使用ManyToMany关系序列化学说对象

Question

I'm trying to serialize object to json by following symfony official docs. I'v got Pagerfanta object(getting it from repository just like in Demo Application)

    public function findOneIncRel(int $page = 1): Pagerfanta
    {
        $query = $this->createQueryBuilder('b')
            ->select('b, m, a')
            ->leftJoin('b.marks', 'm')
            ->leftJoin('b.authors', 'a')
            ->getQuery();
        return $this->createPaginator($query, $page);
    }

    private function createPaginator(Query $query, int $page): Pagerfanta
    {
        $paginator = new Pagerfanta(new DoctrineORMAdapter($query));
        $paginator->setMaxPerPage(10);
        $paginator->setCurrentPage($page);

        return $paginator;
    }

I need to turn result into JSON.

I'v tried this:

$books = $bookRepository->findAllIncRel(1);
$encoder = array(new JsonEncoder());
$normalizers = array(new ObjectNormalizer());
$normalizers[0]->setCircularReferenceLimit(1);
$normalizers[0]->setCircularReferenceHandler(function ($object) {
    return $object->getId();
});
$serializer = new Serializer($normalizers, $encoder);
return new JsonResponse($serializer->serialize($books->getCurrentPageResults(), 'json'));

Structure of instance of Book is like this:

-id: ...
-marks: PersistentCollection ...
-authors: PersistentCollection ...
...

But all I'v got are uncatchable 500 error or "Maximum execution time of 30 seconds exceeded" I don't know what is problem here. Is there some other way to serialize PagerFanta object?

Best regards!

Answer 1

答案非常简单-我没有使用循环引用处理程序，而是使用$normalizer->setIgnoredAttributes(array(...related fields of 2nd level objects...))