OpenStack Study: base.py

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# Copyright 2010 United States Government as represented by the

# Administrator of the National Aeronautics and Space Administration.

# 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 class for classes that need modular database access."""

from oslo.config import cfg

from nova.openstack.common import importutils

db_driver_opt = cfg.StrOpt('db_driver',

default='nova.db',

help='The driver to use for database access')

CONF = cfg.CONF

CONF.register_opt(db_driver_opt)

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class Base(object):

"""DB driver is injected in the init method."""

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    def __init__(self, db_driver=None):

        super(Base, self).__init__()

        if not db_driver:

            db_driver = CONF.db_driver

        self.db = importutils.import_module(db_driver)  # pylint: disable=C0103