Fix statistic_during_period after core restart (#119323)

homeassistant/components/recorder/statistics.py

@@ -1245,7 +1245,7 @@ def _first_statistic(
     table: type[StatisticsBase],
     metadata_id: int,
 ) -> datetime | None:
-    """Return the data of the oldest statistic row for a given metadata id."""
+    """Return the date of the oldest statistic row for a given metadata id."""
     stmt = lambda_stmt(
         lambda: select(table.start_ts)
         .filter(table.metadata_id == metadata_id)
@@ -1257,6 +1257,23 @@ def _first_statistic(
     return None
 
 
+def _last_statistic(
+    session: Session,
+    table: type[StatisticsBase],
+    metadata_id: int,
+) -> datetime | None:
+    """Return the date of the newest statistic row for a given metadata id."""
+    stmt = lambda_stmt(
+        lambda: select(table.start_ts)
+        .filter(table.metadata_id == metadata_id)
+        .order_by(table.start_ts.desc())
+        .limit(1)
+    )
+    if stats := cast(Sequence[Row], execute_stmt_lambda_element(session, stmt)):
+        return dt_util.utc_from_timestamp(stats[0].start_ts)
+    return None
+
+
 def _get_oldest_sum_statistic(
     session: Session,
     head_start_time: datetime | None,
@@ -1487,7 +1504,11 @@ def statistic_during_period(
         tail_start_time: datetime | None = None
         tail_end_time: datetime | None = None
         if end_time is None:
-            tail_start_time = now.replace(minute=0, second=0, microsecond=0)
+            tail_start_time = _last_statistic(session, Statistics, metadata_id)
+            if tail_start_time:
+                tail_start_time += Statistics.duration
+            else:
+                tail_start_time = now.replace(minute=0, second=0, microsecond=0)
         elif tail_only:
             tail_start_time = start_time
             tail_end_time = end_time

tests/components/recorder/test_websocket_api.py

@@ -7,6 +7,7 @@
 from unittest.mock import ANY, patch
 
 from freezegun import freeze_time
+from freezegun.api import FrozenDateTimeFactory
 import pytest
 
 from homeassistant.components import recorder
@@ -794,17 +795,30 @@ def next_id():
     }
 
 
-@pytest.mark.freeze_time(datetime.datetime(2022, 10, 21, 6, 31, tzinfo=datetime.UTC))
+@pytest.mark.parametrize(
+    "frozen_time",
+    [
+        # This is the normal case, all statistics runs are available
+        datetime.datetime(2022, 10, 21, 6, 31, tzinfo=datetime.UTC),
+        # Statistic only available up until 6:25, this can happen if
+        # core has been shut down for an hour
+        datetime.datetime(2022, 10, 21, 7, 31, tzinfo=datetime.UTC),
+    ],
+)
 async def test_statistic_during_period_partial_overlap(
     recorder_mock: Recorder,
     hass: HomeAssistant,
     hass_ws_client: WebSocketGenerator,
+    freezer: FrozenDateTimeFactory,
+    frozen_time: datetime,
 ) -> None:
     """Test statistic_during_period."""
+    client = await hass_ws_client()
+
+    freezer.move_to(frozen_time)
     now = dt_util.utcnow()
 
     await async_recorder_block_till_done(hass)
-    client = await hass_ws_client()
 
     zero = now
     start = zero.replace(hour=0, minute=0, second=0, microsecond=0)