cyborg/cyborg/db/sqlalchemy/api.py

115 lines
3.3 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.
"""SQLAlchemy storage backend."""
import threading
from oslo_db import exception as db_exc
from oslo_db.sqlalchemy import enginefacade
from oslo_db.sqlalchemy import utils as sqlalchemyutils
from oslo_log import log
from oslo_utils import strutils
from oslo_utils import uuidutils
from cyborg.common import exception
from cyborg.db import api
from cyborg.db.sqlalchemy import models
_CONTEXT = threading.local()
LOG = log.getLogger(__name__)
def get_backend():
"""The backend is this module itself."""
return Connection()
def _session_for_read():
return enginefacade.reader.using(_CONTEXT)
def _session_for_write():
return enginefacade.writer.using(_CONTEXT)
def model_query(context, model, *args, **kwargs):
"""Query helper for simpler session usage.
:param context: Context of the query
:param model: Model to query. Must be a subclass of ModelBase.
:param args: Arguments to query. If None - model is used.
Keyword arguments:
:keyword project_only:
If set to True, then will do query filter with context's project_id.
if set to False or absent, then will not do query filter with context's
project_id.
:type project_only: bool
"""
if kwargs.pop("project_only", False):
kwargs["project_id"] = context.tenant
with _session_for_read() as session:
query = sqlalchemyutils.model_query(
model, session, args, **kwargs)
return query
def add_identity_filter(query, value):
"""Adds an identity filter to a query.
Filters results by ID, if supplied value is a valid integer.
Otherwise attempts to filter results by UUID.
:param query: Initial query to add filter to.
:param value: Value for filtering results by.
:return: Modified query.
"""
if strutils.is_int_like(value):
return query.filter_by(id=value)
elif uuidutils.is_uuid_like(value):
return query.filter_by(uuid=value)
else:
raise exception.InvalidIdentity(identity=value)
class Connection(api.Connection):
"""SqlAlchemy connection."""
def __init__(self):
pass
def accelerator_create(self, context, values):
if not values.get('uuid'):
values['uuid'] = uuidutils.generate_uuid()
if not values.get('description'):
values['description'] = ''
accelerator = models.Accelerator()
accelerator.update(values)
with _session_for_write() as session:
try:
session.add(accelerator)
session.flush()
except db_exc.DBDuplicateEntry:
raise exception.AcceleratorAlreadyExists(uuid=values['uuid'])
return accelerator