filters.py 文件源码

def is_valid_field(self, model, field):
        # Split with maximum splits of 1, so if passed xx__yy__zz, we get [xx, yy__zz]
        components = field.split(LOOKUP_SEP, 1)
        try:
            field = model._meta.get_field(components[0])

            # Reverse lookup
            if isinstance(field, ForeignObjectRel):
                return self.is_valid_field(field.model, components[1])

            if field.get_internal_type() in self.related_field_types and len(components) > 1:
                return self.is_valid_field(field.related_model, components[1])

            return True
        except FieldDoesNotExist:
            return False