Ejemplo n.º 1
0
def rewrite_sparql(query: str, context: Context) -> str:
    """Rewrite local property and type names from Model.template() as IRIs.

    Local names are mapped to IRIs by using a JSON-LD context, i.e. { "@context": { ... }} from a kgforge.core.commons.Context.
    In the case of contexts using prefixed names, prefixes are added to the SPARQL query prologue.
    In the case of non available contexts and vocab then the query is returned unchanged.
    """
    ctx = {
        k: v["@id"] if isinstance(v, Dict) else v
        for k, v in context.document["@context"].items()
    }
    prefixes = context.prefixes
    has_prefixes = prefixes is not None and len(prefixes.keys()) > 0
    if ctx.get("type") == "@type":
        if "rdf" in prefixes:
            ctx["type"] = "rdf:type"
        else:
            ctx["type"] = "http://www.w3.org/1999/02/22-rdf-syntax-ns#type"

    def replace(match: Match) -> str:
        m4 = match.group(4)
        if m4 is None:
            return match.group(0)
        else:
            v = ctx.get(
                m4, ":" +
                m4) if str(m4).lower() not in SPARQL_CLAUSES and not str(
                    m4).startswith("https") and context.has_vocab() else m4
            m5 = match.group(5)
            if "//" in v:
                return f"<{v}>{m5}"
            else:
                return f"{v}{m5}"

    g4 = r"([a-zA-Z_]+)"
    g5 = r"([.;]?)"
    g0 = rf"((?<=[\s,[(/|!^])((a|true|false)|{g4}){g5}(?=[\s,\])/|?*+]))"
    g6 = r"(('[^']+')|('''[^\n\r]+''')|(\"[^\"]+\")|(\"\"\"[^\n\r]+\"\"\"))"
    rx = rf"{g0}|{g6}|(?<=< )(.*)(?= >)"
    qr = re.sub(rx, replace, query, flags=re.VERBOSE)

    if not has_prefixes or "prefix" in str(qr).lower():
        return qr
    else:
        pfx = "\n".join(f"PREFIX {k}: <{v}>" for k, v in prefixes.items())
    if context.has_vocab():
        pfx = "\n".join([pfx, f"PREFIX : <{context.vocab}>"])
    return f"{pfx}\n{qr}"
Ejemplo n.º 2
0
def test_rewrite_sparql_unknownterm_missing_vocab(custom_context):
    context_object = Context(document=custom_context)
    assert not context_object.has_vocab()
    with pytest.raises(QueryingError):
        query = "SELECT ?x WHERE { Graph ?g { ?id propertyNotInContext/name/anotherPropertyNotInContext ?x }}"
        rewrite_sparql(query, context_object)