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Re: [RESEND] Media types for RDF languages N3 and Turtle

From: Graham Klyne <GK@ninebynine.org>
Date: Wed, 19 Dec 2007 16:10:19 +0000
Message-ID: <4769426B.2010003@ninebynine.org>
To: "Eric Prud'hommeaux" <eric@w3.org>
CC: ietf-types@iana.org, "Sean B. Palmer" <sean@miscoranda.com>, Tim Berners-Lee <timbl@w3.org>, "Daniel W. Connolly" <connolly@w3.org>, Dave Beckett <dave@dajobe.org>, Lee Feigenbaum <lee@thefigtrees.net>, Garret Wilson <garret@globalmentor.com>, Dan Brickley <danbri@danbri.org>, www-archive@w3.org
I've not read the latest emergence of this thread with a fine tooth comb, but I
would suggest:

(1) use application/(something) rather than text/(something) in *all* cases
where the content is not primarily for human consumption - i.e. if you expect to
do anything other than display as-is on a character display.  I don't think that
*any* rendering of RDF is really primarily constructed for direct human
interpretation.

(2) rather than use the +suffix for cases other than +xml, use -suffix.  Or, at
least, provide a compelling example of two different media types with +foo
suffix that might fall back to being processed by a common software package
associated with that suffix.

Thus:
   application/rdf+xml
   application/octet-stream (ntriples)
   application/rdf-turtle
   application/rdf-n3

#g
--

Eric Prud'hommeaux wrote:
> [resent, correcting typos and thinkos]
> 
> Hi all, there are a couple languages that have been used for a while,
> turtle and n3, and I am trying work out the right media types to
> register for them.
> 
> 
> == Cast of Characters
> ╔══════════╦══════════════════════════════╦══════════════════════╗
> ║  name    ║            role              ║  current media type  ║
> ╠══════════╤══════════════════════════════╤══════════════════════╣
> ║ RDF      │ data model                   │ N/A                  ║
> ╟──────────┼──────────────────────────────┼──────────────────────╢
> ║ RDFXML   │ XML serialization of RDF     │ application/rdf+xml  ║
> ╟──────────┼──────────────────────────────┼──────────────────────╢
> ║ ntriples │ simple serialization of RDF  │ text/plain           ║
> ╟──────────┼──────────────────────────────┼──────────────────────╢
> ║ turtle   │ textual serialization of RDF │ application/x-turtle ║
> ╟──────────┼──────────────────────────────┼──────────────────────╢
> ║ n3       │ extension¹of turtle language │ text/rdf+n3 (not     ║
> ║          │ expressing a superset of RDF │          registered) ║
> ╚══════════╧══════════════════════════════╧══════════════════════╝ 
> 
> ¹ The origins of turtle and n3 are complicated, but this is the
>   most practical model for media type consideration.
> 
> These languages will be published under http://www.w3.org/TR/

> (which implies certain persistance and update policy) as soon
> as I work out what to include in the media type registration.
> In the mean time, see
>   http://www.dajobe.org/2004/01/turtle/#sec-mime

>   http://www.w3.org/DesignIssues/Notation3

> 
> Neither the turtle nor n3 media types are registered. I seek advice
> from the community on exactly how to register them, as I will have
> to beat out some sort of consensus in order to register them.
> 
> 
> == Issues
> • subsumption relationshop — n3 subsumes turtle in both data model and
>   grammar. To that end, text/n3; and text/n3; profile=turtle have been
>   suggested. Another suggestion has been text/rdf+n3 and
>   text/rdf+turtle , in somewhat the spirit of XML (where the +xml
>   indecates the that it's the XML encoding of the preceding datatype).
> 
> • subtree — turtle and n3 are certainly more human-readable than
>   ntriples (as they are basically extensions of ntriples, with
>   namespace prefixes and abbreviations for some atoms). The default
>   character encoding of us-ascii is certainly outdated, and doesn't
>   make sense for any of these languages. Garret Wilson (Cc'd) raised
>   the question of whether a text/ registration may force the charset
>   to be, say, utf-8². Both n3 and turtle, as well as related langs
>   like SPARQL, are explcitly utf-8. Can the registration include text
>   like "The encoding is always UTF-8"? Would that mean that the
>   media type would not need a constant charset parameter?
> 
> ² http://lists.w3.org/Archives/Public/www-rdf-comments/2007OctDec/0017

> 
> 
> == Strawman
> Let me propose:
>   n3: text/rdf+n3
>   turtle: text/rdf+turtle
> with
> [[
> Encoding considerations: The encoding is always UTF-8
> ]]
> and the expectation that
> [[
> Content-type: text/rdf+n3
> ]]
> (or +turtle) fully specifies the media type and the
> character encoding.
> 
> 
> A plea to all: bear in mind that this consensus bit is a hard job,
> and that the world will be much better off if we can reach a timely
> compromise. We've suffered for five years without these media types
> so let's keep our mission reallistic.

-- 
Graham Klyne
For email:
http://www.ninebynine.org/#Contact


Received on Thursday, 20 December 2007 09:20:14 GMT

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