How to add an Ontology IRI with the Python rdflib library?

Question

My problem is described here but the (maybe old) proposed solution does not work for me!

https://github.com/RDFLib/rdflib/issues/817

I would like to use rdflib to fill with Python the Ontology IRI like in the Ontology header of Protégé.

Answer 1

I am not sure what you mean by an ontology header. I'm assuming you want to programmatically modify the ontology metadata. The following code adds a few statements. You can use the add() and remove() methods on the graph object as shown below to alter your data.

from rdflib import OWL, RDF, RDFS, Graph, URIRef, Literal

g = Graph()

ontology_iri = URIRef("urn:example:ontology_iri")

g.add((ontology_iri, RDF.type, OWL.Ontology))
g.add((ontology_iri, RDFS.label, Literal("My ontology")))

g.print()

Output:

@prefix owl: <http://www.w3.org/2002/07/owl#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .

<urn:example:ontology_iri> a owl:Ontology ;
    rdfs:label "My ontology" .

Answer 2

A new solution from here : https://github.com/RDFLib/rdflib/issues/817

from rdflib.extras.infixowl import Ontology

baseuri = rdflib.URIRef("http://purl.org/net/bel-epa/polti.owl")
nsuri = rdflib.URIRef(str(baseuri) + '#')
POLTI = rdflib.Namespace(nsuri)

g = rdflib.Graph(identifier=baseuri)
g.bind('polti', POLTI)

o = Ontology(
    identifier=nsuri,
    graph=g,
    comment=rdflib.Literal(
        "Georges Polti‘s Thirty-Six Dramatic Situations.", lang="en"
    ),
)
o.setVersion(rdflib.Literal("0.1.0", lang="en"))
print(g.serialize(format='pretty-xml'))

Output:

<?xml version="1.0" encoding="utf-8"?>
<rdf:RDF
  xmlns:owl="http://www.w3.org/2002/07/owl#"
  xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
>
  <owl:Ontology rdf:about="http://purl.org/net/bel-epa/polti.owl#">
    <rdfs:comment xml:lang="en">Georges Polti‘s Thirty-Six Dramatic Situations.</rdfs:comment>
    <owl:versionInfo xml:lang="en">0.1.0</owl:versionInfo>
  </owl:Ontology>
</rdf:RDF>