neutron-lbaas/neutron/db/migration/alembic_migrations/env.py
Jakub Libosvar de403598f6 add engine parameter for offline migrations
Offline migration required config file containing connection string.
In that case only engine from URL was used. With this patch engine can be
passed from command line (or config file) along with plugins which sql
script will be generated accordingly.

DocImpact

Change-Id: Ib667a71960b833fd981f97fe7d6b1856084ef5c8
Closes-Bug: #1304326
2014-06-03 14:19:09 +02:00

107 lines
3.0 KiB
Python

# Copyright 2012 New Dream Network, LLC (DreamHost)
#
# 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.
#
# @author: Mark McClain, DreamHost
from logging import config as logging_config
from alembic import context
from sqlalchemy import create_engine, pool
from neutron.db import model_base
from neutron.openstack.common import importutils
DATABASE_QUOTA_DRIVER = 'neutron.extensions._quotav2_driver.DbQuotaDriver'
# this is the Alembic Config object, which provides
# access to the values within the .ini file in use.
config = context.config
neutron_config = config.neutron_config
# Interpret the config file for Python logging.
# This line sets up loggers basically.
logging_config.fileConfig(config.config_file_name)
plugin_class_path = neutron_config.core_plugin
active_plugins = [plugin_class_path]
active_plugins += neutron_config.service_plugins
for class_path in active_plugins:
importutils.import_class(class_path)
# set the target for 'autogenerate' support
target_metadata = model_base.BASEV2.metadata
def run_migrations_offline():
"""Run migrations in 'offline' mode.
This configures the context with either a URL
or an Engine.
Calls to context.execute() here emit the given string to the
script output.
"""
kwargs = dict()
if neutron_config.database.connection:
kwargs['url'] = neutron_config.database.connection
else:
kwargs['dialect_name'] = neutron_config.database.engine
context.configure(**kwargs)
with context.begin_transaction():
context.run_migrations(active_plugins=active_plugins,
options=build_options())
def run_migrations_online():
"""Run migrations in 'online' mode.
In this scenario we need to create an Engine
and associate a connection with the context.
"""
engine = create_engine(
neutron_config.database.connection,
poolclass=pool.NullPool)
connection = engine.connect()
context.configure(
connection=connection,
target_metadata=target_metadata
)
try:
with context.begin_transaction():
context.run_migrations(active_plugins=active_plugins,
options=build_options())
finally:
connection.close()
def build_options():
return {'folsom_quota_db_enabled': is_db_quota_enabled()}
def is_db_quota_enabled():
return neutron_config.QUOTAS.quota_driver == DATABASE_QUOTA_DRIVER
if context.is_offline_mode():
run_migrations_offline()
else:
run_migrations_online()