Notification refactoring

gistfile1.py

    def send_stack_usage_even(self, event_type, **kwargs):        
        az = kwargs.pop('az')
        name = kwargs.pop('name')
        event_type = 'trove.instance.%s' % event_type
        publisher_id = CONF.host
        created_time = timeutils.isotime(self.db_info.created)        
        compute_instance_id = kwargs.pop('compute_instance_id')
        payload = {'availability_zone': az,
                   'created_at': created_time,
                   'name': name,
                   'instance_id': self.id,
                   'instance_name': name,
                   'flavor_name': self.new_flavor['name'],
                   'flavor_id': self.new_flavor['id'],
                   'launched_at': created_time,
                   'compute_instance_id': compute_instance_id,
                   'region': CONF.region,
                   'state_description': self.status.description,
                   'state': self.status, 
                   'tenant_id': self.tenant_id,
                   'user_id': self.context.user,
                   'service_id': self._get_service_id(
                       self.datastore_version.manager,
                       CONF.notification_service_id)}

        if CONF.trove_volume_support:
            payload.update({
                'volume_size': self.db_info.volume_size,
                'volume_id': self.db_info.volume_id
            })

        # Update payload with all other kwargs
        payload.update(kwargs)
        LOG.debug(_('Sending event: %(event_type)s, %(payload)s') %
                  {'event_type': event_type, 'payload': payload})
        notifier.notify(self.context, publisher_id, event_type, 'INFO',
                        payload)