trove/reddwarf/db/__init__.py
Russell Bryant 1aaed59b4b s/OpenStack LLC/OpenStack Foundation/ in Copyright.
Update Copyright statements that previously said 'OpenStack LLC' to now
say 'OpenStack Foundation'.  Note that the files under openstack/common/
were not updated, as those changes should be brought in by syncing with
oslo-incubator.

Change-Id: I22db9858e899cff72053a4b48100fcc039f5d9dd
2013-04-29 18:33:42 -04:00

111 lines
3.3 KiB
Python

# vim: tabstop=4 shiftwidth=4 softtabstop=4
# Copyright 2010-2011 OpenStack Foundation
# 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.
import optparse
from reddwarf.common import utils
from reddwarf.common import cfg
CONF = cfg.CONF
db_api_opt = CONF.db_api_implementation
def get_db_api():
return utils.import_module(db_api_opt)
class Query(object):
"""Mimics sqlalchemy query object.
This class allows us to store query conditions and use them with
bulk updates and deletes just like sqlalchemy query object.
Using this class makes the models independent of sqlalchemy
"""
def __init__(self, model, query_func, **conditions):
self._query_func = query_func
self._model = model
self._conditions = conditions
self.db_api = get_db_api()
def all(self):
return self.db_api.list(self._query_func, self._model,
**self._conditions)
def count(self):
return self.db_api.count(self._query_func, self._model,
**self._conditions)
def __iter__(self):
return iter(self.all())
def update(self, **values):
self.db_api.update_all(self._query_func, self._model, self._conditions,
values)
def delete(self):
self.db_api.delete_all(self._query_func, self._model,
**self._conditions)
def limit(self, limit=200, marker=None, marker_column=None):
return self.db_api.find_all_by_limit(
self._query_func,
self._model,
self._conditions,
limit=limit,
marker=marker,
marker_column=marker_column)
def paginated_collection(self, limit=200, marker=None, marker_column=None):
collection = self.limit(int(limit) + 1, marker, marker_column)
if len(collection) > int(limit):
return (collection[0:-1], collection[-2]['id'])
return (collection, None)
class Queryable(object):
def __getattr__(self, item):
return lambda model, **conditions: Query(
model, query_func=getattr(get_db_api(), item), **conditions)
db_query = Queryable()
def add_options(parser):
"""Adds any configuration options that the db layer might have.
:param parser: An optparse.OptionParser object
:retval None
"""
help_text = ("The following configuration options are specific to the "
"Reddwarf database.")
group = optparse.OptionGroup(
parser,
"Registry Database Options",
help_text)
group.add_option(
'--sql-connection',
metavar="CONNECTION",
default=None,
help="A valid SQLAlchemy connection string for the "
"registry database. Default: %default")
parser.add_option_group(group)