flask_utils.py 文件源码

def _load_from_config_dict(self, config_dict):
        try:
            name = config_dict.pop('name')
            engine = config_dict.pop('engine')
        except KeyError:
            raise RuntimeError('DATABASE configuration must specify a '
                               '`name` and `engine`.')

        if '.' in engine:
            path, class_name = engine.rsplit('.', 1)
        else:
            path, class_name = 'peewee', engine

        try:
            __import__(path)
            module = sys.modules[path]
            database_class = getattr(module, class_name)
            assert issubclass(database_class, _Database)
        except ImportError:
            raise RuntimeError('Unable to import %s' % engine)
        except AttributeError:
            raise RuntimeError('Database engine not found %s' % engine)
        except AssertionError:
            raise RuntimeError('Database engine not a subclass of '
                               'peewee.Database: %s' % engine)

        return database_class(name, **config_dict)