Merge "Callbacks: add precommit support"

neutron_lib/_callbacks/events.py

@@ -16,6 +16,10 @@ BEFORE_READ = 'before_read'
 BEFORE_UPDATE = 'before_update'
 BEFORE_DELETE = 'before_delete'
 
+PRECOMMIT_CREATE = 'precommit_create'
+PRECOMMIT_UPDATE = 'precommit_update'
+PRECOMMIT_DELETE = 'precommit_delete'
+
 AFTER_CREATE = 'after_create'
 AFTER_READ = 'after_read'
 AFTER_UPDATE = 'after_update'
@@ -28,3 +32,4 @@ ABORT_DELETE = 'abort_delete'
 
 ABORT = 'abort_'
 BEFORE = 'before_'
+PRECOMMIT = 'precommit_'

neutron_lib/_callbacks/manager.py

@@ -116,11 +116,16 @@ class CallbacksManager(object):
         :param trigger: the trigger. A reference to the sender of the event.
         """
         errors = self._notify_loop(resource, event, trigger, **kwargs)
-        if errors and event.startswith(events.BEFORE):
-            abort_event = event.replace(
-                events.BEFORE, events.ABORT)
-            self._notify_loop(resource, abort_event, trigger)
-            raise exceptions.CallbackFailure(errors=errors)
+        if errors:
+            if event.startswith(events.BEFORE):
+                abort_event = event.replace(
+                    events.BEFORE, events.ABORT)
+                self._notify_loop(resource, abort_event, trigger, **kwargs)
+
+                raise exceptions.CallbackFailure(errors=errors)
+
+            if event.startswith(events.PRECOMMIT):
+                raise exceptions.CallbackFailure(errors=errors)
 
     def clear(self):
         """Brings the manager to a clean slate."""