W3C home > Mailing lists > Public > ietf-http-wg@w3.org > October to December 2009

Re: What are "appropriate Cache-Control or Expires header fields"

From: Henrik Nordstrom <henrik@henriknordstrom.net>
Date: Fri, 20 Nov 2009 20:09:29 +0100
To: Brian Smith <brian@briansmith.org>
Cc: "'HTTP Working Group'" <ietf-http-wg@w3.org>
Message-Id: <1258744169.19912.602.camel@localhost.localdomain>
mån 2009-10-12 klockan 20:22 -0500 skrev Brian Smith:
> What, precisely, must the Cache-Control or Expires header fields contain in
> order to make a response to a POST, a 302 response, a 303 response, or a 307
> response cacheable? This seems to not be specified anywhere in the
> specification.

For responses to GET/HEAD it means that heuristic freshness calculation
is not allowed, only explicit freshness indication via Cache-Control or

If Cache-Control max-age / s-maxage or Expires is present and no other
directives prevent caching then the response is cacheable.

POST (and other non-GET methods) is a bit different.. cache model is a
bit different for non-GET methods. Not even sure there is even a
beginning of a consensus on what the cache model for non-GET methods
would be. (except for HEAD which is GET with a slight twist)

Received on Friday, 20 November 2009 19:10:05 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 1 March 2016 11:10:52 UTC