ANN: A new Linked Data interface and fresh data for LinkedGeoData!

[Claus Stadler]

Hello LGD community,

Lately, it has become a bit silent around LinkedGeoData, but behind the scenes development is still progressing.
Today, LGD has finally received its new REST API!

Changes include:

- RDF data is now generated from a PostgreSQL/PostGIS database using the new SPARQL->SQL rewriter Sparqlify[1].
- Finally OSM relations are mapped!
- The Linked Data interface now based on Pubby (should rid content negotiation problems from the past)
- There is now a separation between Features and Geometries (See example links below)
- The ontology was cleaned up (but also changed)
- Links to the "Global Administrative Areas (GADM)"[2]
- Relations between classes and original OSM tags are retained using lgdm:sourceKey[3] and lgdm:sourceTag predicates.
- Data is from around Feb 1st 2012 and the Osmosis live sync is running. See [4] for a list of the 100 most current resources.

There are still some things to do:
- Right now the link to http://linkedgeodata.org/ontology is broken.
  For the time being, you can obtain it from http://downloads.linkedgeodata.org/LGD-Ontology.nt
- Some resources could still benefit from some data cleansing.
- Documentation of Sparqlify and the LGD schema additions to OSM needs to be improved. The goal is to enable anyone to set up their own LGD instance if they want.
- The old REST API has to be ported.

Suggestions and other feedback are much welcome!

Best regards,
Claus Stadler

Example Links
    The Eiffel Tower and its geometry:
        http://linkedgeodata.org/triplify/way5013364
        http://linkedgeodata.org/geometry/way5013364      (as geometry as a literal)
        http://linkedgeodata.org/geometry/posSeq5013364 (the geometry in modelled in RDF)

    The administrative boundary of Germany
        http://linkedgeodata.org/page/triplify/relation51477
        http://linkedgeodata.org/page/triplify/relation51477/members

    Leipzig
        http://linkedgeodata.org/page/triplify/node240111242

[1] Sparqlify
         Project Page: http://aksw.org/Projects/Sparqlify
         Source Code: https://github.com/AKSW/Sparqlify
         The Sparqlify configuration which is currently in use: https://github.com/AKSW/Sparqlify/blob/master/mappings/LinkedGeoData-Triplify-IndividualViews.sparqlify
         The schema additions (needs documentation): http://code.google.com/p/linkedgeodata/source/browse/trunk/3/src/main/sql

[2] Global Administrative Areas (GADM): http://gadm.geovocab.org/

[3] lgdm namespace: http://linkedgeodata.org/meta/

[4] http://linkedgeodata.org/status