feat(RDF): Email/UUID should now be an IRI instead of String (+ code maintenance for easier implementation)

[svandenhoek]

What are the main changes you did:

• Improved code (readability):
  • Default namespaces moved to their own Enum
  • CoreDatatype retrieval & formatValue(row, column) moved to a class dedicated for ColumnType-specific behaviour.
    • Reduced duplicate code while streaming the cell data during conversion to Value.
    • This approach should allow for same CoreDataType with different cell data retrieval without needing the 2-layer approach currently implemented through formatValue() (first layer differentiates references/FILE/others & second layer for others defines 1 basic approach per CoreDataType)
    • Includes a SKIP internal type to allow for specific ColumnType values to always return an emtpy Set
  • rowsToRdf() split into separate functions for ontologies/data TableType.
    • Adjusted logics where a TableType check was done for each Row instead of for each Table.
• Added a test that validates there is RDF conversion logics available for each ColumnType
  • Code should fail to build if existing ColumnType is removed
  • Test should fail if new ColumnType is added without updating the RDF API for it.
• Fixes fix(rdf): Email addresses should be IRIs, not literals #4226
• UUIDs should now be urn:uuid: IRIs instead of literals
• Fixes ColumnType.FILE not being present in RDF output (+ updated to show correct path)
• In theory should make future implementations for the following easier:
  • new column type: telephone number #4224
  • RDF API: For semantics-output, ontologies should use ontologyTermURI instead #4222

how to test:

1. Checkout master
2. ./gradlew run
3. Create DCAT DB with demo data
4. curl http://localhost:8080/dcat/api/rdf > ~/Desktop/output_old.ttl
5. Checkout PR
6. ./gradlew run
7. curl http://localhost:8080/dcat/api/rdf > ~/Desktop/output_new.ttl
8. (Apache Jena CMD tools) rdfdiff output_new.ttl output_old.ttl TTL TTL
   Output should look like this (only unequal in regards to changes made to email):

$ rdfdiff output_new.ttl output_old.ttl TTL TTL
models are unequal

< [http://localhost:8080/dcat/api/rdf/ContactPersons?identifier=Person01, http://semanticscience.org/resource/SIO_001323, mailto:[email protected]]
< [http://localhost:8080/dcat/api/rdf/ContactPersons?identifier=Person01, http://localhost:8080/dcat/api/rdf/ContactPersons/column/email, mailto:[email protected]]
< [http://localhost:8080/dcat/api/rdf/ContactPersons?identifier=Person01, http://purl.obolibrary.org/obo/NCIT_C42775, mailto:[email protected]]
< [http://localhost:8080/dcat/api/rdf/ContactPersons/column/email, http://www.w3.org/2000/01/rdf-schema#range, http://www.w3.org/2001/XMLSchema#anyURI]
> [http://localhost:8080/dcat/api/rdf/ContactPersons?identifier=Person01, http://localhost:8080/dcat/api/rdf/ContactPersons/column/email, [email protected]]
> [http://localhost:8080/dcat/api/rdf/ContactPersons?identifier=Person01, http://semanticscience.org/resource/SIO_001323, [email protected]]
> [http://localhost:8080/dcat/api/rdf/ContactPersons?identifier=Person01, http://purl.obolibrary.org/obo/NCIT_C42775, [email protected]]
> [http://localhost:8080/dcat/api/rdf/ContactPersons/column/email, http://www.w3.org/2000/01/rdf-schema#range, http://www.w3.org/2001/XMLSchema#string]

Turtle output should now look something like this:

[...]

sio:SIO_001323 <mailto:[email protected]>;
  <http://purl.obolibrary.org/obo/NCIT_C42775> <mailto:[email protected]>;
  <http://localhost:8080/dcat/api/rdf/ContactPersons/column/email> <mailto:[email protected]>;

[...]

<http://localhost:8080/dcat/api/rdf/ContactPersons/column/email> a owl:DatatypeProperty;
  rdfs:range "http://www.w3.org/2001/XMLSchema#anyURI";

[...]

todo:

• updated docs in case of new feature
• added/updated tests
• added/updated testplan to include a test for this fix, including ref to bug using # notation

[sonarcloud]

Quality Gate passed

Issues
10 New issues
0 Accepted issues

Measures
0 Security Hotspots
91.2% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[svandenhoek]

All tests should work once #4378 is merged and included in this branch.