Usefulness of ogd2_0_metadatenschema.json

In general technical (reference) implementations of semantic standards show how one would build the physical (technical) layer following agreements on the conceptual (semantical) layer.

The JSON file was created by Altova XML Spy "on the fly" based on the XSD file and serves the following non-normative purpose:

Exemplarly show the CKAN JSON people how the XML XSD structure would look like in JSON.

Nothing more, nothing less.

The OGD 2.0 Standard in its current "Entwurf" version does not impose one and only specific way how to implement the semantic agreements in the technical interoperability layer, but it gives suggestions and serves as examples.

There might also be RDF and other technical implementations of OGD.

If the German GovData federation stakeholder and other interested people will find the JSON file rather useless, overengineered or even errorprone, then we will delete it from the OGD 2.0 final standard "package".

I think knowing how OGD-2.0 metadata is encoded via JSON is very useful. However, I am not certain whether the current example cited above is actually helpful.

First of all, the JSON from the example was generated from XML and hence includes information like the XML declaration, which are of no use in a JSON-variant of the metadata. Instead, the example should be created directly for JSON, and not as a secondary thought from existing XML.

More important is the question whether we want a standardized way of encoding OGD-2.0 metadata in JSON. In my opinion that would be useful, for example in the form of a JSON Schema. However, if we decide not to do this then I would not add a JSON example to the standard. Obviously, JSON will be used in combination with OGD-2.0 so that use case has to be kept in mind. But, in my experience, examples of non-normative formats only lead to confusion.

If a JSON serialization is specified then it should conform to JSON-LD. A JSON-LD context then needs to be defined.

Our solution now follows the DCAT-AP approach. We created JSON and JSON schema as like as XML and XSD Schema to validate dcat-ap.de datasets. We even stripped down the German specifities as announced here: (Minute 5:09,DCAT-AP.de presentation at SEMIC 2017: https://www.youtube.com/watch?v=ZnVaI5cV13Q )

In addition we worked on rdf/xml validation with XSD while waiting for SHACL to become a W3C recommendation (now it is) and the DCAT-AP working group to have a SHACL file for June 2017 which we in future might extend to validate DCAT-AP.de.