Merge remote-tracking branch 'balloob/dev' into automation-decorator

# Conflicts:
#	homeassistant/helpers/service.py
#	tests/helpers/test_service.py

homeassistant/helpers/service.py

@@ -2,8 +2,9 @@
 import functools
 import logging
 
-from homeassistant.util import split_entity_id
 from homeassistant.const import ATTR_ENTITY_ID
+from homeassistant.helpers.entity import split_entity_id
+from homeassistant.loader import get_component
 
 HASS = None
 
@@ -61,3 +62,22 @@ def call_from_config(hass, config, blocking=False):
         service_data[ATTR_ENTITY_ID] = entity_id
 
     hass.services.call(domain, service_name, service_data, blocking)
+
+
+def extract_entity_ids(hass, service):
+    """
+    Helper method to extract a list of entity ids from a service call.
+    Will convert group entity ids to the entity ids it represents.
+    """
+    if not (service.data and ATTR_ENTITY_ID in service.data):
+        return []
+
+    group = get_component('group')
+
+    # Entity ID attr can be a list or a string
+    service_ent_id = service.data[ATTR_ENTITY_ID]
+
+    if isinstance(service_ent_id, str):
+        return group.expand_entity_ids(hass, [service_ent_id])
+
+    return [ent_id for ent_id in group.expand_entity_ids(hass, service_ent_id)]