use protocol for locations

my/location/common.py

@@ -3,18 +3,29 @@ from typing import Union, Tuple, Optional
 from dataclasses import dataclass
 
 from my.core import __NOT_HPI_MODULE__
+from my.core.compat import Protocol
 
 DateIsh = Union[datetime, date, str]
 
 LatLon = Tuple[float, float]
 
 
-# TODO: add timezone to this? can use timezonefinder in tz provider instead though
-
-# converted from namedtuple to a dataclass so datasource field can be added optionally
-# if we want, can eventually be converted back to a namedtuple when all datasources are compliant
-@dataclass
-class Location:
+class LocationProtocol(Protocol):
+    lat: float
+    lon: float
+    dt: datetime
+    accuracy: Optional[float]
+    elevation: Optional[float]
+    datasource: Optional[str] = None  # which module provided this, useful for debugging
+
+
+# TODO: add timezone to this? can use timezonefinder in tz provider instead though
+
+
+# converted from namedtuple to a dataclass so datasource field can be added optionally
+# if we want, can eventually be converted back to a namedtuple when all datasources are compliant
+@dataclass
+class Location(LocationProtocol):
     lat: float
     lon: float
     dt: datetime

my/location/fallback/common.py

@@ -3,11 +3,11 @@ from dataclasses import dataclass
 from typing import Optional
 from datetime import datetime, timedelta
 
-from ..common import Location
+from ..common import LocationProtocol, Location
 
 
 @dataclass
-class FallbackLocation:
+class FallbackLocation(LocationProtocol):
     lat: float
     lon: float
     dt: datetime