W3C home > Mailing lists > Public > www-archive@w3.org > January 2008

Media types for RDF languages N3 and Turtle

From: Eric Prud'hommeaux <eric@w3.org>
Date: Mon, 17 Dec 2007 10:16:54 -0500
To: ietf-types@iana.org
Cc: "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>, Graham Klyne <GK@ninebynine.org>, Dan Brickley <danbri@danbri.org>, w3-archive@w3.org
Message-ID: <20071217151654.GK8244@w3.org>
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

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  character encoding of iso-8859-1 is certainly outdated, and doesn't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
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.

office: +1.617.258.5741 NE43-344, MIT, Cambridge, MA 02144 USA
mobile: +1.617.599.3509

Feel free to forward this message to any list for any purpose other than
email address distribution.

Received on Tuesday, 1 January 2008 17:32:34 UTC

This archive was generated by hypermail 2.4.0 : Friday, 17 January 2020 22:33:19 UTC