SWAD-Europe Simple Knowledge Organisation System (SKOS) API
               Web Service API for a thesaurus service

     http://www.w3.org/2001/sw/Europe/reports/thes/skosapi.html

We are pleased to announce the initial release of the SKOS API
developed by the SWAD-Europe[1] project thesaurus activity[2]
an EU IST-7 funded project.

The SKOS API defines a web service providing a core set of methods
for accessing and querying a thesaurus or terminological resource
based on the SKOS-Core schema, as described in the SKOS-Core Guide[3].

This is an initial release which we expect will evolve in response to
input from the wider community.  Our goal is to contribute to the
development of a web service API that will be suitable for widespread
adoption, which in turn will promote ease of interoperability and
re-use of information systems that exploit thesauri and/or other
kinds of terminological resource.

We ask at this stage for initial feedback from web service
developers, systems designers and KOS experts looking to expose or
access this kind of functionality

In particular, we have the following open issues, in no particular
order (some of these are from the 'scratch pad' ServiceBits class[4] )

- How much information to return in Concept fields versus API calls.
- In our implementation, should we use the SOAP encoding model or
  literal RDF/XML (for example) to represent concepts and
  relations. Or both.
- Try to use xsd:anyURI instead of a separate URI class
- Versioning of the interface, do we add a getVersion() method.
- Should we provide access to RDF query support where available (like
Joseki)
- A REST API would be good to have especially as this is a
  non-side effecting API, so HTTP GET operations would be safe.
- Returning values as singletons compared to arrays of size 1
- What fields of concepts should regexe searches match.
- Method doubling for thesaurus parameters versus allowing Null values
  (we are aware WS-I Basic Profile recommends against method
  overloading, so we avoid that)

A demonstration implementation of using this web service API is
currently under development which will host several thesauri in the
SKOS schema[5] and provide a public web service.

Please direct all feedback to the public mailing list:
[log in to unmask] list, more details are available at [6].

Alistair Miles
Nikki Rogers
Dave Beckett


[1] http://www.w3.org/2001/sw/Europe/
[2] http://www.w3.org/2001/sw/Europe/reports/thes/
[3] http://www.w3.org/2001/sw/Europe/reports/thes/1.0/guide/
[4] http://www.w3.org/2001/sw/Europe/reports/thes/api/docs/
[5] http://www.w3.org/2004/02/skos/core
[6] http://lists.w3.org/Archives/Public/public-esw-thes/