Add loader.async_get_loaded_integration (#99440)

* Add loader.async_get_loaded_integration

* Decorate async_get_loaded_integration with @callback

homeassistant/core.py

@@ -32,7 +32,7 @@ from urllib.parse import urlparse
 import voluptuous as vol
 import yarl
 
-from . import block_async_io, loader, util
+from . import block_async_io, util
 from .const import (
     ATTR_DOMAIN,
     ATTR_FRIENDLY_NAME,
@@ -310,6 +310,9 @@ class HomeAssistant:
 
     def __init__(self, config_dir: str) -> None:
         """Initialize new Home Assistant object."""
+        # pylint: disable-next=import-outside-toplevel
+        from . import loader
+
         self.loop = asyncio.get_running_loop()
         self._tasks: set[asyncio.Future[Any]] = set()
         self._background_tasks: set[asyncio.Future[Any]] = set()

homeassistant/loader.py

@@ -25,6 +25,7 @@ from awesomeversion import (
 import voluptuous as vol
 
 from . import generated
+from .core import HomeAssistant, callback
 from .generated.application_credentials import APPLICATION_CREDENTIALS
 from .generated.bluetooth import BLUETOOTH
 from .generated.dhcp import DHCP
@@ -37,7 +38,6 @@ from .util.json import JSON_DECODE_EXCEPTIONS, json_loads
 # Typing imports that create a circular dependency
 if TYPE_CHECKING:
     from .config_entries import ConfigEntry
-    from .core import HomeAssistant
     from .helpers import device_registry as dr
     from .helpers.typing import ConfigType
 
@@ -875,6 +875,22 @@ def _resolve_integrations_from_root(
     return integrations
 
 
+@callback
+def async_get_loaded_integration(hass: HomeAssistant, domain: str) -> Integration:
+    """Get an integration which is already loaded.
+
+    Raises IntegrationNotLoaded if the integration is not loaded.
+    """
+    cache = hass.data[DATA_INTEGRATIONS]
+    if TYPE_CHECKING:
+        cache = cast(dict[str, Integration | asyncio.Future[None]], cache)
+    int_or_fut = cache.get(domain, _UNDEF)
+    # Integration is never subclassed, so we can check for type
+    if type(int_or_fut) is Integration:  # noqa: E721
+        return int_or_fut
+    raise IntegrationNotLoaded(domain)
+
+
 async def async_get_integration(hass: HomeAssistant, domain: str) -> Integration:
     """Get integration."""
     integrations_or_excs = await async_get_integrations(hass, [domain])
@@ -970,6 +986,15 @@ class IntegrationNotFound(LoaderError):
         self.domain = domain
 
 
+class IntegrationNotLoaded(LoaderError):
+    """Raised when a component is not loaded."""
+
+    def __init__(self, domain: str) -> None:
+        """Initialize a component not found error."""
+        super().__init__(f"Integration '{domain}' not loaded.")
+        self.domain = domain
+
+
 class CircularDependency(LoaderError):
     """Raised when a circular dependency is found when resolving components."""
 

tests/test_loader.py

@@ -150,10 +150,17 @@ async def test_custom_integration_version_not_valid(
 
 async def test_get_integration(hass: HomeAssistant) -> None:
     """Test resolving integration."""
+    with pytest.raises(loader.IntegrationNotLoaded):
+        loader.async_get_loaded_integration(hass, "hue")
+
     integration = await loader.async_get_integration(hass, "hue")
     assert hue == integration.get_component()
     assert hue_light == integration.get_platform("light")
 
+    integration = loader.async_get_loaded_integration(hass, "hue")
+    assert hue == integration.get_component()
+    assert hue_light == integration.get_platform("light")
+
 
 async def test_get_integration_exceptions(hass: HomeAssistant) -> None:
     """Test resolving integration."""