Add mysensors state update delay (#18891)

* Add mysensors state update delay

* Schedule state update after delay to avoid updating state multiple
  times during the same short timespan.

* Code review

homeassistant/components/device_tracker/mysensors.py

@@ -14,7 +14,7 @@ async def async_setup_scanner(hass, config, async_see, discovery_info=None):
     """Set up the MySensors device scanner."""
     new_devices = mysensors.setup_mysensors_platform(
         hass, DOMAIN, discovery_info, MySensorsDeviceScanner,
-        device_args=(async_see, ))
+        device_args=(hass, async_see))
     if not new_devices:
         return False
 
@@ -37,12 +37,13 @@ async def async_setup_scanner(hass, config, async_see, discovery_info=None):
 class MySensorsDeviceScanner(mysensors.device.MySensorsDevice):
     """Represent a MySensors scanner."""
 
-    def __init__(self, async_see, *args):
+    def __init__(self, hass, async_see, *args):
         """Set up instance."""
         super().__init__(*args)
         self.async_see = async_see
+        self.hass = hass
 
-    async def async_update_callback(self):
+    async def _async_update_callback(self):
         """Update the device."""
         await self.async_update()
         node = self.gateway.sensors[self.node_id]

homeassistant/components/mysensors/const.py

@@ -23,6 +23,7 @@ SCHEMA = 'schema'
 CHILD_CALLBACK = 'mysensors_child_callback_{}_{}_{}_{}'
 NODE_CALLBACK = 'mysensors_node_callback_{}_{}'
 TYPE = 'type'
+UPDATE_DELAY = 0.1
 
 # MySensors const schemas
 BINARY_SENSOR_SCHEMA = {PLATFORM: 'binary_sensor', TYPE: 'V_TRIPPED'}

homeassistant/components/mysensors/device.py

@@ -1,5 +1,6 @@
 """Handle MySensors devices."""
 import logging
+from functools import partial
 
 from homeassistant.const import (
     ATTR_BATTERY_LEVEL, STATE_OFF, STATE_ON)
@@ -7,7 +8,7 @@ from homeassistant.core import callback
 from homeassistant.helpers.dispatcher import async_dispatcher_connect
 from homeassistant.helpers.entity import Entity
 
-from .const import CHILD_CALLBACK, NODE_CALLBACK
+from .const import CHILD_CALLBACK, NODE_CALLBACK, UPDATE_DELAY
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -39,6 +40,8 @@ class MySensorsDevice:
         child = gateway.sensors[node_id].children[child_id]
         self.child_type = child.type
         self._values = {}
+        self._update_scheduled = False
+        self.hass = None
 
     @property
     def name(self):
@@ -84,6 +87,29 @@ class MySensorsDevice:
             else:
                 self._values[value_type] = value
 
+    async def _async_update_callback(self):
+        """Update the device."""
+        raise NotImplementedError
+
+    @callback
+    def async_update_callback(self):
+        """Update the device after delay."""
+        if self._update_scheduled:
+            return
+
+        async def update():
+            """Perform update."""
+            try:
+                await self._async_update_callback()
+            except Exception:  # pylint: disable=broad-except
+                _LOGGER.exception("Error updating %s", self.name)
+            finally:
+                self._update_scheduled = False
+
+        self._update_scheduled = True
+        delayed_update = partial(self.hass.async_create_task, update())
+        self.hass.loop.call_later(UPDATE_DELAY, delayed_update)
+
 
 class MySensorsEntity(MySensorsDevice, Entity):
     """Representation of a MySensors entity."""
@@ -98,10 +124,9 @@ class MySensorsEntity(MySensorsDevice, Entity):
         """Return true if entity is available."""
         return self.value_type in self._values
 
-    @callback
-    def async_update_callback(self):
+    async def _async_update_callback(self):
         """Update the entity."""
-        self.async_schedule_update_ha_state(True)
+        await self.async_update_ha_state(True)
 
     async def async_added_to_hass(self):
         """Register update callback."""

homeassistant/components/mysensors/handler.py

@@ -99,7 +99,6 @@ def _handle_child_update(hass, hass_config, msg):
     for signal in set(signals):
         # Only one signal per device is needed.
         # A device can have multiple platforms, ie multiple schemas.
-        # FOR LATER: Add timer to not signal if another update comes in.
         async_dispatcher_send(hass, signal)