Get extra metadata on datacubes

API:

  const entryPoint = new DataCubeEntryPoint(
    "https://trifid-lindas.test.cluster.ldbar.ch/query",
    {
      languages: ["fr", "de"],
      extraMetadata: [
        { variable: "contact", iri: "https://pcaxis.described.at/contact", multilang: true },
        { variable: "source", iri: "https://pcaxis.described.at/source", multilang: true },
        { variable: "survey", iri: "https://pcaxis.described.at/survey", multilang: true },
        { variable: "database", iri: "https://pcaxis.described.at/database", multilang: true },
        { variable: "unit", iri: "https://pcaxis.described.at/unit", multilang: true },
        { variable: "note", iri: "https://pcaxis.described.at/note", multilang: true },

        { variable: "dateCreated", iri: "http://schema.org/dateCreated", multilang: false },
        { variable: "dateModified", iri: "http://schema.org/dateModified", multilang: false },
        { variable: "temporalCoverage", iri: "http://schema.org/temporalCoverage", multilang: true },
        { variable: "description", iri: "http://www.w3.org/2000/01/rdf-schema#comment", multilang: true },
      ],
    },
  );

Resulting SPARQL:

PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
PREFIX qb: <http://purl.org/linked-data/cube#>
PREFIX dc11: <http://purl.org/dc/elements/1.1/>
PREFIX dcterms: <http://purl.org/dc/terms/>
PREFIX skos: <http://www.w3.org/2004/02/skos/core#>
SELECT ?iri ?graphIri ?label ?contact ?source ?survey ?database ?unit ?note ?dateCreated ?dateModified ?temporalCoverage ?description WHERE {
  GRAPH ?graphIri {
    ?iri rdf:type qb:DataSet.
    OPTIONAL {
      ?iri (rdfs:label|skos:prefLabel) ?label_fr.
      FILTER(LANGMATCHES(LANG(?label_fr), "fr"^^xsd:string))
    }
    OPTIONAL {
      ?iri (rdfs:label|skos:prefLabel) ?label_de.
      FILTER(LANGMATCHES(LANG(?label_de), "de"^^xsd:string))
    }
    OPTIONAL {
      ?iri <https://pcaxis.described.at/contact> ?contact_fr.
      FILTER(LANGMATCHES(LANG(?contact_fr), "fr"^^xsd:string))
    }
    OPTIONAL {
      ?iri <https://pcaxis.described.at/contact> ?contact_de.
      FILTER(LANGMATCHES(LANG(?contact_de), "de"^^xsd:string))
    }
    OPTIONAL {
      ?iri <https://pcaxis.described.at/source> ?source_fr.
      FILTER(LANGMATCHES(LANG(?source_fr), "fr"^^xsd:string))
    }
    OPTIONAL {
      ?iri <https://pcaxis.described.at/source> ?source_de.
      FILTER(LANGMATCHES(LANG(?source_de), "de"^^xsd:string))
    }
    OPTIONAL {
      ?iri <https://pcaxis.described.at/survey> ?survey_fr.
      FILTER(LANGMATCHES(LANG(?survey_fr), "fr"^^xsd:string))
    }
    OPTIONAL {
      ?iri <https://pcaxis.described.at/survey> ?survey_de.
      FILTER(LANGMATCHES(LANG(?survey_de), "de"^^xsd:string))
    }
    OPTIONAL {
      ?iri <https://pcaxis.described.at/database> ?database_fr.
      FILTER(LANGMATCHES(LANG(?database_fr), "fr"^^xsd:string))
    }
    OPTIONAL {
      ?iri <https://pcaxis.described.at/database> ?database_de.
      FILTER(LANGMATCHES(LANG(?database_de), "de"^^xsd:string))
    }
    OPTIONAL {
      ?iri <https://pcaxis.described.at/unit> ?unit_fr.
      FILTER(LANGMATCHES(LANG(?unit_fr), "fr"^^xsd:string))
    }
    OPTIONAL {
      ?iri <https://pcaxis.described.at/unit> ?unit_de.
      FILTER(LANGMATCHES(LANG(?unit_de), "de"^^xsd:string))
    }
    OPTIONAL {
      ?iri <https://pcaxis.described.at/note> ?note_fr.
      FILTER(LANGMATCHES(LANG(?note_fr), "fr"^^xsd:string))
    }
    OPTIONAL {
      ?iri <https://pcaxis.described.at/note> ?note_de.
      FILTER(LANGMATCHES(LANG(?note_de), "de"^^xsd:string))
    }
    OPTIONAL { ?iri <http://schema.org/dateCreated> ?dateCreated. }
    OPTIONAL { ?iri <http://schema.org/dateModified> ?dateModified. }
    OPTIONAL {
      ?iri <http://schema.org/temporalCoverage> ?temporalCoverage_fr.
      FILTER(LANGMATCHES(LANG(?temporalCoverage_fr), "fr"^^xsd:string))
    }
    OPTIONAL {
      ?iri <http://schema.org/temporalCoverage> ?temporalCoverage_de.
      FILTER(LANGMATCHES(LANG(?temporalCoverage_de), "de"^^xsd:string))
    }
    OPTIONAL {
      ?iri rdfs:comment ?description_fr.
      FILTER(LANGMATCHES(LANG(?description_fr), "fr"^^xsd:string))
    }
    OPTIONAL {
      ?iri rdfs:comment ?description_de.
      FILTER(LANGMATCHES(LANG(?description_de), "de"^^xsd:string))
    }
  }
  BIND(COALESCE(?label_fr, ?label_de, ""^^xsd:string) AS ?label)
  BIND(COALESCE(?contact_fr, ?contact_de, ""^^xsd:string) AS ?contact)
  BIND(COALESCE(?source_fr, ?source_de, ""^^xsd:string) AS ?source)
  BIND(COALESCE(?survey_fr, ?survey_de, ""^^xsd:string) AS ?survey)
  BIND(COALESCE(?database_fr, ?database_de, ""^^xsd:string) AS ?database)
  BIND(COALESCE(?unit_fr, ?unit_de, ""^^xsd:string) AS ?unit)
  BIND(COALESCE(?note_fr, ?note_de, ""^^xsd:string) AS ?note)
  BIND(COALESCE(?temporalCoverage_fr, ?temporalCoverage_de, ""^^xsd:string) AS ?temporalCoverage)
  BIND(COALESCE(?description_fr, ?description_de, ""^^xsd:string) AS ?description)
}

TODO:

[x] store and expose fetched extra metadata
[x] handle non-multilang metadata such as lastModified
[x] document the feature

related to #16

zazuko / query-rdf-data-cube

Get extra metadata on datacubes #30