On Thu, Jul 3, 2008 at 3:34 PM, Julian Reschke <[EMAIL PROTECTED]> wrote: > Marcos Caceres wrote: >> >> On Wed, Jul 2, 2008 at 10:17 PM, mike amundsen <[EMAIL PROTECTED]> wrote: >>> >>> Marcos: >>> >>> <snip> >>>> >>>> I'm sure it could be done. But how can this be done easily with Apache >>>> or IIS? >>> >>> </snip> >>> >>> Since Apache and IIS are HTTP servers, you can use the HTTP Headers to >>> send hash data. Using the ETag is the most common, but if you like, >>> you can propose a new HTTP Header ("X-Widget-Hash"). >> >> I know I should be able to do to send HTTP headers, but the question >> is still *how*? I mean, for Apache, do I modify the .htaccess file? if >> so, what do I put in there? If I can get a web server to send a custom >> ETag or Widget-Hash easily enough, then the solution is doable so long >> as its also easy to replicate in IIS and on any other web server. > > *Sending* a custom etag is not sufficient; Apache needs to be aware of it, > otherwise all the conditional HTTP stuff will stop working.
Yeah, this is kinda what I'm getting at :) >> FWIW, if it comes down to having to introduce a custom HTTP header, >> then I definitely think we should dump this solution. > > What about Content-MD5? Not supported by IIS, AFAIK. In Apache, sure, but, as [1] states, "Note that this can cause performance problems on your server since the message digest is computed on every request (the values are not cached)." And [2] says "It was a bit proof-of-content code I added to Apache, and was never designed to be used in a real web server...." [1] http://apache.active-venture.com/mod/core3.htm [2] http://mail-archives.apache.org/mod_mbox/httpd-dev/199708.mbox/[EMAIL PROTECTED] -- Marcos Caceres http://datadriven.com.au