Expose statistics selector, use for recorder.get_statistics (home-assistant#147056)

* Expose statistics selector, use for `recorder.get_statistics`

* code review

* syntax formatting

* rerun ci

Author: karwosts

homeassistant/components/recorder/services.yaml

@@ -69,7 +69,7 @@ get_statistics:
         - sensor.energy_consumption
         - sensor.temperature
       selector:
-        entity:
+        statistic:
           multiple: true
 
     period:

homeassistant/helpers/selector.py

@@ -1216,6 +1216,39 @@ def __call__(self, data: Any) -> Any:
         return [parent_schema(vol.Schema(str)(val)) for val in data]
 
 
+class StatisticSelectorConfig(BaseSelectorConfig, total=False):
+    """Class to represent a statistic selector config."""
+
+    multiple: bool
+
+
+@SELECTORS.register("statistic")
+class StatisticSelector(Selector[StatisticSelectorConfig]):
+    """Selector of a single or list of statistics."""
+
+    selector_type = "statistic"
+
+    CONFIG_SCHEMA = BASE_SELECTOR_CONFIG_SCHEMA.extend(
+        {
+            vol.Optional("multiple", default=False): cv.boolean,
+        }
+    )
+
+    def __init__(self, config: StatisticSelectorConfig | None = None) -> None:
+        """Instantiate a selector."""
+        super().__init__(config)
+
+    def __call__(self, data: Any) -> str | list[str]:
+        """Validate the passed selection."""
+
+        if not self.config["multiple"]:
+            stat: str = vol.Schema(str)(data)
+            return stat
+        if not isinstance(data, list):
+            raise vol.Invalid("Value should be a list")
+        return [vol.Schema(str)(val) for val in data]
+
+
 class TargetSelectorConfig(BaseSelectorConfig, total=False):
     """Class to represent a target selector config."""
 

tests/helpers/test_selector.py

@@ -1262,3 +1262,30 @@ def test_label_selector_schema(schema, valid_selections, invalid_selections) ->
 def test_floor_selector_schema(schema, valid_selections, invalid_selections) -> None:
     """Test floor selector."""
     _test_selector("floor", schema, valid_selections, invalid_selections)
+
+
+@pytest.mark.parametrize(
+    ("schema", "valid_selections", "invalid_selections"),
+    [
+        (
+            {},
+            ("sensor.temperature",),
+            (None, ["sensor.temperature"]),
+        ),
+        (
+            {"multiple": True},
+            (["sensor.temperature", "sensor:external_temperature"], []),
+            ("sensor.temperature",),
+        ),
+        (
+            {"multiple": False},
+            ("sensor.temperature",),
+            (None, ["sensor.temperature"]),
+        ),
+    ],
+)
+def test_statistic_selector_schema(
+    schema, valid_selections, invalid_selections
+) -> None:
+    """Test statistic selector."""
+    _test_selector("statistic", schema, valid_selections, invalid_selections)