Re: Prefer Draft Feedback

On Mon, Dec 12, 2011 at 1:15 PM, Julian Reschke <julian.reschke@gmx.de> wrote:
> On 2011-12-08 18:56, James Snell wrote:
>>
>> Ok, a new draft has been published.
>>
>> http://www.ietf.org/id/draft-snell-http-prefer-07.txt
>>
>> After discussing caching issues with Mark in detail, I've made a
>> number of important changes to the draft... specifically, it is
>> important to point out that Prefer was always intended to be a
>> behavior-negotiation mechanism, not content-negotiation. While the
>> application of a behavioral preference could potentially impact the
>> construction of a response, implementations should avoid utilizing
>> preferences in a way that causes a variance in the caching of a
>> response. For that reason, I added a new short section detailing cache
>> considerations and removed the detail preference. Basically, if you're
>> using Prefer for content-negotiation, you're likely doing it wrong.
>
>
> Not convinced. Where's the difference? If the response without "Prefer"
> would have been cacheable, and the presence of the Prefer header field
> changes the response I receive, how is that *not* content negotiation?
>
>

I tend to view it more as behavior negotiation but it is definitely a
grey area. Going to be thinking this through a bit more.