firefox - Forcing cache expiration from a JavaScript file

Question

I have an old version of a JS file cached on users' browsers, with expiration set to 10 years (since then, I have learned how to set expires headers correctly on my web server). I have made updates to the JS file, and I want my users to benefit from them.

• Is there any way my web server can force users' browsers to clear the cache for this one file, short of serving a differently named JS file?
• In the future, if expires headers are not set correctly (paranoia), can my JS file automatically expire itself and force a reload after, say, a day has passed since it was cached?

EDIT: Ideally I want to solve this problem without changing HTML markup on the page that hosts the script.

Answer 1

In short... no.

You can add something to the end of the source address of the script tag. Browsers will treat this as a different file to the one they have currently cached.

<script src="/js/something.js?version=2"></script>

Not sure about your other options.