text: # Copyright 2011 Justin Santa Barbara
  # 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.
  
  """The volumes snapshots api."""
  from http import client as http_client
  
  from oslo_log import log as logging
  from oslo_utils import strutils
  import webob
  
  from cinder.api import api_utils
  from cinder.api import common
  from cinder.api.openstack import wsgi
  from cinder.api.schemas import snapshots as snapshot
  from cinder.api import validation
  from cinder.api.views import snapshots as snapshot_views
  from cinder import volume
  from cinder.volume import volume_utils
  
  
  LOG = logging.getLogger(__name__)
  
  
  class SnapshotsController(wsgi.Controller):
      """The Snapshots API controller for the OpenStack API."""
  
      _view_builder_class = snapshot_views.ViewBuilder
  
      def __init__(self, ext_mgr=None):
          self.volume_api = volume.API()
          self.ext_mgr = ext_mgr
          super(SnapshotsController, self).__init__()
  
      def show(self, req, id):
          """Return data about the given snapshot."""
          context = req.environ['cinder.context']
  
          # Not found exception will be handled at the wsgi level
          snapshot = self.volume_api.get_snapshot(context, id)
          req.cache_db_snapshot(snapshot)
  
          return self._view_builder.detail(req, snapshot)
  
      def delete(self, req, id):
          """Delete a snapshot."""
          context = req.environ['cinder.context']
  
          LOG.info("Delete snapshot with id: %s", id)
  
          # Not found exception will be handled at the wsgi level
          snapshot = self.volume_api.get_snapshot(context, id)
          self.volume_api.delete_snapshot(context, snapshot)
  
          return webob.Response(status_int=http_client.ACCEPTED)
  
      def index(self, req):
          """Returns a summary list of snapshots."""
          return self._items(req, is_detail=False)
  
      def detail(self, req):
          """Returns a detailed list of snapshots."""
          return self._items(req, is_detail=True)
  
      def _items(self, req, is_detail=True):
          """Returns a list of snapshots, transformed through view builder."""
          context = req.environ['cinder.context']
  
          # Pop out non search_opts and create local variables
          search_opts = req.GET.copy()
          sort_keys, sort_dirs = common.get_sort_params(search_opts)
          marker, limit, offset = common.get_pagination_params(search_opts)
  
          # Filter out invalid options
          allowed_search_options = ('status', 'volume_id', 'name')
          api_utils.remove_invalid_filter_options(context, search_opts,
                                                  allowed_search_options)
  
          # NOTE(thingee): v2 API allows name instead of display_name
          if 'name' in search_opts:
              search_opts['display_name'] = search_opts.pop('name')
  
          snapshots = self.volume_api.get_all_snapshots(context,
                                                        search_opts=search_opts,
                                                        marker=marker,
                                                        limit=limit,
                                                        sort_keys=sort_keys,
                                                        sort_dirs=sort_dirs,
                                                        offset=offset)
  
          req.cache_db_snapshots(snapshots.objects)
  
          if is_detail:
              snapshots = self._view_builder.detail_list(req, snapshots.objects)
          else:
              snapshots = self._view_builder.summary_list(req, snapshots.objects)
          return snapshots
  
      @wsgi.response(http_client.ACCEPTED)
      @validation.schema(snapshot.create)
      def create(self, req, body):
          """Creates a new snapshot."""
          kwargs = {}
          context = req.environ['cinder.context']
          snapshot = body['snapshot']
          kwargs['metadata'] = snapshot.get('metadata', None)
          volume_id = snapshot['volume_id']
          volume = self.volume_api.get(context, volume_id)
          force = snapshot.get('force', False)
          force = strutils.bool_from_string(force, strict=True)
          LOG.info("Create snapshot from volume %s", volume_id)
  
          self.validate_name_and_description(snapshot, check_length=False)
          # NOTE(thingee): v2 API allows name instead of display_name
          if 'name' in snapshot:
              snapshot['display_name'] = snapshot.pop('name')
  
          if force:
              new_snapshot = self.volume_api.create_snapshot_force(
                  context,
                  volume,
                  snapshot.get('display_name'),
                  snapshot.get('description'),
                  **kwargs)
          else:
              new_snapshot = self.volume_api.create_snapshot(
                  context,
                  volume,
                  snapshot.get('display_name'),
                  snapshot.get('description'),
                  **kwargs)
          req.cache_db_snapshot(new_snapshot)
  
          return self._view_builder.detail(req, new_snapshot)
  
      @validation.schema(snapshot.update)
      def update(self, req, id, body):
          """Update a snapshot."""
          context = req.environ['cinder.context']
          snapshot_body = body['snapshot']
          self.validate_name_and_description(snapshot_body, check_length=False)
  
          if 'name' in snapshot_body:
              snapshot_body['display_name'] = snapshot_body.pop('name')
  
          if 'description' in snapshot_body:
              snapshot_body['display_description'] = snapshot_body.pop(
                  'description')
  
          # Not found exception will be handled at the wsgi level
          snapshot = self.volume_api.get_snapshot(context, id)
          volume_utils.notify_about_snapshot_usage(context, snapshot,
                                                   'update.start')
          self.volume_api.update_snapshot(context, snapshot, snapshot_body)
  
          snapshot.update(snapshot_body)
          req.cache_db_snapshot(snapshot)
          volume_utils.notify_about_snapshot_usage(context, snapshot,
                                                   'update.end')
  
          return self._view_builder.detail(req, snapshot)
  
  
  def create_resource(ext_mgr):
      return wsgi.Resource(SnapshotsController(ext_mgr))
  