Drupal 7 and RDF
Stéphane Corlosquet, <[email protected]>
- Software engineer, MGH
- Drupal 7 core RDF maintainer - SemWeb geek
Linked Data Ventures, MIT, Oct 2010
This work is licensed under a Creative Commons Attribution 3.0 License, with attribution to Stéphane Corlosquet
Drupal
● Dries Buytaert - small news site in 2000
● Open Source - 2001
● Content Management System
● LAMP stack
● Non-developers can build sites
and publish content
● Control panels instead of code
http://www.flickr.com/photos/funkyah/2400889778 /
Drupal
● Open & modular
architecture
● Extensible by modules
● Standards-based
● Low resource hosting
Building a Drupal site
Building a Drupal site
Building a Drupal site
● Create the content types
you need:
Blog, article, wiki, forum, polls, image, video, podcast,
e-commerce... (be creative)
Building a Drupal site
● Enable the features you
want:
Comments, tags, voting/rating, location, translations, revisions, search...
Building a Drupal site
● Place links in the
navigation bars and blocks
● Build Views over your
data
● Skin your site: theming
Building a Drupal site
6000 free contributed modules ● Google Analytics ● Wysiwyg ● Captcha ● Calendar ● XML sitemap ● Five stars ● Twitter ● ... http://www.flickr.com/photos/kaptainkobold/1422600992/Drupal inside
● Database storage (PDO) ● Cron
● Queue / batch API ● File management ● User management ● Form API
● Security
User experience
The Drupal Community
The Drupal Community
http://webchick.net/node/80
“It’s really the Drupal community and not so much the software that makes the Drupal project what it
is. So fostering the Drupal community is actually more important than just managing the code base.” -
200+ Local user groups
Doubles in size each release
Doubles in size each release
● Drupal 6 (stable) - 325,145+ sites
● Drupal 7 (beta 1) - 20,000+ sites
● Total estimation 500,000 sites (1% of the Web)
http://buytaert.net/20000-drupal-gardens-sites http://drupal.org/project/usage/drupal
Who uses Drupal?
Try Drupal 7
● Download and Install Drupal 7
● Grab latest release http://drupal.org/project/drupal
● Mac OS: MAMP http://www.mamp.info/
● Acquia Stack http://acquia.com/downloads
● Drupal Gardens: free Drupal 7 site
History of RDF in Drupal
● rdf.php (2000, Dries)
● FOAF, vCard (2004, walkah)
● Relationship (2005, dman)
● Semantic Search (2006, hendler)
● RDF (2007, Arto)
● OpenCalais (febbraro, 2008)
● RDF CCK (2008, scor)
Experiment prior Drupal 7
● Expose Drupal's data in
RDF ● Automatically ● No RDF expertise required ● Module based http://www.flickr.com/photos/neys/238686518 7
Architecture
● User driven data model
● Content type = RDF class
● Field = RDF property
● Node = RDF resource
http://www.flickr.com/photos/docman/221656821 0
Mapping to RDF
● site:Person a rdfs:Class;
rdfs:subClassOf foaf:Person.
● site:first_name a rdf:Property;
rdfs:subPropertyOf foaf:firstName.
Experiment continued
● 1. Automatic site vocabulary generation
● 2. Mapping Content Models to existing
ontologies
● 3. Data endpoint for SPARQL querying
Drupal 7 and RDF
● Drupal 7 core is RDFa enabled!
● RDFa output by default on blogs, forums,
comments, etc. using FOAF, SIOC, DC, SKOS
Drupal 7 contributed modules
● http://drupal.org/project/rdf
● Import vocabularies
● Interface for mappings
● http://drupal.org/project/sparql_ep
● SPARQL endpoint on Drupal data
RDFDB: an RDF Database API
● Access RDF stores via a consistent API
● SPARQL 1.1
● Vendor agnostic
● Similar to Drupal 7 Database abstraction layer
● rdfdb_insert_data($graph, $triples)->execute();
● rdfdb_select('?g ?s ?p ?o')->where('GRAPH ?g { ?
RDFDB: an RDF Database API
● Similar to Drupal 7 Database abstraction layer
● rdfdb_insert_data($graph, $triples)->execute(); ● rdfdb_select('?s ?p >where('?s ?p
?o')->limit(10)->execute();
● rdfdb_clear($graph)->execute()
● Do not worry about what RDF store the
RDFDB: an RDF Database API
● Connection info:
● Support for master/slave servers
● Drivers for ARC2, Virtuoso, 4store
RDFDB: an RDF Database API
● Why an abstraction layer?
● Every store has its own way to implement SPARQL
updates, some are RESTful, some others have their own SPARQL update syntax.
● ARC2: SPARQL+ via POST requests
● 4store: POST, PUT and DELETE requests
● Download
How to get involved
● So many ways... code, documentation, support,
translations, graphic design
● http://drupal.org/getting-involved
How to get involved
● Subscribe to the Semantic Web group at
http://groups.drupal.org/semantic-web
Questions?
Good luck!