Why would the browser cache assets (images, js, etc.) while GETting but re-request everything after a POST + 302 redirect?

Question

We've got our ETags and expiry headers setup properly and when browsing around the site without posting it is really very snappy. However, after any POST (which is almost invariably followed with a 302) you can see the browser re-request all the images. Is there something that could be causing this? Is there a setting that handles this?

Answer 1

I believe typically you still get a request but with 'If-Modified-Since' in the header -- at least that's what I've observed, even with expires headers. The response should be 304 (not modified) which is ultraquick. Or are you saying all the images are reloaded entirely?

Read more on If-Modified Since Read about If-Modified-Since in HTTP RFC