perf: only write state when data changes (#954)

custom_components/tesla_custom/__init__.py

@@ -427,6 +427,7 @@ def __init__(
         self.update_vehicles = update_vehicles
         self._debounce_task = None
         self._last_update_time = None
+        self.last_controller_update_time: float | None = None
         self.assumed_state = True
 
         update_interval = timedelta(seconds=MIN_SCAN_INTERVAL)
@@ -477,8 +478,11 @@ async def _async_update_data(self):
             raise UpdateFailed(f"Error communicating with API: {err}") from err
         else:
             if vin := self.vin:
+                self.last_controller_update_time = controller.get_last_update_time(
+                    vin=vin
+                )
                 self.assumed_state = not controller.is_car_online(vin=vin) and (
-                    controller.get_last_update_time(vin=vin)
+                    self.last_controller_update_time
                     - controller.get_last_wake_up_time(vin=vin)
                     > controller.update_interval
                 )

custom_components/tesla_custom/base.py

@@ -1,5 +1,6 @@
 """Support for Tesla cars and energy sites."""
 
+from homeassistant.core import callback
 from homeassistant.helpers.entity import DeviceInfo
 from homeassistant.helpers.update_coordinator import CoordinatorEntity
 from homeassistant.util import slugify
@@ -29,12 +30,6 @@ def __init__(
         self._attr_name = self.type.capitalize()
         self._attr_entity_registry_enabled_default = self._enabled_by_default
 
-    async def async_added_to_hass(self) -> None:
-        """Register state update callback."""
-        self.async_on_remove(
-            self.coordinator.async_add_listener(self.async_write_ha_state)
-        )
-
 
 class TeslaCarEntity(TeslaBaseEntity):
     """Representation of a Tesla car device."""
@@ -61,6 +56,27 @@ def __init__(
             model=car.car_type,
             sw_version=car.car_version,
         )
+        self._last_update_success: bool | None = None
+        self._last_controller_update_time: float | None = None
+
+    @callback
+    def _handle_coordinator_update(self) -> None:
+        """Handle updated data from the coordinator."""
+        prev_last_update_success = self._last_update_success
+        prev_last_controller_update_time = self._last_controller_update_time
+        coordinator = self.coordinator
+        current_last_update_success = coordinator.last_update_success
+        current_last_controller_update_time = coordinator.last_controller_update_time
+        self._last_update_success = current_last_update_success
+        self._last_controller_update_time = current_last_controller_update_time
+        if (
+            prev_last_update_success == current_last_update_success
+            and prev_last_controller_update_time == current_last_controller_update_time
+        ):
+            # If there was no change in the last update success or time,
+            # avoid writing state to prevent unnecessary entity updates.
+            return
+        super()._handle_coordinator_update()
 
     async def update_controller(
         self, *, wake_if_asleep: bool = False, force: bool = True, blocking: bool = True