sparqlstore.py 文件源码

def _node_from_result(node):
    """
    Helper function that casts XML node in SPARQL results
    to appropriate rdflib term
    """
    if node.tag == '{%s}bnode' % SPARQL_NS:
        return BNode(node.text)
    elif node.tag == '{%s}uri' % SPARQL_NS:
        return URIRef(node.text)
    elif node.tag == '{%s}literal' % SPARQL_NS:
        value = node.text if node.text is not None else ''
        if 'datatype' in node.attrib:
            dt = URIRef(node.attrib['datatype'])
            return Literal(value, datatype=dt)
        elif '{http://www.w3.org/XML/1998/namespace}lang' in node.attrib:
            return Literal(value, lang=node.attrib[
                "{http://www.w3.org/XML/1998/namespace}lang"])
        else:
            return Literal(value)
    else:
        raise Exception('Unknown answer type')