JS中通过ajax接口后台返回的文件流如何进行下载？求助

var url = "{#$apiHost#}/aw/export?brand_ids="+brand_ids;

var settings = {

  "async": true,

  "crossDomain": true,

  "url": url,

  "method": "GET",

  "headers": {"token": "{#$smarty.session.pc_token#}","os": "1"}

}

$.ajax(settings).done(function (response) {

    // console.log(response);





});