
  59             self.forecasts = forecasts
  60             return
  61
  62         now = datetime_utils.now_pacific()
  63         self.forecasts = {}
  64
  65         # Ask the raspberry pi about the outside temperature.
  66         current_temp = temps.ThermometerRegistry().read_temperature(
  67             'house_outside', convert_to_fahrenheit=True
  68         )
  69
  70         # Get a weather forecast for Bellevue.
  71         www = urllib.request.urlopen(
  72             "https://forecast.weather.gov/MapClick.php?lat=47.652775&lon=-122.170716"
  73         )
  74         forecast_response = www.read()
  75         www.close()
  76
  77         soup = BeautifulSoup(forecast_response, "html.parser")
  78         forecast = soup.find(id='detailed-forecast-body')
  79         parser = dp.DateParser()
  80
  81         said_temp = False
  82         last_dt = now
  83         dt = now
  84         for (day, txt) in zip(
  85                 forecast.find_all('b'),
  86                 forecast.find_all(class_='col-sm-10 forecast-text')
  87         ):
  88             last_dt = dt
  89             try:
  90                 dt = parser.parse(day.get_text())
  91             except Exception:
  92                 dt = last_dt
  93             assert dt is not None
  94
  95             # Compute sunrise/sunset times on dt.
  96             city = astral.LocationInfo(
  97                 "Bellevue", "USA", "US/Pacific", 47.653, -122.171
  98             )
  99             s = sun(city.observer, date=dt, tzinfo=pytz.timezone("US/Pacific"))
 100             sunrise = s['sunrise']
 101             sunset = s['sunset']
 102
 103             if dt.date() == now.date() and not said_temp and current_temp is not None:
 104                 blurb = f'{day.get_text()}: The current outside tempterature is {current_temp}. '
 105                 blurb += txt.get_text()
 106                 said_temp = True
 107             else:
 108                 blurb = f'{day.get_text()}: {txt.get_text()}'
 109             blurb = text_utils.wrap_string(blurb, 80)
 110
 111             if dt.date() in self.forecasts:
 112                 self.forecasts[dt.date()].description += '\n' + blurb
 113             else:
 114                 self.forecasts[dt.date()] = WeatherForecast(
 115                     date = dt,
 116                     sunrise = sunrise,
 117                     sunset = sunset,
 118                     description = blurb,
 119                 )
 120
 121     @classmethod
 122     @overrides
 123     def load(cls) -> Any:
 124         if persistent.was_file_written_within_n_seconds(
 125                 config.config['weather_forecast_cachefile'],
 126                 config.config['weather_forecast_stalest_acceptable'].total_seconds(),
 127         ):
 128             import pickle
 129             with open(config.config['weather_forecast_cachefile'], 'rb') as rf:
 130                 weather_data = pickle.load(rf)
 131                 return cls(weather_data)
 132         return None
 133
 134     @overrides
 135     def save(self) -> bool:
 136         import pickle
 137         with open(config.config['weather_forecast_cachefile'], 'wb') as wf:
 138             pickle.dump(
 139                 self.forecasts,
 140                 wf,
 141                 pickle.HIGHEST_PROTOCOL,
 142             )
 143         return True