- From: Julian Reschke <julian.reschke@gmx.de>
- Date: Mon, 04 Nov 2013 23:55:23 +0100
- To: "Henry S. Thompson" <ht@inf.ed.ac.uk>, ietf-http-wg@w3.org
- CC: apps-discuss@ietf.org, www-tag@w3.org
On 2013-11-04 17:53, Henry S. Thompson wrote: > It's my impression that content negotiation hasn't turned out to play > the kind of significant role in Web Architecture in general, or in > HTTP use in particular, that was expected for it. > > I think the section on conneg in p2-semantics [1] is so out-of-step > with actually deployment, usage and expectations that to publish it as > it stands would be a serious mistake. > > In particular, the discussion of the relative disadvantages of the > newly (re-)named 'proactive' and 'reactive' variants are not only > out-of-date, but also this discussion appears to at least this reader > to amount to a recommendation for 'reactive' negotiation. Yet as far > as I can tell no user agents _or_ servers actually support this > approach today, as it's described here. > > I was sufficiently concerned about this question to undertake a > moderately extensive empirical investigation [2]. To summarise > perhaps too briefly, I found _no_ evidence of the use of reactive > conneg in over 75 million HTTP request/response exchanges. > ... Reactive conneg isn't just about 300s and 406s. Another example would be a representation returned with a 200 response that contains links to alternate versions of the content. That's what the "If the user agent is not satisfied by the initial response representation, it can perform a GET request on one or more of the alternative resources, selected based on metadata included in the list, to obtain a different form of representation for that response. Selection of alternatives might be performed automatically by the user agent or manually by the user selecting from a generated (possibly hypertext) menu." in <http://greenbytes.de/tech/webdav/draft-ietf-httpbis-p2-semantics-24.html#rfc.section.3.4.2.p.1> is about. Best regards, Julian
Received on Monday, 4 November 2013 22:55:53 UTC