oslo.db/oslo/db/sqlalchemy/migration_cli/ext_alembic.py

79 lines
2.9 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.
import os
import alembic
from alembic import config as alembic_config
import alembic.migration as alembic_migration
from oslo.db.sqlalchemy.migration_cli import ext_base
from oslo.db.sqlalchemy import session as db_session
class AlembicExtension(ext_base.MigrationExtensionBase):
order = 2
@property
def enabled(self):
return os.path.exists(self.alembic_ini_path)
def __init__(self, migration_config):
"""Extension to provide alembic features.
:param migration_config: Stores specific configuration for migrations
:type migration_config: dict
"""
self.alembic_ini_path = migration_config.get('alembic_ini_path', '')
self.config = alembic_config.Config(self.alembic_ini_path)
# option should be used if script is not in default directory
repo_path = migration_config.get('alembic_repo_path')
if repo_path:
self.config.set_main_option('script_location', repo_path)
self.db_url = migration_config['db_url']
def upgrade(self, version):
return alembic.command.upgrade(self.config, version or 'head')
def downgrade(self, version):
if isinstance(version, int) or version is None or version.isdigit():
version = 'base'
return alembic.command.downgrade(self.config, version)
def version(self):
engine = db_session.create_engine(self.db_url)
with engine.connect() as conn:
context = alembic_migration.MigrationContext.configure(conn)
return context.get_current_revision()
def revision(self, message='', autogenerate=False):
"""Creates template for migration.
:param message: Text that will be used for migration title
:type message: string
:param autogenerate: If True - generates diff based on current database
state
:type autogenerate: bool
"""
return alembic.command.revision(self.config, message=message,
autogenerate=autogenerate)
def stamp(self, revision):
"""Stamps database with provided revision.
:param revision: Should match one from repository or head - to stamp
database with most recent revision
:type revision: string
"""
return alembic.command.stamp(self.config, revision=revision)