Synchronize attribute reads and subscriptions on startup (#17)

* Synchronize attribute reads and subscriptions on startup

Avoid multiple entities requesting reads and subscriptions of the same
node. Nodes seem to be overwhelmed and return a BUSY error code, which
isn't handled gracefully throughout the stack (it seems).

* Store Node Lock in the HA Adapter

custom_components/matter_experimental/adapter.py

@@ -114,6 +114,7 @@ def __init__(self, hass: HomeAssistant, config_entry: ConfigEntry) -> None:
         self._fallback_store = get_matter_fallback_store(hass, config_entry)
         self.platform_handlers: dict[Platform, AddEntitiesCallback] = {}
         self._platforms_set_up = asyncio.Event()
+        self._node_lock: dict[int, asyncio.Lock] = {}
 
     def register_platform_handler(
         self, platform: Platform, add_entities: AddEntitiesCallback
@@ -149,6 +150,11 @@ def get_server_url(self) -> str:
     def get_client_session(self) -> aiohttp.ClientSession:
         return async_get_clientsession(self.hass)
 
+    def get_node_lock(self, nodeid) -> asyncio.Lock:
+        if nodeid not in self._node_lock:
+            self._node_lock[nodeid] = asyncio.Lock()
+        return self._node_lock[nodeid]
+
     async def setup_node(self, node: MatterNode) -> None:
         """Set up an node."""
         await self._platforms_set_up.wait()

custom_components/matter_experimental/entity.py

@@ -30,10 +30,8 @@ def device_info(self) -> entity.DeviceInfo | None:
         """Return device info for device registry."""
         return {"identifiers": {(DOMAIN, self._device.node.unique_id)}}
 
-    async def async_added_to_hass(self) -> None:
-        """Handle being added to Home Assistant."""
-        await super().async_added_to_hass()
-
+    async def init_matter_device(self) -> None:
+        """Initialize and subscribe device attributes."""
         device_name = (
             device_registry.async_get(self.hass)
             .async_get(self.registry_entry.device_id)
@@ -80,6 +78,15 @@ async def async_added_to_hass(self) -> None:
 
         self._update_from_device()
 
+    async def async_added_to_hass(self) -> None:
+        """Handle being added to Home Assistant."""
+        await super().async_added_to_hass()
+
+        async with self._device.node.matter.adapter.get_node_lock(
+            self._device.node.node_id
+        ):
+            await self.init_matter_device()
+
     async def async_will_remove_from_hass(self) -> None:
         """Run when entity will be removed from hass."""
         if self._unsubscribe is not None: