Re: Semantic content negotiation (was Re: expectations of vocabulary)

On 7/27/06, Xiaoshu Wang <wangxiao@musc.edu> wrote:

> Whatever the HTTP headers ask, the resource is still treated as a cohesive
> unit.  It applies to the resource in an all-or-none fashion.  If any request
> demands the resource be broken into pieces, I think it steps out of the
> boundary of HTTP GET.

Sure. But no-one is talking about breaking resources into pieces, just
providing alternate representations of the same resource. In RDF terms
those representations may have graph/subgraph relationships with each
other, but that's absolutely irrelevant as far as HTTP is concerned.
HTTP does not mandate any particular part-whole logic. A resource can
be anything that has identity, but the relevant specs make no demands
on how identity between two resources is determined beyond the syntax
of their identifiers.

I also don't think anyone is suggesting that the request *demands*
anything - just expresses client preferences, which may be ignored.

For reference:

 resource
    A network data object or service that can be identified by a URI,
as defined in section 3.2. Resources may be available in multiple
representations (e.g. multiple languages, data formats, size, and
resolutions) or vary in other ways.

 representation
    An entity included with a response that is subject to content
negotiation, as described in section 12. There may exist multiple
representations associated with a particular response status.

http://www.w3.org/Protocols/rfc2616/rfc2616-sec1.html#sec1.3

Cheers,
Danny.
-- 

http://dannyayers.com