Virtuoso helper for SPARQLWrapper 1.6.0

virtuoso.py

from SPARQLWrapper import SPARQLWrapper


class VirtuosoWrapper(SPARQLWrapper):
    def setParameter(self, name, value):
        self.clearParameter(name)
        return self.addParameter(name, value)

    def setReturnFormat(self, output_format):
        if output_format == 'jsonld':
            self.returnFormat = 'jsonld'
        else:
            super().setReturnFormat(output_format)

    def _virtuoso_output_format(self):
        if self.queryType in ['SELECT', 'ASK', 'INSERT', 'DELETE', 'MODIFY']:
            if self.returnFormat == 'xml':
                output_format = b'application/sparql-results+xml'
            elif self.returnFormat == 'json':
                output_format = b'application/sparql-results+json'
            else:
                output_format = b'application/sparql-results+json'
        else:
            if self.returnFormat == 'n3' or self.returnFormat == 'turtle':
                output_format = b'text/turtle'
            elif self.returnFormat == 'xml':
                output_format = b'application/xml+rdf'
            elif self.returnFormat == 'jsonld':
                output_format = b'application/x-json+ld'
            else:
                output_format = b'application/x-json+ld'

        return output_format

    def _getRequestParameters(self):
        parameters = super()._getRequestParameters()

        for param in ["format", "output", "results"]:
            parameters.pop(param, None)

        parameters[b"format"] = self._virtuoso_output_format()

        return parameters