samaxes / javaee-cache-filter Goto Github PK

Chrome page speed suggests using this header to avoid issues with public proxies that do not detect the presence of a Content-Encoding header properly. See https://developers.google.com/speed/docs/best-practices/caching#LeverageProxyCaching

Any reason the "Pragma: no-cache" header is not included in the NoCacheFilter?

With this in web.xml

<init-param>
    <param-name>expirationTime</param-name>
    <param-value>14400</param-value>
</init-param>

When fetching a resource at 2014-10-16 14:39:40 in GMT +2 (with daylight savings active, +1 normally) This is in Sweden.

HTTP/1.1 200 OK
Cache-Control: public, max-age=14400
Date: Thu, 16 Oct 2014 12:39:40 GMT
Content-Length: 82718
Content-Type: text/css
Expires: Thu, 16 Oct 2014 16:39:40 GMT
Last-Modified: Thu, 16 Oct 2014 11:55:58 GMT
X-Powered-By: Servlet/2.5 JSP/2.1

In init of CacheFilter the time difference to GMT should be observed and accounted for.

seconds = Long.valueOf(filterConfig.getInitParameter(CacheConfigParameter.EXPIRATION_TIME.getName()));

This is off-course only interesting when using short cache times, if we cache it for 6 months the few hours means nothing obviously.

Regarding the NoCache filter. It sets both no-cache and no-store. But I was looking for a solution that only sets no-cache. So I can still benefit from a revalidation using Etags. See e.g. this article on developers.google which explains the principles excellently.

So I propose making no-store optional. I'll make a pull request.

By the way, I think no-store obsoletes no-cache, since it would not allow storing anything at all to begin with. But I suppose it does no harm to have both.