def aio_rpc_notification(method):
    """
    A method decorator announcing the method to be exposed as
    a notification handler.

    This decorator assumes that the first parameter (after ``self``)
    takes a BSONRpc/JSONRpc object reference as an argument.
    From the second parameter onward the
    parameters are exposed as-is to the peer node.
    """
    method._notification_handler = True
    return method
