Re: conneg considered harmful

On Feb 16, 2013, at 1:01 AM, Peter Williams <[email protected]> wrote:
> Most of those don't talk about why using content negotiation is bad in general.  Instead they talk about how truly different resources should have their own uris even if they are variants of one another (eg articles about the same subject written in different human languages). That seems very reasonable.  However, those arguments don't apply to situations where multiple, truly mechanically translatable, representations of a single resource exist.
> One of those mention that conneg has a negative effect on caching. Is being harder to cache the only ill effect of sever driven conneg?
> 
Here are just some additional references about content negotiation:

http://trac.tools.ietf.org/wg/httpbis/trac/ticket/81
http://trac.tools.ietf.org/wg/httpbis/trac/changeset/745
http://tools.ietf.org/id/draft-masinter-mime-web-info-00.html#anchor6
http://lists.w3.org/Archives/Public/www-tag/2009Feb/0074.html

There are numerous references that I found while searching to conneg being a "bad idea but okay in some contexts" but AFAICF no description of use-cases for which some say it does make sense.  

-Mike



On Feb 16, 2013, at 1:01 AM, Peter Williams <[email protected]> wrote:

> 
> Most of those don't talk about why using content negotiation is bad in general.  Instead they talk about how truly different resources should have their own uris even if they are variants of one another (eg articles about the same subject written in different human languages). That seems very reasonable.  However, those arguments don't apply to situations where multiple, truly mechanically translatable, representations of a single resource exist.
> 
> One of those mention that conneg has a negative effect on caching. Is being harder to cache the only ill effect of sever driven conneg?
> 
> Peter
> Barelyenough.org
> 
> On Feb 15, 2013 3:31 PM, "Alan Dean" <[email protected]> wrote:
> Perhaps it is worth referencing some other other Fielding quotes on the subject:
> 
> https://delicious.com/alan.dean/Roy.Fielding+conneg
> 
> Regards,
> Alan Dean
> 
> 
> On Fri, Feb 15, 2013 at 8:21 PM, Peter Williams <[email protected]> wrote:
>  
> Eric,
> 
> That is an interesting quote. I have occasionally heard
> unsubstantiated claims regarding the badness of accept header based
> content negotiation. It is interesting that Roy perceives it as
> "revolting".
> 
> Personally, i rather like it but perhaps i am missing something
> important. I'd definitely like to hear someone (or multiple someones)
> actually articulate what they perceive as problematic about it. So far
> i don't recall ever reading a discussion of the downsides that got
> beyond "i don't like it" or "it is hard for me to implement" (neither
> of which resonate with me).
> 
> 
> 
> On Wed, Feb 13, 2013 at 9:04 AM, Eric J. Bowman [email protected]> wrote:
> > Mark Baker wrote:
> >>
> >> Besides, client driven uses hypermedia so is way more RESTful.
> 
> Mark, can you explain a bit more why you think this? It is not clear
> to me why avoiding this particular part of http's uniform interface
> would make a client more RESTful.
> 
> Peter
> barelyenough.org
> 
> 
> 
>