Cache the response from config/entity_registry/list (#74443)

homeassistant/components/config/entity_registry.py

@@ -1,11 +1,18 @@
 """HTTP views to interact with the entity registry."""
+from __future__ import annotations
+
 import voluptuous as vol
 
 from homeassistant import config_entries
 from homeassistant.components import websocket_api
 from homeassistant.components.websocket_api.const import ERR_NOT_FOUND
 from homeassistant.components.websocket_api.decorators import require_admin
-from homeassistant.core import callback
+from homeassistant.components.websocket_api.messages import (
+    IDEN_JSON_TEMPLATE,
+    IDEN_TEMPLATE,
+    message_to_json,
+)
+from homeassistant.core import Event, HomeAssistant, callback
 from homeassistant.helpers import (
     config_validation as cv,
     device_registry as dr,
@@ -13,8 +20,40 @@ from homeassistant.helpers import (
 )
 
 
-async def async_setup(hass):
+async def async_setup(hass: HomeAssistant) -> bool:
     """Enable the Entity Registry views."""
+
+    cached_list_entities: str | None = None
+
+    @callback
+    def _async_clear_list_entities_cache(event: Event) -> None:
+        nonlocal cached_list_entities
+        cached_list_entities = None
+
+    @websocket_api.websocket_command(
+        {vol.Required("type"): "config/entity_registry/list"}
+    )
+    @callback
+    def websocket_list_entities(hass, connection, msg):
+        """Handle list registry entries command."""
+        nonlocal cached_list_entities
+        if not cached_list_entities:
+            registry = er.async_get(hass)
+            cached_list_entities = message_to_json(
+                websocket_api.result_message(
+                    IDEN_TEMPLATE,
+                    [_entry_dict(entry) for entry in registry.entities.values()],
+                )
+            )
+        connection.send_message(
+            cached_list_entities.replace(IDEN_JSON_TEMPLATE, str(msg["id"]), 1)
+        )
+
+    hass.bus.async_listen(
+        er.EVENT_ENTITY_REGISTRY_UPDATED,
+        _async_clear_list_entities_cache,
+        run_immediately=True,
+    )
     websocket_api.async_register_command(hass, websocket_list_entities)
     websocket_api.async_register_command(hass, websocket_get_entity)
     websocket_api.async_register_command(hass, websocket_update_entity)
@@ -22,33 +61,6 @@ async def async_setup(hass):
     return True
 
 
-@websocket_api.websocket_command({vol.Required("type"): "config/entity_registry/list"})
-@callback
-def websocket_list_entities(hass, connection, msg):
-    """Handle list registry entries command."""
-    registry = er.async_get(hass)
-    connection.send_message(
-        websocket_api.result_message(
-            msg["id"],
-            [
-                {
-                    "area_id": entry.area_id,
-                    "config_entry_id": entry.config_entry_id,
-                    "device_id": entry.device_id,
-                    "disabled_by": entry.disabled_by,
-                    "entity_category": entry.entity_category,
-                    "entity_id": entry.entity_id,
-                    "hidden_by": entry.hidden_by,
-                    "icon": entry.icon,
-                    "name": entry.name,
-                    "platform": entry.platform,
-                }
-                for entry in registry.entities.values()
-            ],
-        )
-    )
-
-
 @websocket_api.websocket_command(
     {
         vol.Required("type"): "config/entity_registry/get",
@@ -211,7 +223,7 @@ def websocket_remove_entity(hass, connection, msg):
 
 
 @callback
-def _entry_ext_dict(entry):
+def _entry_dict(entry):
     """Convert entry to API format."""
     return {
         "area_id": entry.area_id,
@@ -224,12 +236,19 @@ def _entry_ext_dict(entry):
         "icon": entry.icon,
         "name": entry.name,
         "platform": entry.platform,
-        "capabilities": entry.capabilities,
-        "device_class": entry.device_class,
-        "has_entity_name": entry.has_entity_name,
-        "options": entry.options,
-        "original_device_class": entry.original_device_class,
-        "original_icon": entry.original_icon,
-        "original_name": entry.original_name,
-        "unique_id": entry.unique_id,
     }
+
+
+@callback
+def _entry_ext_dict(entry):
+    """Convert entry to API format."""
+    data = _entry_dict(entry)
+    data["capabilities"] = entry.capabilities
+    data["device_class"] = entry.device_class
+    data["has_entity_name"] = entry.has_entity_name
+    data["options"] = entry.options
+    data["original_device_class"] = entry.original_device_class
+    data["original_icon"] = entry.original_icon
+    data["original_name"] = entry.original_name
+    data["unique_id"] = entry.unique_id
+    return data

tests/components/config/test_entity_registry.py

@@ -5,6 +5,7 @@ from homeassistant.components.config import entity_registry
 from homeassistant.const import ATTR_ICON
 from homeassistant.helpers.device_registry import DeviceEntryDisabler
 from homeassistant.helpers.entity_registry import (
+    EVENT_ENTITY_REGISTRY_UPDATED,
     RegistryEntry,
     RegistryEntryDisabler,
     RegistryEntryHider,
@@ -81,6 +82,40 @@ async def test_list_entities(hass, client):
         },
     ]
 
+    mock_registry(
+        hass,
+        {
+            "test_domain.name": RegistryEntry(
+                entity_id="test_domain.name",
+                unique_id="1234",
+                platform="test_platform",
+                name="Hello World",
+            ),
+        },
+    )
+
+    hass.bus.async_fire(
+        EVENT_ENTITY_REGISTRY_UPDATED,
+        {"action": "create", "entity_id": "test_domain.no_name"},
+    )
+    await client.send_json({"id": 6, "type": "config/entity_registry/list"})
+    msg = await client.receive_json()
+
+    assert msg["result"] == [
+        {
+            "config_entry_id": None,
+            "device_id": None,
+            "area_id": None,
+            "disabled_by": None,
+            "entity_id": "test_domain.name",
+            "hidden_by": None,
+            "name": "Hello World",
+            "icon": None,
+            "platform": "test_platform",
+            "entity_category": None,
+        },
+    ]
+
 
 async def test_get_entity(hass, client):
     """Test get entry."""