cyborg/cyborg/db/api.py

48 lines
1.3 KiB
Python

# Copyright 2017 Huawei Technologies Co.,LTD.
# 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.
"""Base classes for storage engines."""
import abc
from oslo_config import cfg
from oslo_db import api as db_api
import six
_BACKEND_MAPPING = {'sqlalchemy': 'cyborg.db.sqlalchemy.api'}
IMPL = db_api.DBAPI.from_config(cfg.CONF,
backend_mapping=_BACKEND_MAPPING,
lazy=True)
def get_instance():
"""Return a DB API instance."""
return IMPL
@six.add_metaclass(abc.ABCMeta)
class Connection(object):
"""Base class for storage system connections."""
@abc.abstractmethod
def __init__(self):
"""Constructor."""
# accelerator
@abc.abstractmethod
def accelerator_create(self, context, values):
"""Create a new server type."""