RE: #110: how to determine what entity a response carries

Mark Nottingham wrote:

> 3) If the response has a Content-Location header, and that URI is
>    the same as the request-URI the response is a representation
>    of the request-URI.

This kind of rule is only helpful if the application is going to save the
response in a cache,  avoiding a GET to the request-URI. But, another part
of the spec. already says we cannot add a response to a cache based on the
Content-Location header; we can only use Content-Location for
*invalidation*.

> The bigger question, though, is how this affects the spec. 

Anybody that needs to make these kinds of inferences can infer the rules
from the spec as you did. Adding some algorithm for this to the spec. would
be redundant at best (if the algorithm was completely consistent with the
rest of the spec) and contradictory/misleading at worst.

> I think the main impact -- if we can come to agreement, of course
> -- is on issues like
> <http://trac.tools.ietf.org/wg/httpbis/trac/ticket/22>.

Issues like #22 will be easy to resolve once it is acknowledged that "the
response that would be returned upon a GET" only makes sense for HEAD and
not PUT/POST/DELETE/etc. due to content negotiation.

Regards,
Brian