Pimcore\Model\Object\ClassDefinition\Data\Href::getDataForResource PHP Method

    public function getDataForResource($data, $object = null, $params = [])
    {
        if ($data instanceof Element\ElementInterface) {
            $type = Element\Service::getType($data);
            $id = $data->getId();
            return [["dest_id" => $id, "type" => $type, "fieldname" => $this->getName()]];
        } else {
            return null;
        }
    }