Reorganize trigger code (#38655)

homeassistant/helpers/trigger.py

@@ -0,0 +1,92 @@
+"""Triggers."""
+import asyncio
+import logging
+from typing import Any, Callable, List, Optional
+
+import voluptuous as vol
+
+from homeassistant.const import CONF_PLATFORM
+from homeassistant.core import CALLBACK_TYPE, callback
+from homeassistant.helpers.typing import ConfigType, HomeAssistantType
+from homeassistant.loader import IntegrationNotFound, async_get_integration
+
+_PLATFORM_ALIASES = {
+    "device_automation": ("device",),
+    "homeassistant": ("event", "numeric_state", "state", "time_pattern", "time"),
+}
+
+
+async def _async_get_trigger_platform(
+    hass: HomeAssistantType, config: ConfigType
+) -> Any:
+    platform = config[CONF_PLATFORM]
+    for alias, triggers in _PLATFORM_ALIASES.items():
+        if platform in triggers:
+            platform = alias
+            break
+    try:
+        integration = await async_get_integration(hass, platform)
+    except IntegrationNotFound:
+        raise vol.Invalid(f"Invalid platform '{platform}' specified") from None
+    try:
+        return integration.get_platform("trigger")
+    except ImportError:
+        raise vol.Invalid(
+            f"Integration '{platform}' does not provide trigger support"
+        ) from None
+
+
+async def async_validate_trigger_config(
+    hass: HomeAssistantType, trigger_config: List[ConfigType]
+) -> List[ConfigType]:
+    """Validate triggers."""
+    config = []
+    for conf in trigger_config:
+        platform = await _async_get_trigger_platform(hass, conf)
+        if hasattr(platform, "async_validate_trigger_config"):
+            conf = await platform.async_validate_trigger_config(hass, conf)
+        else:
+            conf = platform.TRIGGER_SCHEMA(conf)
+        config.append(conf)
+    return config
+
+
+async def async_initialize_triggers(
+    hass: HomeAssistantType,
+    trigger_config: List[ConfigType],
+    action: Callable,
+    domain: str,
+    name: str,
+    log_cb: Callable,
+    home_assistant_start: bool = False,
+) -> Optional[CALLBACK_TYPE]:
+    """Initialize triggers."""
+    info = {
+        "domain": domain,
+        "name": name,
+        "home_assistant_start": home_assistant_start,
+    }
+
+    triggers = []
+    for conf in trigger_config:
+        platform = await _async_get_trigger_platform(hass, conf)
+        triggers.append(platform.async_attach_trigger(hass, conf, action, info))
+
+    removes = await asyncio.gather(*triggers)
+
+    if None in removes:
+        log_cb(logging.ERROR, "Error setting up trigger")
+
+    removes = list(filter(None, removes))
+    if not removes:
+        return None
+
+    log_cb(logging.INFO, "Initialized trigger")
+
+    @callback
+    def remove_triggers():  # type: ignore
+        """Remove triggers."""
+        for remove in removes:
+            remove()
+
+    return remove_triggers