Unify using of migration tools

Currently magnum has two type of migration tools, one is oslo.db
migration_cli, other is calling alembic migration tool directly.
This fixes to get more consistency.

Closes-Bug: #1487248
Change-Id: I705dd2cc65c1f879ce1e2ebaaf2015dc6dc24c64

magnum/cmd/db_manage.py

@@ -13,35 +13,31 @@
 
 """Starter script for magnum-db-manage."""
 
-import os
-
 from oslo_config import cfg
-from oslo_db import options
-from oslo_db.sqlalchemy.migration_cli import manager
 from oslo_log import log as logging
 
-from magnum.i18n import _
+from magnum.db import migration
 
 
 LOG = logging.getLogger(__name__)
 CONF = cfg.CONF
 
 
-def do_version(mgr):
-    print('Current DB revision is %s' % mgr.version())
+def do_version():
+    print('Current DB revision is %s' % migration.version())
 
 
-def do_upgrade(mgr):
-    mgr.upgrade(CONF.command.revision)
+def do_upgrade():
+    migration.upgrade(CONF.command.revision)
 
 
-def do_stamp(mgr):
-    mgr.stamp(CONF.command.revision)
+def do_stamp():
+    migration.stamp(CONF.command.revision)
 
 
-def do_revision(mgr):
-    mgr.revision(message=CONF.command.message,
-                 autogenerate=CONF.command.autogenerate)
+def do_revision():
+    migration.revision(message=CONF.command.message,
+                       autogenerate=CONF.command.autogenerate)
 
 
 def add_command_parsers(subparsers):
@@ -62,23 +58,6 @@ def add_command_parsers(subparsers):
     parser.set_defaults(func=do_revision)
 
 
-def get_manager():
-    if cfg.CONF.database.connection is None:
-        raise ValueError(
-            _('Could not find parameter database.connection in config file'))
-
-    alembic_path = os.path.abspath(
-        os.path.join(os.path.dirname(__file__),
-                     '..', 'db', 'sqlalchemy', 'alembic.ini'))
-    migrate_path = os.path.abspath(
-        os.path.join(os.path.dirname(__file__),
-                     '..', 'db', 'sqlalchemy', 'alembic'))
-    migration_config = {'alembic_ini_path': alembic_path,
-                        'alembic_repo_path': migrate_path,
-                        'db_url': CONF.database.connection}
-    return manager.MigrationManager(migration_config)
-
-
 def main():
     command_opt = cfg.SubCommandOpt('command',
                                     title='Command',
@@ -86,8 +65,5 @@ def main():
                                     handler=add_command_parsers)
     CONF.register_cli_opt(command_opt)
 
-    # set_defaults() is called to register the db options.
-    options.set_defaults(CONF)
-
     CONF(project='magnum')
-    CONF.command.func(get_manager())
+    CONF.command.func()

magnum/db/__init__.py

@@ -0,0 +1,31 @@
+# Copyright 2015 NEC Corporation.  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.
+
+from oslo_config import cfg
+from oslo_db import options
+
+from magnum.common import paths
+
+
+sql_opts = [
+    cfg.StrOpt('mysql_engine',
+               default='InnoDB',
+               help='MySQL engine to use.')
+]
+
+_DEFAULT_SQL_CONNECTION = 'sqlite:///' + paths.state_path_def('magnum.sqlite')
+
+
+cfg.CONF.register_opts(sql_opts, 'database')
+options.set_defaults(cfg.CONF, _DEFAULT_SQL_CONNECTION, 'magnum.sqlite')

magnum/db/migration.py

@@ -46,7 +46,3 @@ def stamp(version):
 
 def revision(message, autogenerate):
     return get_backend().revision(message, autogenerate)
-
-
-def create_schema():
-    return get_backend().create_schema()

magnum/db/sqlalchemy/migration.py

@@ -16,77 +16,48 @@
 
 import os
 
-import alembic
-from alembic import config as alembic_config
-import alembic.migration as alembic_migration
-from oslo_db import exception as db_exc
+from oslo_config import cfg
+from oslo_db.sqlalchemy.migration_cli import manager
 
-from magnum.db.sqlalchemy import api as sqla_api
-from magnum.db.sqlalchemy import models
+_MANAGER = None
 
 
-def _alembic_config():
-    path = os.path.join(os.path.dirname(__file__), 'alembic.ini')
-    config = alembic_config.Config(path)
-    return config
+def get_manager():
+    global _MANAGER
+    if not _MANAGER:
+        alembic_path = os.path.abspath(
+            os.path.join(os.path.dirname(__file__), 'alembic.ini'))
+        migrate_path = os.path.abspath(
+            os.path.join(os.path.dirname(__file__), 'alembic'))
+        migration_config = {'alembic_ini_path': alembic_path,
+                            'alembic_repo_path': migrate_path,
+                            'db_url': cfg.CONF.database.connection}
+        _MANAGER = manager.MigrationManager(migration_config)
+
+    return _MANAGER
 
 
-def version(config=None, engine=None):
+def version():
     """Current database version.
 
     :returns: Database version
     :rtype: string
     """
-    if engine is None:
-        engine = sqla_api.get_engine()
-    with engine.connect() as conn:
-        context = alembic_migration.MigrationContext.configure(conn)
-        return context.get_current_revision()
+    return get_manager().version()
 
 
-def upgrade(revision, config=None):
+def upgrade(version):
     """Used for upgrading database.
 
     :param version: Desired database version
     :type version: string
     """
-    revision = revision or 'head'
-    config = config or _alembic_config()
+    version = version or 'head'
 
-    alembic.command.upgrade(config, revision or 'head')
+    get_manager().upgrade(version)
 
 
-def create_schema(config=None, engine=None):
-    """Create database schema from models description.
-
-    Can be used for initial installation instead of upgrade('head').
-    """
-    if engine is None:
-        engine = sqla_api.get_engine()
-
-    # NOTE(viktors): If we will use metadata.create_all() for non empty db
-    #                schema, it will only add the new tables, but leave
-    #                existing as is. So we should avoid of this situation.
-    if version(engine=engine) is not None:
-        raise db_exc.DbMigrationError("DB schema is already under version"
-                                      " control. Use upgrade() instead")
-
-    models.Base.metadata.create_all(engine)
-    stamp('head', config=config)
-
-
-def downgrade(revision, config=None):
-    """Used for downgrading database.
-
-    :param version: Desired database version
-    :type version: string
-    """
-    revision = revision or 'base'
-    config = config or _alembic_config()
-    return alembic.command.downgrade(config, revision)
-
-
-def stamp(revision, config=None):
+def stamp(revision):
     """Stamps database with provided revision.
 
     Don't run any migrations.
@@ -95,11 +66,10 @@ def stamp(revision, config=None):
                      database with most recent revision
     :type revision: string
     """
-    config = config or _alembic_config()
-    return alembic.command.stamp(config, revision=revision)
+    get_manager().stamp(revision)
 
 
-def revision(message=None, autogenerate=False, config=None):
+def revision(message=None, autogenerate=False):
     """Creates template for migration.
 
     :param message: Text that will be used for migration title
@@ -108,6 +78,4 @@ def revision(message=None, autogenerate=False, config=None):
                          state
     :type autogenerate: bool
     """
-    config = config or _alembic_config()
-    return alembic.command.revision(config, message=message,
-                                    autogenerate=autogenerate)
+    return get_manager().revision(message=message, autogenerate=autogenerate)

magnum/db/sqlalchemy/models.py

@@ -19,7 +19,6 @@ SQLAlchemy models for container service
 import json
 
 from oslo_config import cfg
-from oslo_db import options as db_options
 from oslo_db.sqlalchemy import models
 import six.moves.urllib.parse as urlparse
 from sqlalchemy import Column
@@ -30,21 +29,6 @@ from sqlalchemy import String
 from sqlalchemy import Text
 from sqlalchemy.types import TypeDecorator, TEXT
 
-from magnum.common import paths
-
-
-sql_opts = [
-    cfg.StrOpt('mysql_engine',
-               default='InnoDB',
-               help='MySQL engine to use.')
-]
-
-_DEFAULT_SQL_CONNECTION = 'sqlite:///' + paths.state_path_def('magnum.sqlite')
-
-
-cfg.CONF.register_opts(sql_opts, 'database')
-db_options.set_defaults(cfg.CONF, _DEFAULT_SQL_CONNECTION, 'magnum.sqlite')
-
 
 def table_args():
     engine_name = urlparse.urlparse(cfg.CONF.database.connection).scheme

setup.cfg

@@ -59,5 +59,8 @@ magnum.template_definitions =
     magnum_vm_atomic_swarm = magnum.conductor.template_definition:AtomicSwarmTemplateDefinition
     magnum_vm_ubuntu_mesos = magnum.conductor.template_definition:UbuntuMesosTemplateDefinition
 
+magnum.database.migration_backend =
+    sqlalchemy = magnum.db.sqlalchemy.migration
+
 [wheel]
 universal = 1