Vary and Last-Modified headers about html5-boilerplate

[paulirish]

Related concern: the HTML should go out without an expires (just Last-Modified), but I was thinking about an ExpiresDefault. How can this sort of combo work?

[adeelejaz]

There are two ways I've tackled it in the past.

1. Instead of appending query at the end of the file (e.g. style.css?v=1), I append the version in the file: style-1.css Then using .htaccess I do a RewriteRule to map style-([0-9]+).css to css/style.css
2. When the resource (js or css) is fetched, I give the maximum expiry header which is 1 year. My reasoning is the css/js should be cached indefinitely and browsers don't send the HTTP request at all. If I have to replace it, I just bump the number in step 1 to: style-2.css This forces the browsers to fetch the new file.

I use the same approach on all static stuff e.g images, js, css etc

[paulirish]

Header append Vary Accept-Encoding - thx aaron peters.

closed by 9f9d6ee

[paulirish]

We can't do last-modified without a backend language, it appears.

adeel, your comments are good but we're tackling that issue via the build script.