nova/nova/db/migration.py

109 lines
3.8 KiB
Python

# 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.
import os
from alembic import command as alembic_api
from alembic import config as alembic_config
from alembic.runtime import migration as alembic_migration
from oslo_log import log as logging
from nova.db.api import api as api_db_api
from nova.db.main import api as main_db_api
from nova import exception
LOG = logging.getLogger(__name__)
def _get_engine(database='main', context=None):
if database == 'main':
return main_db_api.get_engine(context=context)
if database == 'api':
return api_db_api.get_engine()
def _find_alembic_conf(database='main'):
"""Get the path for the alembic repository."""
path = os.path.join(
os.path.abspath(os.path.dirname(__file__)),
database, 'alembic.ini')
config = alembic_config.Config(path)
# we don't want to use the logger configuration from the file, which is
# only really intended for the CLI
# https://stackoverflow.com/a/42691781/613428
config.attributes['configure_logger'] = False
return config
def _upgrade_alembic(engine, config, version):
# reuse the connection rather than creating a new one
with engine.begin() as connection:
config.attributes['connection'] = connection
alembic_api.upgrade(config, version or 'head')
def db_sync(version=None, database='main', context=None):
"""Migrate the database to `version` or the most recent version."""
if database not in ('main', 'api'):
raise exception.Invalid('%s is not a valid database' % database)
# if the user requested a specific version, check if it's an integer:
# if so, we're almost certainly in sqlalchemy-migrate land and won't
# support that
if version is not None and version.isdigit():
raise exception.Invalid(
'You requested an sqlalchemy-migrate database version; this is '
'no longer supported'
)
engine = _get_engine(database, context=context)
config = _find_alembic_conf(database)
# discard the URL stored in alembic.ini in favour of the URL configured
# for the engine, casting from 'sqlalchemy.engine.url.URL' to str in the
# process
# NOTE(sean-k-mooney): the engine has already url encoded the connection
# string using a mix of url encode styles for different parts of the url.
# since we are updating the alembic config parser instance we need to
# escape '%' to '%%' to account for ConfigParser's string interpolation.
url = engine.url.render_as_string(hide_password=False).replace('%', '%%')
config.set_main_option('sqlalchemy.url', url)
# apply anything later
LOG.info('Applying migration(s)')
_upgrade_alembic(engine, config, version)
LOG.info('Migration(s) applied')
def db_version(database='main', context=None):
"""Display the current database version."""
if database not in ('main', 'api'):
raise exception.Invalid('%s is not a valid database' % database)
engine = _get_engine(database, context=context)
with engine.connect() as conn:
m_context = alembic_migration.MigrationContext.configure(conn)
version = m_context.get_current_revision()
return version