Validate the resource using its voluptuous schema

def validate(self):
        """Validate the resource using its voluptuous schema"""
        try:
            # update _resource to have default values from the schema
            self._resource = self.schema(self._resource)
        except MultipleInvalid as e:
            errors = [format_error(err, self.resource_type) for err in e.errors]
            raise exceptions.ValidationError({'errors': errors})

        yield self.check_unique()