[Zope] Zope Cacheability

[Jeff Rush]

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