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IRI meets RDF meets HTTP redirect

From: Jeremy Carroll <jjc@hpl.hp.com>
Date: Wed, 18 Apr 2007 14:44:59 +0100
Message-ID: <462620DB.3040006@hpl.hp.com>
To: semantic-web@w3.org, www-international@w3.org


I am unclear as to what is the correct reading as an RDF graph of a 
particular representation retrived from the Web.

The representation in question is found by GETting
http://jena.sf.net/test/iri/redirected

this redirects to

http://jena.sourceforge.net/test/iri/redirected
and then to
http://jena.sourceforge.net/test/iri/r%C3%A9sum%C3%A9
which when you apply the URI-to-IRI algorithm of RFC 3987 you get
http://jena.sourceforge.net/test/iri/résumé

and has content as below.

Thus, the graph has one triple, and my uncertainity is about the subject 
of the triple.

In the RDF/XML below the subject is written with the same document 
reference #r

I don't think it is either of these

(a) http://jena.sf.net/test/iri/redirected#r
(b) http://jena.sourceforge.net/test/iri/redirected#r

I think it might be one of these

(c) http://jena.sourceforge.net/test/iri/r%C3%A9sum%C3%A9#r
(d) http://jena.sourceforge.net/test/iri/résumé#r

And while I prefer the latter, I am unclear how to interpret the specs.


If my application does a get on
http://jena.sourceforge.net/test/iri/résumé
then I would expect to see case (d).
Equally if an application does a get on
http://jena.sourceforge.net/test/iri/r%C3%A9sum%C3%A9
then I would expect case (c), but if the application does a get on (a) 
or (b), then these cases are ruled out by RFC 3986, and I have to choose 
between (c) or (d) or something else.


Relevant texts
==============

RFC 3986
5.1.3. Base URI from the Retrieval URI:
[[[
Note that if the retrieval was the
result of a redirected request, the last URI used (i.e., that which
resulted in the actual retrieval of the document) is the base URI.
]]]	

http://www.w3.org/TR/rdf-syntax-grammar/#section-baseURIs
[[
RDF/XML supports XML Base [XML-BASE]
[ ... ]
In RDF/XML, a fragment identifier is transformed into a RDF URI 
reference by appending the fragment identifier to the in-scope base URI.
]]


http://www.w3.org/TR/rdf-concepts/#section-Graph-URIref
[[
Note: this section anticipates an RFC on Internationalized Resource 
Identifiers.
]]

RFC 3987
[[[
     Applications using IRIs as identity tokens with no relationship to a
     protocol MUST use the Simple String Comparison (see section 5.3.1).
]]]
which generally seems relevant to RDF, despite this particular example 
being protocol based.



Content of RDF/XML file
=======================

<?xml version='1.0' encoding='UTF-8'?>

<rdf:RDF
   xmlns:rdf='http://www.w3.org/1999/02/22-rdf-syntax-ns#'
   xmlns:rdfs='http://www.w3.org/2000/01/rdf-schema#'
    >

   <rdf:Description rdf:about="#r">
     <rdfs:comment xml:lang="en">A resource with multiple retrieval URIs 
and IRIs.</rdfs:comment>
   </rdf:Description>

</rdf:RDF>


Jeremy

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Received on Wednesday, 18 April 2007 13:45:20 GMT

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