nova/nova/objects/instance_mapping.py
Andrew Laski 12b481a668 Add InstanceMapping object
This adds the InstanceMapping object for interacting with the
instance_mapping table.

Rather than creating a new db api the database operations are embedded
within the object.  This keeps the logic near where it's being used.
This does make an assumption about using sqlalchemy for now.  In order
to allow for substituting the database driver we will probably want to
setup a subclassing system for objects to swap that part out.  This
would allow for finer control than we currently have.

Change-Id: Ide9cc7a255b886647fd424c2030beff0335e2cd3
bp: cells-v2-mapping
2015-03-18 15:24:25 -04:00

137 lines
4.6 KiB
Python

# 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.db.sqlalchemy import api as db_api
from nova.db.sqlalchemy import api_models
from nova import exception
from nova import objects
from nova.objects import base
from nova.objects import fields
class InstanceMapping(base.NovaTimestampObject, base.NovaObject):
# Version 1.0: Initial version
VERSION = '1.0'
fields = {
'id': fields.IntegerField(read_only=True),
'instance_uuid': fields.UUIDField(),
'cell_id': fields.IntegerField(),
'project_id': fields.StringField(),
}
@staticmethod
def _from_db_object(context, instance_mapping, db_instance_mapping):
for key in instance_mapping.fields:
setattr(instance_mapping, key, db_instance_mapping[key])
instance_mapping.obj_reset_changes()
instance_mapping._context = context
return instance_mapping
@staticmethod
def _get_by_instance_uuid_from_db(context, instance_uuid):
session = db_api.get_api_session()
with session.begin():
db_mapping = session.query(
api_models.InstanceMapping).filter_by(
instance_uuid=instance_uuid).first()
if not db_mapping:
raise exception.InstanceMappingNotFound(uuid=instance_uuid)
return db_mapping
@base.remotable_classmethod
def get_by_instance_uuid(cls, context, instance_uuid):
db_mapping = cls._get_by_instance_uuid_from_db(context, instance_uuid)
return cls._from_db_object(context, cls(), db_mapping)
@staticmethod
def _create_in_db(context, updates):
session = db_api.get_api_session()
db_mapping = api_models.InstanceMapping()
db_mapping.update(updates)
db_mapping.save(session)
return db_mapping
@base.remotable
def create(self):
db_mapping = self._create_in_db(self._context, self.obj_get_changes())
self._from_db_object(self._context, self, db_mapping)
@staticmethod
def _save_in_db(context, instance_uuid, updates):
session = db_api.get_api_session()
with session.begin():
db_mapping = session.query(
api_models.InstanceMapping).filter_by(
instance_uuid=instance_uuid).first()
if not db_mapping:
raise exception.InstanceMappingNotFound(uuid=instance_uuid)
db_mapping.update(updates)
session.add(db_mapping)
return db_mapping
@base.remotable
def save(self):
changes = self.obj_get_changes()
db_mapping = self._save_in_db(self._context, self.instance_uuid,
changes)
self._from_db_object(self._context, self, db_mapping)
self.obj_reset_changes()
@staticmethod
def _destroy_in_db(context, instance_uuid):
session = db_api.get_api_session()
with session.begin():
result = session.query(api_models.InstanceMapping).filter_by(
instance_uuid=instance_uuid).delete()
if not result:
raise exception.InstanceMappingNotFound(uuid=instance_uuid)
@base.remotable
def destroy(self):
self._destroy_in_db(self._context, self.instance_uuid)
class InstanceMappingList(base.ObjectListBase, base.NovaObject):
# Version 1.0: Initial version
VERSION = '1.0'
fields = {
'objects': fields.ListOfObjectsField('InstanceMapping'),
}
child_versions = {
'1.0': '1.0',
}
@staticmethod
def _get_by_project_id_from_db(context, project_id):
session = db_api.get_api_session()
with session.begin():
db_mappings = session.query(api_models.InstanceMapping).filter_by(
project_id=project_id).all()
return db_mappings
@base.remotable_classmethod
def get_by_project_id(cls, context, project_id):
db_mappings = cls._get_by_project_id_from_db(context, project_id)
return base.obj_make_list(context, cls(), objects.InstanceMapping,
db_mappings)