- From: Roy T. Fielding <fielding@gbiv.com>
- Date: Mon, 8 Jun 2009 15:29:34 +0200
- To: Henrik Nordstrom <henrik@henriknordstrom.net>
- Cc: Mark Nottingham <mnot@mnot.net>, HTTP Working Group <ietf-http-wg@w3.org>
On Jun 8, 2009, at 2:57 PM, Henrik Nordstrom wrote: > mån 2009-06-08 klockan 20:57 +1000 skrev Mark Nottingham: >> Ping? >> >> I'm still struggling to understand what you want here; see also Roy's >> comment on the issue in the tracker. >> >> Are you talking about 304 responses, 200 responses, *any* response to >> a GET...? > > It's about generalizing the rule to get a consistent cache behavior > independent of if the request was a GET or HEAD. > > To answer the comment from Roy there is other conditions as well where > the request may need to be forwarded even if the cached entry still > looks valid as such. For example if the request contained Cache- > Control: > max-age=N, Cache-Control: no-cache or at the extreme Cache-Control: > no-store (note: in all these cases as request headers, not response > headers). Without having the statement generalized there is corner > cases > where a GET could still leave old entries in the cache but a HEAD with > the exact same conditions would force them to be invalidated. Mainly > when the cache contains a still seemingly valid response but the > resource has changed on the server and no longer results in a > cacheable > response. I don't follow. If the cache is involved in the request, then it will invalidate the cached response when it receives a 200. If the cache is not involved in the request (no-cache or no-store) then it has no part in the communication and cannot be required to do anything. ....Roy
Received on Monday, 8 June 2009 13:30:04 UTC