Example #1
0
def version(config=None, engine=None):
    """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()
Example #2
0
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 = sqla_api.get_engine()
    with engine.connect() as connection:
        context.configure(connection=connection,
                          target_metadata=target_metadata)
        with context.begin_transaction():
            context.run_migrations()
Example #3
0
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)