[Zope] disable page cacheing

Sam Gendler sgendler@teknolojix.com
Fri, 03 Dec 1999 12:38:13 -0800


I am fairly new to zope myself, but my first thought would be to make a ZClass
that inherits from image and then somehow convince zope to send Cache-Control:
no-cache headers whenever it serves an object of that type.

The real question would be, why do you want to disable browser caching of
images.  Browsing an uncacheable website over a modem is a nightmare.  Every
time you hit the back button or put your mouse on a rollover, you have to wait
for a new download.  If it is just for development purposes, turn your cache off
in netscape by setting the size of the caches to 0.  In IE, You have to be
sneakier.  Make an exceedingly small disk partition (say 5-10KB), and then tell
IE to put its Temporary Internet Files in that partition.  Since IE insists on
using at least 1% of the disk, you have to give it a VERY small disk.

Hitting shift when you hit the reload button should send Cache-Control: no-cache
instead of an If-Modified-Since header.  However, the early versions of IE 5.0
disabled that feature so that microsoft could break all of the caching products
that were released that were competing with MS Proxy.  I have no idea if they
have re-established the correct behaviour, but it is worth the test.

-sam

Geir B Hansen wrote:

> > Forget my previous message.  You actually want to use
> > RESPONSE.appendHeader('Cache-Control', 'no-cache'), since that will
> apend the
> > header to the end of a comma delimited list of any previously set
> Cache-Control
> > headers.
> >
> > --sam
> >
>
> Is there any way i can append this header information to images served
> ??
> Browser caching of images is causing me a great deal of trouble, and i
> presently resort to the ?timestamp-hack , which is not by any means
> ideal..
>
> ------------------------------------------------
> Geir B Hansen
> geirh@funcom.com
> Web-designer / Graphic artist
> Funcom Oslo
> http://www.funcom.com
> ------------------------------------------------