Re: Last call for feedback before Drupal 7 alpha release

Hi Manu,

Thank you for your feedback!

On Tue, Jan 12, 2010 at 10:56 AM, Manu Sporny <msporny@digitalbazaar.com>wrote:

>
> === Repeated Triples ===
>
> Looking at this page:
>
> http://drupalrdf.openspring.net/node/106
>
> There are a number of triples that are duplicated on that page.
> Duplicating these triples is fairly harmless, but I wanted to make sure
> that this was intended instead of accidental.
>
> <http://drupalrdf.openspring.net/user/2>
>   <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
>      <http://rdfs.org/sioc/ns#User> .
>
> <http://drupalrdf.openspring.net/user/2>
>   <http://xmlns.com/foaf/0.1/name>
>      "John" .
>
> You could keep track of the triples you generate via the code and not
> generate duplicate triples. Not sure the added complexity would be worth
> it for Drupal, though.
>

I see what you mean. As you say that would be added complexity and I'm not
sure it would cut it performance wise. Right now we blindly output these
triples (or rather decorate the HTML with RDFa attributes) for each template
of HTML. Adding a condition would mean to have extra storage which
altogether might take longer than simply adding these attributes all the
time. Note that we don't have an RDF storage in core yet, so maybe for
Drupal 8 :)


>
> === Multiple Types ===
>
> Often, comments and posts are marked up with two rdf:types. For example,
> this page:
>
> http://drupalrdf.openspring.net/node/106
>
> generates the following triples:
>
> <http://drupalrdf.openspring.net/comment/696#comment-696>
>   <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
>      <http://rdfs.org/sioc/ns#Post> .
>
> <http://drupalrdf.openspring.net/comment/696#comment-696>
>   <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
>      <http://rdfs.org/sioc/types#Comment> .
>
> Since sioc:Comment is a owl:subClassOf sioc:Post, I don't think there is
> a strong reason for you to generate the sioc:Post triple. The same
> applies to dc:date and dc:created:
>
> <http://drupalrdf.openspring.net/node/106>
>   <http://purl.org/dc/terms/date>
>      "2009-01-07T10:58:54-06:00" .
>
> <http://drupalrdf.openspring.net/node/106>
>   <http://purl.org/dc/terms/created>
>      "2009-01-07T10:58:54-06:00" .
>
> and to blog posts:
>
> <http://drupalrdf.openspring.net/node/106>
>   <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
>      <http://rdfs.org/sioc/ns#Post> .
>
> <http://drupalrdf.openspring.net/node/106>
>   <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
>      <http://rdfs.org/sioc/types#BlogPost> .
>
> You may be doing this because there are reasoning agents out there that
> don't understand rdfs:subPropertyOf or OWL. Again, just making sure that
> this was done on purpose and not by accident.
>

Correct, we materialize subClassOf and subPropertyOf so we don't require
people to have reasoning agents. I'm not sure when web browsers like FireFox
will enable reasoning on the fly when parsing RDFa. We want to have
sioc:BlogPost to enable accurate SPARQL querying for example, but some tools
might not know what to do with it, and might not infer it's also a
sioc:Post, so we prefer to have it materialized.


>
> > I feel uneasy when people ask "How can I see the RDFa?" and
> > I can't give them a compelling RDFa parser library which supports 100%
> > of the RDFa markup we output.
>
> Have you tried Fuzz[1], yet? There was a new release about a month ago.
> The parser passes 100% of the RDFa Test Suite and is a native RDFa
> Processor and display UI for Firefox (runs on Windows, Mac OS X and
> Linux). The UI is rough, but you should be able to see all of the
> triples that are generated.
>

I tried it, but somehow the relation <comment> sioc:reply_of <node> is not
appearing in the Fuzz Example Triple Display (while it is present on other
parsers). I will add this to the bug tracker.

Steph.


>
> Drupal 7 is looking great... good luck on the upcoming set of releases!
>
> -- manu
>
> [1] http://rdfa.digitalbazaar.com/fuzz/trac/
>
> --
> Manu Sporny (skype: msporny, twitter: manusporny)
> President/CEO - Digital Bazaar, Inc.
> blog: Monarch - Next Generation REST Web Services
> http://blog.digitalbazaar.com/2009/12/14/monarch/
>