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Re: Anyone able to help improve Dublin Core namespace XSLT to support RDFS RDFa?

From: Thomas Baker <tom@tombaker.org>
Date: Fri, 11 May 2012 14:07:03 -0400
To: Gregg Kellogg <gregg@greggkellogg.net>
Cc: Danny Ayers <danny.ayers@gmail.com>, Dan Brickley <danbri@danbri.org>, public-rdfa <public-rdfa@w3.org>, "hugh@hubns.com" <hugh@hubns.com>
Message-ID: <20120511180703.GA27286@julius>
On Fri, May 11, 2012 at 01:31:00PM -0400, Gregg Kellogg wrote:
> There are some minor issues remaining that I'm looking at right now:
> 
> It looks like rdfs:command and dc:description are reduced in the RDF/XML output. For example, dc:Agent:
> 
> <rdf:Description rdf:about="http://purl.org/dc/terms/Agent">
>   <rdfs:label xml:lang="en-US">Agent</rdfs:label>
>   <rdfs:comment xml:lang="en-US">A resource that acts or has the power to act.</rdfs:comment>
>   <dcterms:description xml:lang="en-US">Examples of Agent include person, organization, and software agent.</dcterms:description>
>   <rdfs:isDefinedBy rdf:resource="http://purl.org/dc/terms/"/>
>   <dcterms:issued>2008-01-14</dcterms:issued>
>   <rdf:type rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/>
>   <rdf:type rdf:resource="http://purl.org/dc/terms/AgentClass"/>
>   <dcterms:hasVersion rdf:resource="http://dublincore.org/usage/terms/history/#Agent-001"/>
> </rdf:Description>

I'm not sure what you mean by "reduced".  The Web document says:

    Term Name:    Agent
    URI:          http://purl.org/dc/terms/Agent
    Label:        Agent
    Definition:   A resource that acts or has the power to act.
    Comment:      Examples of Agent include person, organization, and software agent.
    Type of Term: Class
    Instance Of:  http://purl.org/dc/terms/AgentClass
    Version:      http://dublincore.org/usage/terms/history/#Agent-001

This matches the RDF/XML output except for the addition, in the RDF/XML, of
rdfs:isDefinedBy and of the date issued (of the individual property or class).

> The HTML output ends up pulling in several definitions for
> http://purl.org/dc/dcam/VocabularyEncodingScheme. Perhaps this needs some
> additional filter to not define anything not in dcterms?

In the dcmi-terms/index.shtml output (RDFa-to-Turtle) I'm looking at, I only
see one entry for VocabularyEncodingScheme, as in [1]:

    <http://purl.org/dc/dcam/VocabularyEncodingScheme>
       dc:issued "2008-01-14";
       rdfs:identifier <http://purl.org/dc/dcam/VocabularyEncodingScheme>;
       rdfs:seeAlso <http://dublincore.org/documents/2007/06/04/abstract-model/>;
       rdf:type rdfs:Class;
       dc:hasVersion <http://dublincore.org/usage/terms/history/#VocabularyEncodingScheme-001> .

The rdfs:identifier is wrong, if only because rdfs:identifier does not exist...

Compared to the Web document [1], what is systematically missing in this
RDFa-to-Turtle output (and in the RDFa-to-Turtle output for all other
properties and classes) is:

    rdfs:label for the "Term Name"
    rdfs:comment for the "Definition"
    dcterms:description for the "Comment" (though not for "VocabularyEncodingScheme", which does not have one)

What is systematically missing compared to the RDF/XML output (e.g., [2]):

    rdfs:isDefinedBy <http://purl.org/dc/terms/>

[1] http://dublincore.org/documents/dcmi-terms/#dcam-VocabularyEncodingScheme
[2] http://dublincore.org/2010/10/11/dcterms.rdf

> RDF/XML version does not provide a datatype definition for dcterms:issued and
> dcterms:modified. This is done in HTML using the <time> element, where the
> datatype is implicit.

+1

> HTML version outputs rdfs:identifier equivalent to the subject. This is easily omitted.

+1 (see above)

> The XSL was not outputting RDF for text properties, which I've corrected in
> my working branch.

+1 - I should have read the message through before responding...!

The other error I see is: 

   rdfs:domain dc:Collection;

where Collection is a term from the DCMI Type Vocabulary, not /terms/, and
should thus be given with its full URI <http://purl.org/dc/dcmitype/Collection>
or using a @prefix for the Type Vocabulary:

   rdfs:domain dc:Collection;
   rdfs:domain dc:Collection;
   rdfs:domain dc:Collection;

Do I correctly understand that if the HTML/RDFa document completely expresses the 
contents of the current HTML and RDF/XML documents, and we direct the PURLs to that 
document, we could delete (or rather archive) the XSL scripts used to generate the
RDF/XML?  The other simplifications I would like to make are:

-- Delete (or archive) the XSL script for generating the (redundant) stand-alone
   DCMI Type Vocabulary document.

-- Revert to the pre-RDFa XSL script for generating the "history" document [2].

This means that only one XSL script for generating RDFa would need to be
maintained.

It looks to me like we are getting very close!

Tom

[2] http://dublincore.org/usage/terms/history/

-- 
Tom Baker <tom@tombaker.org>
Received on Friday, 11 May 2012 18:07:41 GMT

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