Check the ability to load to GraphDB (both SPARQL and Graph Store Protocol)

[jakubklimek]

we need to verify the ability of our loading components to load to Ontotext GraphDB. The SPARQL update loader failed to load to our graphdb instance and in #685 it seems that graphstoreprotocol loader is not able to load to graphdb either.

[schivmeister]

Hi @jakubklimek, if we are to understand right, we are still unable to write (load an RDF file, for example) to GraphDB at this time? That is, the Graph store protocol, SPARQL endpoint loader and SPARQL endpoint loader chunked components are unusable? Is there an alternative (for loading an RDF file or statements) for GraphDB, then?

[jakubklimek]

@schivmeister Actually, we do use Graph store protocol with GraphDB, so that one definitely works. SPARQL endpoint loader and loader chunked should work as well, even though I do not have a running instance of that anywhere.

[schivmeister]

Thanks @jakubklimek, I was thrown off course by not being able to find the right format for the parameters, especially protocol endpoint. After consulting the Graph Store spec, GraphDB's documentation, and the ETL code for uploadGraphDB, it became apparent that the URL scheme is https://{baseUrl}/repositories/{repo}/rdf-graphs/service.

Additionally, authentication should be turned ON (read access doesn't always mean public access) and most deployments with SSL/TLS will now have a hard redirect on non-HTTPS URLs, requiring the protocol URL to be with https, yielding a 302 response otherwise.

It would be good to document this somewhere. I see the only examples/tutorials are for Fuseki and Virtuoso, both of which have different protocol connection URL schemes, as the implementation of the Graph Store protocol is vendor-dependent.