def construct_request_uri(local_dir, base_path, **kwargs):
    """
    Constructs a special redirect_uri to be used when communicating with
    one OP. Each OP should get their own redirect_uris.
    
    :param local_dir: Local directory in which to place the file
    :param base_path: Base URL to start with
    :param kwargs: 
    :return: 2-tuple with (filename, url) 
    """
    _filedir = local_dir
    if not os.path.isdir(_filedir):
        os.makedirs(_filedir)
    _webpath = base_path
    _name = rndstr(10) + ".jwt"
    filename = os.path.join(_filedir, _name)
    while os.path.exists(filename):
        _name = rndstr(10)
        filename = os.path.join(_filedir, _name)
    _webname = "%s%s" % (_webpath, _name)
    return filename, _webname