- From: Julian Reschke <julian.reschke@gmx.de>
- Date: Wed, 31 Oct 2012 16:45:55 +0100
- To: Zhong Yu <zhong.j.yu@gmail.com>
- CC: Martin Thomson <martin.thomson@gmail.com>, Dan Winship <dan.winship@gmail.com>, HTTP Working Group <ietf-http-wg@w3.org>
On 2012-10-31 16:30, Zhong Yu wrote: > On Wed, Oct 31, 2012 at 2:13 AM, Julian Reschke <julian.reschke@gmx.de> wrote: >> On 2012-10-30 21:40, Zhong Yu wrote: >>> >>> Got it. In the spec, >>> http://tools.ietf.org/html/draft-ietf-httpbis-p2-semantics-21#section-8.2 >>>> >>>> Additional header fields define metadata about the selected >>>> representation, which might differ from the representation included in the >>>> message for responses to some state-changing methods >>> >>> >>> So if the current representation has ETag=v1, and PUT sends a new >>> representation to which the server assigns ETag=v2, the response to >>> PUT may contain ETag of the old representation. (This was not in >>> RFC2616) >>> ... >> >> >> Why would it contain the old ETag? > > According to the same section in the spec > >> We use the term "selected representation" to refer to the the current representation of a target resource that would have been selected in a successful response if the same request had used the method GET and excluded any conditional request header fields. > > In my example, the request is > PUT /resource HTTP/1.1 > > If the same request had used the method GET > GET /resource HTTP/1.1 > > the current representation with ETag=v1 would have been selected. > > Thereforev1 is the selected representation. If the response contains > ETag header, it is a metadata about the selected representation, i.e. > v1. > ... Well, that's certainly not what we *want* the spec to say. Roy? Best regards, Julian
Received on Wednesday, 31 October 2012 15:46:27 UTC