Linked Data

CLLD applications publish Linked Data as follows:

  1. VoID description deployed at <base-url>/void.ttl (also via content negotiation)

  2. RDF serializations for each resource available via content negotiation or by appending a suitable file extension.

  3. dumps pointed to from the VoID description

CLLD core resources provide serializations to RDF+XML via mako templates. This serialization is used as the basis for all other RDF notations. The core templates can be overwritten by applications using standard mako overrides. Custom resources can also contribute additional triples to the core serialization by specifying a __rdf__ method.

Vocabularies

Types

Resources modelled as clld.db.models.common.Language are assigned dcterm’s LinguisticSystem class or additionally a subclasses of GOLD’s Genetic Taxon or additionally the type skos:Concept.

clld.db.models.common.Source are assigned types from the Bibliographical Ontology.

Design decisions

1. No “303 See other”-type of redirection. While this approach may be suitable to distinguish between real-world objects and web documents, it also blows up the space of URLs which need to be maintained, and raises the requirements for an application serving the linked data (i.e. a simple web server serving static files will no longer do, at least without complicated configuration). Since we want to make sure, that the data of the CLLD project can be made available as Linked Data for as long as possible, minimizing the requirements on the hosting requirement was regarded more important than sticking to the best practice of using “303 See other”-type redirects.