helpers.py 文件源码

def get_or_404(model: t.Type[Y], object_id: t.Any) -> Y:
    """Get the specified object by primary key or raise an exception.

    .. note::
        ``Y`` is bound to :py:class:`psef.models.Base`, so it should be a
        SQLAlchemy model.

    :param model: The object to get.
    :param object_id: The primary key identifier for the given object.
    :returns: The requested object.

    :raises APIException: If no object with the given id could be found.
        (OBJECT_ID_NOT_FOUND)
    """
    obj: t.Optional[Y] = model.query.get(object_id)
    if obj is None:
        raise psef.errors.APIException(
            f'The requested "{model.__name__}" was not found',
            f'There is no "{model.__name__}" with primary key {object_id}',
            psef.errors.APICodes.OBJECT_ID_NOT_FOUND, 404
        )
    return obj