This extension provides plugins that allow CKAN to expose and consume metadata from other catalogs using documents serialized using DCAT. The Data Catalog Vocabulary (DCAT) is "an RDF vocabulary designed to facilitate interoperability between data catalogs published on the Web". More information can be found on the following W3C page:
http://www.w3.org/TR/vocab-dcat/
NOTE: Both this extension and the serializations and protocol are a work in progress. All comments are welcome, just create an issue on the GitHub repository or send an email to the CKAN discussion list:
http://lists.okfn.org/mailman/listinfo/ckan-discuss
With the emergence of Open Data initiatives around the world, the need to share metadata across different catalogs has became more evident. Sites like http://publicdata.eu aggregate datasets from different portals, and there has been a growing demand to provide a clear and standard interface to allow incorporating metadata into them automatically.
There is growing consensus around DCAT being the right way forward, but an actual implementation is needed. In designing the following guidelines, the main requirement has been in all cases to keep it extremely simple, making as easy as possible for catalogs to implement them.
This extension offers the following Implementation Guidelines:
- A serialization format for dataset metadata in RDF/XML and JSON format, both based on standard DCAT properties.
- A simple mechanism for exposing a catalog metadata dumps, with optional methods for pagination and filtering.
In terms of CKAN, this extension offers:
- TODO: Endpoints for (paginated) dumps of all the catalog's datasets metadata in RDF/XML and JSON format.
- TODO: Individual endpoints for describing a dataset metadata in RDF/XML and JSON format. (Note: CKAN core already offers a RDF/XML representation, need to decide hwo they fit together).
- Harvesters that allow importing similar dumps in RDF/XML or JSON from other catalogs to create CKAN datasets.