Sean Mooney
00d08a3288
- This change tries to address an edge case discovered when running placement under mod_wsgi where if the placement wsgi application is re-initialize the db_api configure method attempts to reconfigure a started transaction factory. - This since oslo.db transaction factories do not support reconfiguration at runtime this result in an exception being raised preventing reloading of the Placement API without restarting apache to force mod_wsgi to recreate the python interpreter. - This change introduces a run once decorator to allow annotating functions that should only be executed once for the lifetime fo an interpreter. - This change applies the run_once decorator to the db_api configure method, to suppress the attempt to reconfigure the current TransactionFactory on application reload. Co-Authored-By: Balazs Gibizer <balazs.gibizer@ericsson.com> Closes-Bug: #1799246 Related-Bug: #1784155 Change-Id: I704196711d30c1124e713ac31111a8ea6fa2f1ba
49 lines
1.7 KiB
Python
49 lines
1.7 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.
|
|
"""Database context manager for placement database connection, kept in its
|
|
own file so the nova db_api (which has cascading imports) is not imported.
|
|
"""
|
|
|
|
from oslo_db.sqlalchemy import enginefacade
|
|
from oslo_log import log as logging
|
|
|
|
from nova.utils import run_once
|
|
|
|
placement_context_manager = enginefacade.transaction_context()
|
|
LOG = logging.getLogger(__name__)
|
|
|
|
|
|
def _get_db_conf(conf_group):
|
|
return dict(conf_group.items())
|
|
|
|
|
|
@run_once("TransactionFactory already started, not reconfiguring.",
|
|
LOG.warning)
|
|
def configure(conf):
|
|
# If [placement_database]/connection is not set in conf, then placement
|
|
# data will be stored in the nova_api database.
|
|
if conf.placement_database.connection is None:
|
|
placement_context_manager.configure(
|
|
**_get_db_conf(conf.api_database))
|
|
else:
|
|
placement_context_manager.configure(
|
|
**_get_db_conf(conf.placement_database))
|
|
|
|
|
|
def get_placement_engine():
|
|
return placement_context_manager.writer.get_engine()
|
|
|
|
|
|
@enginefacade.transaction_context_provider
|
|
class DbContext(object):
|
|
"""Stub class for db session handling outside of web requests."""
|