Immortal objects

I had a need to fill. I've got various live graphs and charts and
whatnot produced by cgi's using META REFRESH to update periodically. All
okay so far.

Except that the browser insists on forcing reloads of the images and so
forth, which are really static content. Using reload_into_ims would
still pass something like 240 IMS requests _for_the_same_image_ up to
the next cache-layer.

Definitely not optimal.

Okay, so I wrote me a little patch. It's against version 1.1.18. It
allows the cache admin to put a magic number in maxage in a
refresh_pattern. Anything that matches that refresh_pattern is a
TCP_HIT. It cannot be reloaded, refreshed, or anything. If it's in the
cache it will be delivered from there. If the image is broken, you're
stuffed. It's broken. You have to manually purge it from the cache in
order to get any kind of refresh.

This cheerfully violates the rules of HTTP, and the semantics of
'no-cache', so should be used with _extreme_ care and in only a limited
way. But, I had a need for the behaviour, so there it is.

The 'magic' maxage is '1', unfortunately. GetInteger() is broken for
large unsigned values. I may settle in and fix that.

If people are interested, I can make a patch out of this.

D
Received on Fri Mar 27 1998 - 18:07:14 MST