On Thu, 28 Oct 1999 10:09:38 +1000, Garth T Kidd wrote:

Why zpowered.jpg is cacheable but none of the others are is beyond me. Whatever's going on, though, we should fix it. There's no reason those guys can't be sending an accurate Last-modified and a reasonable Expires (say, an hour or a day in the future -- how often are you going to change 'em?).

I'd like to help in whatever way I can. I can say that there are currently no 'Expires' headers anywhere in the Zope source and that Zope has a (reported 2-days ago) bug that it's IF-MODIFIED-SINCE HTTP header conditional in OFS/Images.py is *backward*, resulting in odd updating of images. I'm also seeing occasional CONTENT-LENGTHs of zero, and then Zope shoves out an GIF image anyway, choking some browsers. I'm still trying to nail this one down before reporting futher. I may be doing something wrong in my objects.

The goal is simple: figure out what modifications can be made to Zope's basic items so that they're at least reasonably cacheable. The best reference for figuring out what headers we want to generate is probably Mark's Caching Tutorial for Web Authors and Webmasters:

http://www.mnot.net/cache_docs/

I'm off to read it so we can talk. I need to learn more re caching anyway to fix my dynamic image update problem. -Jeff Rush