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Re: quick advice on content negotiation

From: Kingsley Idehen <kidehen@openlinksw.com>
Date: Tue, 08 Dec 2009 13:06:30 -0500
Message-ID: <4B1E95A6.4000904@openlinksw.com>
To: Ted Thibodeau Jr <tthibodeau@openlinksw.com>
CC: Toby Inkster <tai@g5n.co.uk>, nathan@webr3.org, pedantic-web@googlegroups.com, Linked Data community <public-lod@w3.org>
Ted Thibodeau Jr wrote:
>
> On Dec 8, 2009, at 11:52 AM, Toby Inkster wrote:
>> An important question not answered in your message is: what is the URI
>> <http://example.org/user/23> supposed to identify?
>>
>> If it identifies a particular person, then this behavious semantically
>> problematic. Why? Because a web server should never respond "200 OK"
>> to a request for a URI identifying a person, unless it intends to
>> physically chop the person up and pass him/her down the wire to the
>> receiving user agent.
>>
>> If the URI <http://example.org/user/23> is supposed to identify,
>> say, a person's profile, and you have a different URI to represent
>> the person themselves (e.g. <http://example.org/user/23#me>) then
>> the connection negotiation setup you describe is fine.
>
>
> I don't agree.
>
> What is the MIME type for a person?
>
> 200 OK is tied to a combination of URI *and* Accept: (and other)
> headers.  Not just the URI.
>
> I can absolutely GET the URI for you, the person, with a 200 OK
> response -- *if* I have requested an available and transmissable
> *representation* of that URI.  (And the response should include
> headers explicitly describing which representation I'm GETting.)
>
> Be seeing you,
>
> Ted
>
>
>
Ted,

re. the above, do:  s/URI/URL/g  :-)

Then we get to where we need to be i.e. de-constructing  the Generic 
HTTP URIs (a URL isn't Generic, its a Locator/Address oriented Identifier).

Re. HTTP based Linked Data (Hyper Linked Data or Hyperdata), Real World 
Objects (which are neither resources or information resources) are 
explicitly associated with Representations of their Metadata via 
Identity/Access duality of Generic HTTP URI abstraction. Said 
abstraction embodies:

1. Metadata Subject Identifier
2. Metadata Container (Resource) Address
3. EAV model Graph Pictorial based on Constellation of Characteristics 
(Attributes) coalesced around Subject Identifier

Thus, a single Generic HTTP URI offers a composite key, that is also a 
powerful message unit for RESTful data interaction via HTTP protocol.

Different route to your conclusions:
Mime Type equivalents exist in our realm, outside the Web (e.g. our 
bodies), but even here the URI Referent (we call this "Soul") is 
eternally mercurial (we describe aspects at best), so 200 OK should 
never apply to a pure Identifier i.e.,  one unconstrained by location, 
value, or shape :-)

Links:

1.  http://tr.im/H2gm -- The URI, URL, and Linked Data Meme's Generic 
HTTP URI (an old post about URL and Generic HTTP URI confusion)

-- 


Regards,

Kingsley Idehen	      Weblog: http://www.openlinksw.com/blog/~kidehen
President & CEO 
OpenLink Software     Web: http://www.openlinksw.com
Received on Tuesday, 8 December 2009 18:07:05 GMT

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