在Ruby中执行javascript代码

Question

只需要执行以下javascript并获取变量值。

var u = http://track.fk;
var u2 = g.tv/2grc4?track=pub3878f5a9bae34c50a9f3ab0b59e1022e&pubid=8afa71db&aff_sub=pub3878f5a9bae34c50a9f3ab0b59e1022e;
var link = document.getElementById(click);
setTimeout(function() { link.href = u+u2; }, 333);
setTimeout(function() {
    var meta = document.createElement('meta');
    meta.httpEquiv = 'refresh';
    meta.content = '1;'+u+u2;
    document.getElementsByTagName('head')[0].appendChild(meta);
    window.location.href = u+u2;
    window.location.replace(u+u2);
}, 333);

我尝试过使用gem

gem "therubyracer"

但我收到错误

V8::Error: Unexpected token : at <eval>:1:14

预期产出，

u = http://track.fk, u2 = g.tv/2grc4... and other values in ruby