symfony 3 doctrine one to one uni-direction returning unwanted fields when querying

Question

I have got two classes which are being associated using one to one uni-direction

{
 id: 1,
 name: "onetooneuniparent name",
 onetooneunichild: {
   id: 1,
   name: "onetooneunichild name",
   __initializer__: null,
   __cloner__: null,
   __isInitialized__: true
  }
}

the above is the result when I do query like following

http://localhost:8000/onetooneRead?id=1

I want to know where and why the following come from

__initializer__: null,
__cloner__: null,
__isInitialized__: true

my expected result is just this

{
 id: 1,
 name: "onetooneuniparent name",
 onetooneunichild: {
   id: 1,
   name: "onetooneunichild name"
  }
}

OnetoOneUniParent.php

namespace AppBundle\Entity;

use Doctrine\ORM\Mapping as ORM;

/**
 * @ORM\Entity
 * @ORM\Table(name="onetooneuniparent")
 */

class OnetoOneUniParent{

/**
 * @ORM\Column(type="integer")
 * @ORM\Id
 * @ORM\GeneratedValue(strategy="AUTO")
 */
private $id;

/**
 * @ORM\Column(type="string",name="name")    
 */
private $name;

/**  
 * @ORM\OneToOne(targetEntity="OnetoOneUniChild",cascade={"persist"})
 * @ORM\JoinColumn(name="child_id", referencedColumnName="id")
 */
private $onetooneunichild;

<.... getter and setter here ...>
}

OnetoOneUniChild.php

namespace AppBundle\Entity;

use Doctrine\ORM\Mapping as ORM;

/**
 * @ORM\Entity
 * @ORM\Table(name="onetooneunichild")
 */
 class OnetoOneUniChild{

/**
 * @ORM\Column(type="integer")
 * @ORM\Id
 * @ORM\GeneratedValue(strategy="AUTO")
 */
private $id;

/**
 * @ORM\Column(type="string",name="name")    
 */
private $name;

<.... getter and setter here ...>

This is the method in controller

/**
 * @Route("/onetooneRead")
 * @Method("GET")
 */
public function onetooneReadAction(Request $request){
    $logger = $this->get('logger');
    $encoders = array(new XmlEncoder(), new JsonEncoder());
    $normalizers = array(new ObjectNormalizer());

    $serializer = new Serializer($normalizers, $encoders);

    $logger->info('onetoone Read');

    $id = $request->query->get("id");

    $em = $this->getDoctrine()->getManager();
    $onetooneuniparent = $em->getRepository('AppBundle:OnetoOneUniParent')->find($id);

    $onetooneuniparentJson = $serializer->serialize($onetooneuniparent, 'json');

    $response = new JsonResponse();

    $response->setContent($onetooneuniparentJson);

    return $response;   
}

This is what is inside in MySQL

mysql> select * from onetooneuniparent;
+----+----------+------------------------+
| id | child_id | name                   |
+----+----------+------------------------+
|  1 |        1 | onetooneuniparent name |
|  2 |        2 | onetooneuniparent name |
|  3 |        3 | onetooneuniparent name |
+----+----------+------------------------+
3 rows in set (0.00 sec)

mysql> select * from onetooneunichild;
+----+-----------------------+
| id | name                  |
+----+-----------------------+
|  1 | onetooneunichild name |
|  2 | onetooneunichild name |
|  3 | onetooneunichild name |
+----+-----------------------+
3 rows in set (0.00 sec)

Answer 1

Those functions are part of the Doctrine proxy coding, since you are using Lazy Loading Doctrine needs to keep track of the child entity if it needs to be loaded or not. Part of that keeping track is these functions (I believe it is in this portion of Doctrine)

There may be a way around this which would be to avoid using lazy loading. To do that you can utilize EAGER loading if you always want the child to load with the parent. Alternatively if you only want to use EAGER for this one query and not every time you would have to switch to DQL as documented here or you could use the JOIN comma (second example down) here