我想知道为什么 Cloulflare 不会缓存某个静态 js 文件。
鉴于要求：
curl -I http://www.testlifeinuk.com/dist/lifeinuk.js
标题返回如下：
HTTP/1.1 200 OK
Date: Mon, 12 Jan 2015 10:59:21 GMT
Content-Type: application/javascript
Connection: keep-alive
Set-Cookie: __cfduid=d11a9f01292153436a211a9d807a3399b1421060361; expires=Tue, 12-Jan-16 10:59:21 GMT; path=/; domain=.testlifeinuk.com; HttpOnly
X-Powered-By: Express
Etag: W/"507660-1420797981000"
Cache-Control: public, max-age=1382400
Last-Modified: Fri, 09 Jan 2015 10:06:21 GMT
Vary: Accept-Encoding
Via: 1.1 vegur
CF-Cache-Status: MISS
Expires: Wed, 28 Jan 2015 10:59:21 GMT
Server: cloudflare-nginx
CF-RAY: 1a78d818b4af0b81-LHR
令我困惑的是，无论我做了多少次请求，它总是返回
CF-Cache-Status: MISS
知道为什么吗？