Force timestamp to UTC

ruuvitag_sensor/decoder.py

@@ -2,7 +2,7 @@
 import logging
 import math
 import struct
-from datetime import datetime
+from datetime import datetime, timezone
 from typing import Optional, Tuple, Union
 
 from ruuvitag_sensor.ruuvi_types import ByteData, SensorData3, SensorData5, SensorDataUrl, SensorHistoryData
@@ -320,7 +320,7 @@ def _get_timestamp(self, data: list[str]) -> datetime:
         # The timestamp is a 4-byte value after the header byte, in seconds since Unix epoch
         timestamp_bytes = bytes.fromhex("".join(data[3:7]))
         timestamp = int.from_bytes(timestamp_bytes, "big")
-        return datetime.fromtimestamp(timestamp, tz=None)
+        return datetime.fromtimestamp(timestamp, tz=timezone.utc)
 
     def _get_temperature(self, data: list[str]) -> Optional[float]:
         """Return temperature in celsius"""

ruuvitag_sensor/ruuvi.py

@@ -367,7 +367,8 @@ async def get_history_async(
             max_items (Optional[int]): Maximum number of history entries to fetch. If None, gets all available data
 
         Yields:
-            SensorHistoryData: Individual history measurements with timestamp. Each entry contains one measurement type.
+            SensorHistoryData: Individual history measurements with timestamp (UTC).
+                               Each entry contains one measurement type.
 
         Raises:
             RuntimeError: If connection fails or device doesn't support history
@@ -403,7 +404,7 @@ async def download_history(
             max_items (Optional[int]): Maximum number of history entries to fetch. If None, gets all available data
 
         Returns:
-            List[SensorHistoryData]: List of historical measurements, ordered by timestamp.
+            List[SensorHistoryData]: List of historical measurements, ordered by timestamp (UTC).
                                    Each entry contains one measurement type.
 
         Raises:

tests/test_decoder.py

@@ -1,4 +1,4 @@
-from datetime import datetime
+from datetime import datetime, timezone
 from unittest import TestCase
 
 from ruuvitag_sensor.decoder import Df3Decoder, Df5Decoder, HistoryDecoder, UrlDecoder, get_decoder, parse_mac
@@ -208,7 +208,7 @@ def test_history_decode_real_samples(self):
         assert result["temperature"] == 22.75
         assert result["humidity"] is None
         assert result["pressure"] is None
-        assert result["timestamp"] == datetime(2025, 2, 1, 7, 46, 10)
+        assert result["timestamp"] == datetime(2025, 2, 1, 5, 46, 10, tzinfo=timezone.utc)
 
         # Test humidity data
         data = bytearray(b':1\x10g\x9d\xb5"\x00\x00\x10\x90')
@@ -217,7 +217,7 @@ def test_history_decode_real_samples(self):
         assert result["humidity"] == 42.4
         assert result["temperature"] is None
         assert result["pressure"] is None
-        assert result["timestamp"] == datetime(2025, 2, 1, 7, 46, 10)
+        assert result["timestamp"] == datetime(2025, 2, 1, 5, 46, 10, tzinfo=timezone.utc)
 
         # Test pressure data
         data = bytearray(b':2\x10g\x9d\xb5"\x00\x01\x8b@')
@@ -226,7 +226,7 @@ def test_history_decode_real_samples(self):
         assert result["pressure"] == 35648
         assert result["temperature"] is None
         assert result["humidity"] is None
-        assert result["timestamp"] == datetime(2025, 2, 1, 7, 46, 10)
+        assert result["timestamp"] == datetime(2025, 2, 1, 5, 46, 10, tzinfo=timezone.utc)
 
     def test_history_end_marker(self):
         decoder = HistoryDecoder()