Get ZoneInfo asynchronously using aiozoneinfo (#214)

Home Assistant is getting more picky about blocking operations done in the
event loop, so we need to make sure that reading timezone information from disk
is done asynchronously here.

pyproject.toml

@@ -27,6 +27,7 @@ example = "examples.energy:start"
 
 [tool.poetry.dependencies]
 aiohttp = ">=3.0.0"
+aiozoneinfo = "^0.2.0"
 async-timeout = "^4.0.3"
 python = "^3.10"
 yarl = ">=1.6.0"

spothinta_api/const.py

@@ -1,11 +1,10 @@
 """Constants for SpotHinta API client."""
+
 from __future__ import annotations
 
 from enum import Enum, unique
 from typing import Final
 
-from zoneinfo import ZoneInfo
-
 API_HOST: Final = "api.spot-hinta.fi"
 
 
@@ -30,20 +29,20 @@ class Region(Enum):
     SE4 = 14
 
 
-REGION_TO_TIMEZONE: dict[Region, ZoneInfo] = {
-    Region.DK1: ZoneInfo("Europe/Copenhagen"),
-    Region.DK2: ZoneInfo("Europe/Copenhagen"),
-    Region.FI: ZoneInfo("Europe/Helsinki"),
-    Region.EE: ZoneInfo("Europe/Tallinn"),
-    Region.LT: ZoneInfo("Europe/Vilnius"),
-    Region.LV: ZoneInfo("Europe/Riga"),
-    Region.NO1: ZoneInfo("Europe/Oslo"),
-    Region.NO2: ZoneInfo("Europe/Oslo"),
-    Region.NO3: ZoneInfo("Europe/Oslo"),
-    Region.NO4: ZoneInfo("Europe/Oslo"),
-    Region.NO5: ZoneInfo("Europe/Oslo"),
-    Region.SE1: ZoneInfo("Europe/Stockholm"),
-    Region.SE2: ZoneInfo("Europe/Stockholm"),
-    Region.SE3: ZoneInfo("Europe/Stockholm"),
-    Region.SE4: ZoneInfo("Europe/Stockholm"),
+REGION_TO_TIMEZONE: dict[Region, str] = {
+    Region.DK1: "Europe/Copenhagen",
+    Region.DK2: "Europe/Copenhagen",
+    Region.FI: "Europe/Helsinki",
+    Region.EE: "Europe/Tallinn",
+    Region.LT: "Europe/Vilnius",
+    Region.LV: "Europe/Riga",
+    Region.NO1: "Europe/Oslo",
+    Region.NO2: "Europe/Oslo",
+    Region.NO3: "Europe/Oslo",
+    Region.NO4: "Europe/Oslo",
+    Region.NO5: "Europe/Oslo",
+    Region.SE1: "Europe/Stockholm",
+    Region.SE2: "Europe/Stockholm",
+    Region.SE3: "Europe/Stockholm",
+    Region.SE4: "Europe/Stockholm",
 }

spothinta_api/models.py

@@ -1,4 +1,5 @@
 """Data models for the spot-hinta.fi API."""
+
 from __future__ import annotations
 
 from dataclasses import dataclass

spothinta_api/spothinta.py

@@ -1,4 +1,5 @@
 """Asynchronous Python client for the spot-hinta.fi API."""
+
 from __future__ import annotations
 
 import asyncio
@@ -11,6 +12,7 @@
 from aiohttp import ClientResponseError
 from aiohttp.client import ClientError, ClientSession
 from aiohttp.hdrs import METH_GET
+from aiozoneinfo import async_get_time_zone
 from yarl import URL
 
 from .const import API_HOST, REGION_TO_TIMEZONE, Region
@@ -143,7 +145,7 @@ async def energy_prices(self, region: Region = Region.FI) -> Electricity:
             msg = "No energy prices found."
             raise SpotHintaNoDataError(msg)
 
-        time_zone = REGION_TO_TIMEZONE[region]
+        time_zone = await async_get_time_zone(REGION_TO_TIMEZONE[region])
         return Electricity.from_dict(data, time_zone=time_zone)
 
     async def close(self) -> None:

tests/test_regions.py

@@ -1,10 +1,9 @@
 """Tests for regions."""
-from zoneinfo import ZoneInfo
 
 from spothinta_api.const import REGION_TO_TIMEZONE, Region
 
 
 async def test_each_region_has_a_time_zone() -> None:
     """Tests that each region has a time zone set."""
     for region in Region:
-        assert isinstance(REGION_TO_TIMEZONE[region], ZoneInfo)
+        assert isinstance(REGION_TO_TIMEZONE[region], str)