216_havana.py 文件源码

def _create_shadow_tables(migrate_engine):
    meta = MetaData(migrate_engine)
    meta.reflect(migrate_engine)
    table_names = list(meta.tables.keys())

    meta.bind = migrate_engine

    for table_name in table_names:
        table = Table(table_name, meta, autoload=True)

        columns = []
        for column in table.columns:
            column_copy = None
            # NOTE(boris-42): BigInteger is not supported by sqlite, so
            #                 after copy it will have NullType, other
            #                 types that are used in Nova are supported by
            #                 sqlite.
            if isinstance(column.type, NullType):
                column_copy = Column(column.name, BigInteger(), default=0)
            if table_name == 'instances' and column.name == 'locked_by':
                enum = Enum('owner', 'admin',
                            name='shadow_instances0locked_by')
                column_copy = Column(column.name, enum)
            else:
                column_copy = column.copy()
            columns.append(column_copy)

        shadow_table_name = 'shadow_' + table_name
        shadow_table = Table(shadow_table_name, meta, *columns,
                             mysql_engine='InnoDB')
        try:
            shadow_table.create()
        except Exception:
            LOG.info(repr(shadow_table))
            LOG.exception(_LE('Exception while creating table.'))
            raise