RDF Parser

Bases: Parser

Parsers RDF Graphs into typedlogic theories.

Example:

>>> parser = RDFParser()
>>> import rdflib as rdflib
>>> from rdflib.namespace import RDF, RDFS
>>> g = rdflib.Graph()
>>> EX = rdflib.Namespace("http://example.org/")
>>> _ = g.add((EX.hasPet, RDFS.domain, EX.Human))
>>> _ = g.add((EX.hasPet, RDFS.range, EX.Animal))
>>> _ = g.add((EX.Fred, EX.hasPet, EX.Fido))
>>> theory = parser.parse(g)
>>> preds = [pd.predicate for pd in theory.predicate_definitions]
>>> for pred in sorted(preds):
...     print(pred)
<BLANKLINE>
...
SubClassOf
SubPropertyOf
Triple
...

Note that the predicates here are predicates from the theory of RDF, RDFS, and OWL-Full. "user-defined" predicates (e.g. hasPet) are not in this list, as these are mapped to instances of Triple.

>>> facts = [fact.as_sexpr() for fact in theory.ground_terms]
>>> for fact in sorted(facts):
...     print(fact)
['Triple', rdflib.term.URIRef('http://example.org/Fred'), rdflib.term.URIRef('http://example.org/hasPet'), rdflib.term.URIRef('http://example.org/Fido')]
['Triple', rdflib.term.URIRef('http://example.org/hasPet'), rdflib.term.URIRef('http://www.w3.org/2000/01/rdf-schema#domain'), rdflib.term.URIRef('http://example.org/Human')]
['Triple', rdflib.term.URIRef('http://example.org/hasPet'), rdflib.term.URIRef('http://www.w3.org/2000/01/rdf-schema#range'), rdflib.term.URIRef('http://example.org/Animal')]

After this other facts can be inferred using a solver.

>>> from typedlogic.registry import get_solver
>>> s = get_solver("souffle")
>>> s.add(theory)
>>> model = s.model()
>>> assert model
>>> from typedlogic.integrations.frameworks.rdflib.rdfs import Type
>>> for fact in sorted(model.retrieve(Type)):
...     print(fact)
Type(http://example.org/Fido, http://example.org/Animal)
Type(http://example.org/Fred, http://example.org/Human)

Source code in src/typedlogic/integrations/frameworks/rdflib/rdf_parser.py

class RDFParser(Parser):
    """
    Parsers RDF Graphs into typedlogic theories.

    Example:

        >>> parser = RDFParser()
        >>> import rdflib as rdflib
        >>> from rdflib.namespace import RDF, RDFS
        >>> g = rdflib.Graph()
        >>> EX = rdflib.Namespace("http://example.org/")
        >>> _ = g.add((EX.hasPet, RDFS.domain, EX.Human))
        >>> _ = g.add((EX.hasPet, RDFS.range, EX.Animal))
        >>> _ = g.add((EX.Fred, EX.hasPet, EX.Fido))
        >>> theory = parser.parse(g)
        >>> preds = [pd.predicate for pd in theory.predicate_definitions]
        >>> for pred in sorted(preds):
        ...     print(pred)
        <BLANKLINE>
        ...
        SubClassOf
        SubPropertyOf
        Triple
        ...

    Note that the predicates here are predicates from the theory of RDF, RDFS, and OWL-Full.
    "user-defined" predicates (e.g. hasPet) are not in this list, as these are mapped to instances
    of Triple.

        >>> facts = [fact.as_sexpr() for fact in theory.ground_terms]
        >>> for fact in sorted(facts):
        ...     print(fact)
        ['Triple', rdflib.term.URIRef('http://example.org/Fred'), rdflib.term.URIRef('http://example.org/hasPet'), rdflib.term.URIRef('http://example.org/Fido')]
        ['Triple', rdflib.term.URIRef('http://example.org/hasPet'), rdflib.term.URIRef('http://www.w3.org/2000/01/rdf-schema#domain'), rdflib.term.URIRef('http://example.org/Human')]
        ['Triple', rdflib.term.URIRef('http://example.org/hasPet'), rdflib.term.URIRef('http://www.w3.org/2000/01/rdf-schema#range'), rdflib.term.URIRef('http://example.org/Animal')]

    After this other facts can be inferred using a solver.

        >>> from typedlogic.registry import get_solver
        >>> s = get_solver("souffle")
        >>> s.add(theory)
        >>> model = s.model()
        >>> assert model
        >>> from typedlogic.integrations.frameworks.rdflib.rdfs import Type
        >>> for fact in sorted(model.retrieve(Type)):
        ...     print(fact)
        Type(http://example.org/Fido, http://example.org/Animal)
        Type(http://example.org/Fred, http://example.org/Human)

    """

    def parse(self, source: Union[Path, str, TextIO, Graph], format="ttl", **kwargs) -> Theory:
        """
        Parse am RDF Graph to a theory.

        :param source: rdflib Graph pr a path to a graph
        :param format: rdflib accepted format
        :param kwargs:
        :return: Parsed theory
        """
        if isinstance(source, Graph):
            g = source
        else:
            g = Graph()
            g.parse(source, format=format)
        parser = PythonParser()
        theory = parser.transform(rdfs)
        for sentence in rdf.generate_sentences(g):
            t = sentence.to_model_object()
            if not isinstance(t, Term):
                raise ValueError(f"expected term: {t}")
            theory.ground_terms.append(t)
        return theory

parse(source, format='ttl', **kwargs)

Parse am RDF Graph to a theory.

Parameters:

Name	Type	Description	Default
source	Union[Path, str, TextIO, Graph]	rdflib Graph pr a path to a graph	required
format		rdflib accepted format	'ttl'
kwargs			{}

Returns:

Type	Description
Theory	Parsed theory

Source code in src/typedlogic/integrations/frameworks/rdflib/rdf_parser.py

def parse(self, source: Union[Path, str, TextIO, Graph], format="ttl", **kwargs) -> Theory:
    """
    Parse am RDF Graph to a theory.

    :param source: rdflib Graph pr a path to a graph
    :param format: rdflib accepted format
    :param kwargs:
    :return: Parsed theory
    """
    if isinstance(source, Graph):
        g = source
    else:
        g = Graph()
        g.parse(source, format=format)
    parser = PythonParser()
    theory = parser.transform(rdfs)
    for sentence in rdf.generate_sentences(g):
        t = sentence.to_model_object()
        if not isinstance(t, Term):
            raise ValueError(f"expected term: {t}")
        theory.ground_terms.append(t)
    return theory