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diff --git a/openstack/common/plugin/callbackplugin.py b/openstack/common/plugin/callbackplugin.py
new file mode 100644
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+++ b/openstack/common/plugin/callbackplugin.py
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+# Copyright 2012 OpenStack LLC.
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from openstack.common.plugin import plugin
+from openstack.common import log as logging
+
+
+LOG = logging.getLogger(__name__)
+
+
+class _CallbackNotifier(object):
+    """Manages plugin-defined notification callbacks.
+
+    For each Plugin, a CallbackNotifier will be added to the
+    notification driver list.  Calls to notify() with appropriate
+    messages will be hooked and prompt callbacks.
+
+    A callback should look like this:
+      def callback(context, message, user_data)
+    """
+
+    def __init__(self):
+        self._callback_dict = {}
+
+    def _add_callback(self, event_type, callback, user_data):
+        callback_list = self._callback_dict.get(event_type, [])
+        callback_list.append({'function': callback,
+                              'user_data': user_data})
+        self._callback_dict[event_type] = callback_list
+
+    def _remove_callback(self, callback):
+        for callback_list in self._callback_dict.values():
+            for entry in callback_list:
+                if entry['function'] == callback:
+                    callback_list.remove(entry)
+
+    def notify(self, context, message):
+        if message.get('event_type') not in self._callback_dict:
+            return
+
+        for entry in self._callback_dict[message.get('event_type')]:
+            entry['function'](context, message, entry.get('user_data'))
+
+    def callbacks(self):
+        return self._callback_dict
+
+
+class CallbackPlugin(plugin.Plugin):
+    """ Plugin with a simple callback interface.
+
+    This class is provided as a convenience for producing a simple
+    plugin that only watches a couple of events.  For example, here's
+    a subclass which prints a line the first time an instance is created.
+
+    class HookInstanceCreation(CallbackPlugin):
+
+        def __init__(self, _service_name):
+            super(HookInstanceCreation, self).__init__()
+            self._add_callback(self.magic, 'compute.instance.create.start')
+
+        def magic(self):
+            print "An instance was created!"
+            self._remove_callback(self, self.magic)
+    """
+
+    def __init__(self, service_name):
+        super(CallbackPlugin, self).__init__(service_name)
+        self._callback_notifier = _CallbackNotifier()
+        self._add_notifier(self._callback_notifier)
+
+    def _add_callback(self, callback, event_type, user_data=None):
+        """Add callback for a given event notification.
+
+        Subclasses can call this as an alternative to implementing
+        a fullblown notify notifier.
+        """
+        self._callback_notifier._add_callback(event_type, callback, user_data)
+
+    def _remove_callback(self, callback):
+        """Remove all notification callbacks to specified function."""
+        self._callback_notifier._remove_callback(callback)