Initial script condition support (#1910)

homeassistant/components/automation/event.py

@@ -6,20 +6,26 @@ at https://home-assistant.io/components/automation/#event-trigger
 """
 import logging
 
+import voluptuous as vol
+
+from homeassistant.const import CONF_PLATFORM
+from homeassistant.helpers import config_validation as cv
+
 CONF_EVENT_TYPE = "event_type"
 CONF_EVENT_DATA = "event_data"
 
 _LOGGER = logging.getLogger(__name__)
 
+TRIGGER_SCHEMA = vol.Schema({
+    vol.Required(CONF_PLATFORM): 'event',
+    vol.Required(CONF_EVENT_TYPE): cv.string,
+    vol.Optional(CONF_EVENT_DATA): dict,
+})
+
 
 def trigger(hass, config, action):
     """Listen for events based on configuration."""
     event_type = config.get(CONF_EVENT_TYPE)
-
-    if event_type is None:
-        _LOGGER.error("Missing configuration key %s", CONF_EVENT_TYPE)
-        return False
-
     event_data = config.get(CONF_EVENT_DATA)
 
     def handle_event(event):