old_contents: # Copyright 2011 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 nova import flags
  from nova import log as logging
  from nova.openstack.common import cfg
  from nova.openstack.common import exception as common_exception
  from nova.openstack.common import importutils
  
  
  list_notifier_drivers_opt = cfg.MultiStrOpt('list_notifier_drivers',
          default=['nova.notifier.no_op_notifier'],
          help='List of drivers to send notifications')
  
  FLAGS = flags.FLAGS
  FLAGS.register_opt(list_notifier_drivers_opt)
  
  LOG = logging.getLogger(__name__)
  
  drivers = None
  
  
  class ImportFailureNotifier(object):
      """Noisily re-raises some exception over-and-over when notify is called."""
  
      def __init__(self, exception):
          self.exception = exception
  
      def notify(self, message):
          raise self.exception
  
  
  def _get_drivers():
      """Instantiates and returns drivers based on the flag values."""
      global drivers
      if not drivers:
          drivers = []
          for notification_driver in FLAGS.list_notifier_drivers:
              try:
                  drivers.append(importutils.import_module(notification_driver))
              except ImportError as e:
                  drivers.append(ImportFailureNotifier(e))
      return drivers
  
  
  def notify(message):
      """Passes notification to multiple notifiers in a list."""
      for driver in _get_drivers():
          try:
              driver.notify(message)
          except Exception as e:
              LOG.exception(_("Problem '%(e)s' attempting to send to "
                              "notification driver %(driver)s."), locals())
  
  
  def _reset_drivers():
      """Used by unit tests to reset the drivers."""
      global drivers
      drivers = None
  
new_contents: # Copyright 2011 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 nova import flags
  from nova import log as logging
  from nova.openstack.common import cfg
  from nova.openstack.common import importutils
  
  
  list_notifier_drivers_opt = cfg.MultiStrOpt('list_notifier_drivers',
          default=['nova.notifier.no_op_notifier'],
          help='List of drivers to send notifications')
  
  FLAGS = flags.FLAGS
  FLAGS.register_opt(list_notifier_drivers_opt)
  
  LOG = logging.getLogger(__name__)
  
  drivers = None
  
  
  class ImportFailureNotifier(object):
      """Noisily re-raises some exception over-and-over when notify is called."""
  
      def __init__(self, exception):
          self.exception = exception
  
      def notify(self, message):
          raise self.exception
  
  
  def _get_drivers():
      """Instantiates and returns drivers based on the flag values."""
      global drivers
      if not drivers:
          drivers = []
          for notification_driver in FLAGS.list_notifier_drivers:
              try:
                  drivers.append(importutils.import_module(notification_driver))
              except ImportError as e:
                  drivers.append(ImportFailureNotifier(e))
      return drivers
  
  
  def notify(message):
      """Passes notification to multiple notifiers in a list."""
      for driver in _get_drivers():
          try:
              driver.notify(message)
          except Exception as e:
              LOG.exception(_("Problem '%(e)s' attempting to send to "
                              "notification driver %(driver)s."), locals())
  
  
  def _reset_drivers():
      """Used by unit tests to reset the drivers."""
      global drivers
      drivers = None
  
subject: Update common.importutils from openstack-common.