- From: Thomas Fossati <TFossati@velocix.com>
- Date: Tue, 9 Oct 2012 15:05:34 +0000
- To: Amos Jeffries <squid3@treenet.co.nz>
- CC: "<ietf-http-wg@w3.org>" <ietf-http-wg@w3.org>
On 9 Oct 2012, at 01:01, Amos Jeffries wrote: > On 09.10.2012 03:04, Thomas Fossati wrote: >> Hi all, >> >> maybe a dumb one, but I couldn't find any decisive anchor for the >> following question: suppose my cache receives a conditional GET for a >> resource for which it has a fresh representation, should Age be sent >> back to the requester in a 304 ? >> >> The two points in the current spec that got me confused are: >> >> - p6, Section 4: "When a stored response is used to satisfy a request >> without validation, a cache MUST include a single Age header field in >> the response with a value equal to the stored response's current_age." >> >> - p4, Section 4.1 after the paragraph listing the mandatory headers >> for 304 (which do not include Age): "Since the goal of a 304 response >> is to minimize information transfer when the recipient already has one >> or more cached representations, the response should not include >> representation metadata other than the above listed fields unless said >> metadata exists for the purpose of guiding cache updates (e.g., future >> HTTP extensions)." >> >> TIA, Thomas. > > IMO, the Age header is not useful in this case. Since the requestor already appears to have a copy of the representation, thus already has or can calculate its Age. If the requestor does not already have a coy (was checking for existence etc) then it does not need to know Age, but only existence and future lifetime - which are included via the other 304 headers. That seems reasonable, thanks. The MUST about Age in Section 4 of p6 should then be amended to take care of 304, or am I missing some other point in the spec that already narrows the scope of this requirement ?
Received on Tuesday, 9 October 2012 15:06:10 UTC