[Zope] Browser Sticky Fingers

[Anthony Baxter]

>>> "Jeff Rush" wrote
> I'm pulling my hair out here over what is probably a simple HTTP issue.
> I have a Zope method that stuffs a new image into a Zope Image object,
> based on the content of the page where the method is called.
> 
> The problem is that the image is not updated until I exit the browser,
> and then flush all of it's caches manually.
> 
> I've turned off any proxy support, configured Netscape 4.x with the
[...]

> Am I missing something simple?

Yep. Browsers suck. They cache images regardless. The disgusting 
hack is to always call your image with the current time in the URL -
eg. <img src="/your/image/method?dummy_ts=<dtml-var "ZopeTime().timeTime()">">
/your/image/method should feel entirely free to ignore dummy_ts.

This way the image has a different URL, and so the browser doesn't
use a cached one.

When you're producing on-the-fly live statistics as a graph, this 
hideous misfeature is a complete pain in the clacker.

Anthony
-- 
Anthony Baxter     <anthony@interlink.com.au>   
It's never too late to have a happy childhood.