personal/weather-server: weather_server/types.py comparison

Create initial logger for weather server.

comparison

equal deleted inserted replaced

--1:000000000000
+:efe7a1eff167
+"""Basic data types for the weather server."""
+import datetime
+import math
+import typing as t
+import attr
+import pytz
+def c_to_f(c: float) -> float:
+return c * 9 / 5 + 32
+# Values from Sontag1990 via Wikipedia:
+# https://en.wikipedia.org/wiki/Dew_point
+_MAGNUS_B = 17.62
+_MAGNUS_C = 243.12
+@attr.s(frozen=True, slots=True)
+class Reading:
+"""A single reading from a weather thingy.
+Field order is important, as it is used in CSV files.
+"""
+# The Unix timestamp of the reading.
+sample_time = attr.ib(type=datetime.datetime)
+# The temperature, in degrees Celsius.
+temp_c = attr.ib(type=float)
+# The relative humidity, in percent.
+rh_pct = attr.ib(type=float)
+# The Unix timestamp when the reading was received.
+ingest_time = attr.ib(type=datetime.datetime)
+@property
+def temp_f(self) -> float:
+return c_to_f(self.temp_c)
+@property
+def dew_point_c(self) -> float:
+gamma = self._gamma
+return _MAGNUS_C * gamma / (_MAGNUS_B - gamma)
+@property
+def dew_point_f(self) -> float:
+return c_to_f(self.dew_point_c)
+def as_dict(self) -> t.Dict[str, t.Any]:
+return attr.asdict(self, recurse=False)
+@classmethod
+def from_now(cls, **kwargs) -> 'Reading':
+return cls(ingest_time=_utc_now(), **kwargs)
+@property
+def _gamma(self) -> float:
+return (
+math.log(self.rh_pct / 100) +
+_MAGNUS_B * self.temp_c / (_MAGNUS_C + self.temp_c))
+def _utc_now():
+return datetime.datetime.utcnow().replace(tzinfo=pytz.UTC)

Mercurial > personal > weather-server