Re: default cache_stoplist question

> The problem is that GETs aren't guaranteed to be idempotent...
...
> Similarly, things like imagemaps just couldn't be done with POST (at
> least not with the current browser standards), and although indeed in
> most cases, the result of clicking on an image _could_ be cached, it
> would be a) pointless, because if someone clicked on the same icon,
> but one pixel away it wouldn't know to use the cached copy, and b)
> its difficult to tell between when the output should and should not
> be cached.

The server knows when it should be cached, all imagemaps (etc) which result in
the same object could result in a redirect to that object. Ok, the redirect
isn't cached but the resulting object is.

> squid doesn't cache cgi-bin and ? because these are the most common
> methods of showing that something is a dynamically-generated page in
> the URL. Other methods using HTTP headers exist, but are more
> difficult to use, and aren't portable between different brands of web
> server, so users tend not to use them.

dynamically-generated does not imply uncacheable. For those pages which
shouldn't be cached the script ought to insert headers to mark them as such.

I've turned off the cgi-big, and ? entries in our Squid, and I'll see if I get
lots of complaints. Personally I think that there will be few problems.

 -- Jon
Received on Thu Oct 16 1997 - 22:59:20 MDT