Convert template switch to use async_track_template_result (#38950)

homeassistant/components/template/sensor.py

@@ -27,7 +27,7 @@ import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.entity import Entity, async_generate_entity_id
 
 from .const import CONF_AVAILABILITY_TEMPLATE
-from .template_entity import TemplateEntityWithAvailability
+from .template_entity import TemplateEntityWithAvailabilityAndImages
 
 CONF_ATTRIBUTE_TEMPLATES = "attribute_templates"
 
@@ -94,7 +94,7 @@ async def async_setup_platform(hass, config, async_add_entities, discovery_info=
     return True
 
 
-class SensorTemplate(TemplateEntityWithAvailability, Entity):
+class SensorTemplate(TemplateEntityWithAvailabilityAndImages, Entity):
     """Representation of a Template Sensor."""
 
     def __init__(
@@ -113,7 +113,7 @@ class SensorTemplate(TemplateEntityWithAvailability, Entity):
         unique_id,
     ):
         """Initialize the sensor."""
-        super().__init__(availability_template)
+        super().__init__(availability_template, icon_template, entity_picture_template)
         self.entity_id = async_generate_entity_id(
             ENTITY_ID_FORMAT, device_id, hass=hass
         )
@@ -122,10 +122,6 @@ class SensorTemplate(TemplateEntityWithAvailability, Entity):
         self._unit_of_measurement = unit_of_measurement
         self._template = state_template
         self._state = None
-        self._icon_template = icon_template
-        self._entity_picture_template = entity_picture_template
-        self._icon = None
-        self._entity_picture = None
         self._device_class = device_class
         self._attribute_templates = attribute_templates
         self._attributes = {}
@@ -135,14 +131,6 @@ class SensorTemplate(TemplateEntityWithAvailability, Entity):
         """Register callbacks."""
 
         self.add_template_attribute("_state", self._template, None, self._update_state)
-        if self._icon_template is not None:
-            self.add_template_attribute(
-                "_icon", self._icon_template, vol.Or(cv.whitespace, cv.icon)
-            )
-        if self._entity_picture_template is not None:
-            self.add_template_attribute(
-                "_entity_picture", self._entity_picture_template
-            )
         if self._friendly_name_template is not None:
             self.add_template_attribute("_name", self._friendly_name_template)
 
@@ -181,21 +169,11 @@ class SensorTemplate(TemplateEntityWithAvailability, Entity):
         """Return the state of the sensor."""
         return self._state
 
-    @property
-    def icon(self):
-        """Return the icon to use in the frontend, if any."""
-        return self._icon
-
     @property
     def device_class(self) -> Optional[str]:
         """Return the device class of the sensor."""
         return self._device_class
 
-    @property
-    def entity_picture(self):
-        """Return the entity_picture to use in the frontend, if any."""
-        return self._entity_picture
-
     @property
     def unit_of_measurement(self):
         """Return the unit_of_measurement of the device."""

homeassistant/components/template/switch.py

@@ -16,8 +16,6 @@ from homeassistant.const import (
     CONF_SWITCHES,
     CONF_UNIQUE_ID,
     CONF_VALUE_TEMPLATE,
-    EVENT_HOMEASSISTANT_START,
-    MATCH_ALL,
     STATE_OFF,
     STATE_ON,
 )
@@ -25,12 +23,11 @@ from homeassistant.core import callback
 from homeassistant.exceptions import TemplateError
 import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.entity import async_generate_entity_id
-from homeassistant.helpers.event import async_track_state_change_event
 from homeassistant.helpers.restore_state import RestoreEntity
 from homeassistant.helpers.script import Script
 
-from . import extract_entities, initialise_templates
 from .const import CONF_AVAILABILITY_TEMPLATE
+from .template_entity import TemplateEntityWithAvailabilityAndImages
 
 _LOGGER = logging.getLogger(__name__)
 _VALID_STATES = [STATE_ON, STATE_OFF, "true", "false"]
@@ -71,18 +68,6 @@ async def async_setup_platform(hass, config, async_add_entities, discovery_info=
         off_action = device_config[OFF_ACTION]
         unique_id = device_config.get(CONF_UNIQUE_ID)
 
-        templates = {
-            CONF_VALUE_TEMPLATE: state_template,
-            CONF_ICON_TEMPLATE: icon_template,
-            CONF_ENTITY_PICTURE_TEMPLATE: entity_picture_template,
-            CONF_AVAILABILITY_TEMPLATE: availability_template,
-        }
-
-        initialise_templates(hass, templates)
-        entity_ids = extract_entities(
-            device, "switch", device_config.get(ATTR_ENTITY_ID), templates
-        )
-
         switches.append(
             SwitchTemplate(
                 hass,
@@ -94,7 +79,6 @@ async def async_setup_platform(hass, config, async_add_entities, discovery_info=
                 availability_template,
                 on_action,
                 off_action,
-                entity_ids,
                 unique_id,
             )
         )
@@ -102,7 +86,9 @@ async def async_setup_platform(hass, config, async_add_entities, discovery_info=
     async_add_entities(switches)
 
 
-class SwitchTemplate(SwitchEntity, RestoreEntity):
+class SwitchTemplate(
+    TemplateEntityWithAvailabilityAndImages, SwitchEntity, RestoreEntity
+):
     """Representation of a Template switch."""
 
     def __init__(
@@ -116,11 +102,10 @@ class SwitchTemplate(SwitchEntity, RestoreEntity):
         availability_template,
         on_action,
         off_action,
-        entity_ids,
         unique_id,
     ):
         """Initialize the Template switch."""
-        self.hass = hass
+        super().__init__(availability_template, icon_template, entity_picture_template)
         self.entity_id = async_generate_entity_id(
             ENTITY_ID_FORMAT, device_id, hass=hass
         )
@@ -130,15 +115,16 @@ class SwitchTemplate(SwitchEntity, RestoreEntity):
         self._on_script = Script(hass, on_action, friendly_name, domain)
         self._off_script = Script(hass, off_action, friendly_name, domain)
         self._state = False
-        self._icon_template = icon_template
-        self._entity_picture_template = entity_picture_template
-        self._availability_template = availability_template
-        self._icon = None
-        self._entity_picture = None
-        self._entities = entity_ids
-        self._available = True
         self._unique_id = unique_id
 
+    @callback
+    def _update_state(self, result):
+        super()._update_state(result)
+        if isinstance(result, TemplateError):
+            self._state = None
+            return
+        self._state = result.lower() in ("true", STATE_ON)
+
     async def async_added_to_hass(self):
         """Register callbacks."""
 
@@ -151,28 +137,12 @@ class SwitchTemplate(SwitchEntity, RestoreEntity):
                 self._state = state.state == STATE_ON
 
             # no need to listen for events
-            return
+        else:
-
+            self.add_template_attribute(
-        # set up event listening
+                "_state", self._template, None, self._update_state
-        @callback
-        def template_switch_state_listener(event):
-            """Handle target device state changes."""
-            self.async_schedule_update_ha_state(True)
-
-        @callback
-        def template_switch_startup(event):
-            """Update template on startup."""
-            if self._entities != MATCH_ALL:
-                # Track state change only for valid templates
-                async_track_state_change_event(
-                    self.hass, self._entities, template_switch_state_listener
             )
 
-            self.async_schedule_update_ha_state(True)
+        await super().async_added_to_hass()
-
-        self.hass.bus.async_listen_once(
-            EVENT_HOMEASSISTANT_START, template_switch_startup
-        )
 
     @property
     def name(self):
@@ -194,21 +164,6 @@ class SwitchTemplate(SwitchEntity, RestoreEntity):
         """Return the polling state."""
         return False
 
-    @property
-    def icon(self):
-        """Return the icon to use in the frontend, if any."""
-        return self._icon
-
-    @property
-    def entity_picture(self):
-        """Return the entity_picture to use in the frontend, if any."""
-        return self._entity_picture
-
-    @property
-    def available(self) -> bool:
-        """Return if the device is available."""
-        return self._available
-
     async def async_turn_on(self, **kwargs):
         """Fire the on action."""
         await self._on_script.async_run(context=self._context)
@@ -223,63 +178,6 @@ class SwitchTemplate(SwitchEntity, RestoreEntity):
             self._state = False
             self.async_write_ha_state()
 
-    async def async_update(self):
-        """Update the state from the template."""
-        if self._template is None:
-            return
-        try:
-            state = self._template.async_render().lower()
-
-            if state in _VALID_STATES:
-                self._state = state in ("true", STATE_ON)
-            else:
-                _LOGGER.error(
-                    "Received invalid switch is_on state: %s. Expected: %s",
-                    state,
-                    ", ".join(_VALID_STATES),
-                )
-                self._state = None
-
-        except TemplateError as ex:
-            _LOGGER.error(ex)
-            self._state = None
-
-        for property_name, template in (
-            ("_icon", self._icon_template),
-            ("_entity_picture", self._entity_picture_template),
-            ("_available", self._availability_template),
-        ):
-            if template is None:
-                continue
-
-            try:
-                value = template.async_render()
-                if property_name == "_available":
-                    value = value.lower() == "true"
-                setattr(self, property_name, value)
-            except TemplateError as ex:
-                friendly_property_name = property_name[1:].replace("_", " ")
-                if ex.args and ex.args[0].startswith(
-                    "UndefinedError: 'None' has no attribute"
-                ):
-                    # Common during HA startup - so just a warning
-                    _LOGGER.warning(
-                        "Could not render %s template %s, the state is unknown",
-                        friendly_property_name,
-                        self._name,
-                    )
-                    return
-
-                try:
-                    setattr(self, property_name, getattr(super(), property_name))
-                except AttributeError:
-                    _LOGGER.error(
-                        "Could not render %s template %s: %s",
-                        friendly_property_name,
-                        self._name,
-                        ex,
-                    )
-
     @property
     def assumed_state(self):
         """State is assumed, if no template given."""

homeassistant/components/template/template_entity.py

@@ -7,6 +7,7 @@ import voluptuous as vol
 
 from homeassistant.core import EVENT_HOMEASSISTANT_START, callback
 from homeassistant.exceptions import TemplateError
+import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.config_validation import match_all
 from homeassistant.helpers.entity import Entity
 from homeassistant.helpers.event import Event, async_track_template_result
@@ -221,3 +222,38 @@ class TemplateEntityWithAvailability(TemplateEntity):
             )
 
         await super().async_added_to_hass()
+
+
+class TemplateEntityWithAvailabilityAndImages(TemplateEntityWithAvailability):
+    """Entity that uses templates to calculate attributes with an availability, icon, and images template."""
+
+    def __init__(self, availability_template, icon_template, entity_picture_template):
+        """Template Entity."""
+        self._icon_template = icon_template
+        self._entity_picture_template = entity_picture_template
+        self._icon = None
+        self._entity_picture = None
+        super().__init__(availability_template)
+
+    @property
+    def icon(self):
+        """Return the icon to use in the frontend, if any."""
+        return self._icon
+
+    @property
+    def entity_picture(self):
+        """Return the entity_picture to use in the frontend, if any."""
+        return self._entity_picture
+
+    async def async_added_to_hass(self):
+        """Register callbacks."""
+        if self._icon_template is not None:
+            self.add_template_attribute(
+                "_icon", self._icon_template, vol.Or(cv.whitespace, cv.icon)
+            )
+        if self._entity_picture_template is not None:
+            self.add_template_attribute(
+                "_entity_picture", self._entity_picture_template
+            )
+
+        await super().async_added_to_hass()