Symfony 4 + JMS Serializer - Internal Server Error - api

Question

I have a problem with serialization data.
I have two entities, which are connection relation.
These are my entities:
Task.php
use Doctrine\ORM\Mapping as ORM;
use JMS\Serializer\Annotation as JMS;
/**
* #ORM\Entity
*/
class Task
{
/**
*
* #var integer
*
* #ORM\Id
* #ORM\Column(type="integer")
* #ORM\GeneratedValue(strategy="IDENTITY")
*
*/
private $id;
/**
* #JMS\MaxDepth(1)
* #ORM\ManyToOne(targetEntity="App\Entity\User", inversedBy="task")
*
*/
private $user;
User.php
use FOS\UserBundle\Model\User as BaseUser;
use Doctrine\ORM\Mapping as ORM;
/**
* #ORM\Entity
* #ORM\Table(name="app_user")
*/
class User extends BaseUser
{
/**
* #ORM\Id
* #ORM\Column(type="integer")
* #ORM\GeneratedValue(strategy="AUTO")
*/
protected $id;
/**
* #ORM\OneToMany(targetEntity="App\Entity\Task", mappedBy="user")
*/
private $task;
public function __construct()
{
I would like to create API, and I serialization my data with JMS. I get this error:
Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
This is my controller:
public function getAllAction(): JsonResponse
{
$tasks = $this->taskService->getAll();
$serializer = SerializerBuilder::create()->build();
$data = $serializer->serialize($tasks, 'json',
SerializationContext::create()->enableMaxDepthChecks());
return new JsonResponse($data, 200, [], true);
}
Function getAll in my controller return data with table Task.
Please, help me with my problem. :)
Thanks, Friends.

Answer 1

I did not use JMS Serializer but i can suggest different solution like symfony serializer component.
public function getAllAction(SerializerInterface $serializer): JsonResponse
{
$data = $serializer->serialize($this->taskService->getAll(), 'json');
return new JsonResponse($data, 200, [], true);
}
Optional you can set serialization group to avoid circular reference error.
For each entity atribute that you want to serialize, set:
use Symfony\Component\Serializer\Annotation\Groups;
/**
* #ORM\Column(name="title", type="string", nullable=false, length=150)
* #Assert\Type("string")
* #Assert\NotBlank()
* #Groups({"group_name"})
*/
private $title;
/**
* #ORM\Column(name="description", type="string", nullable=true, length=255)
* #Assert\Type("string")
*/
private $description;
And then you serialize only this field with specific group:
$serializer->serialize($this->taskService->getAll(), 'json', ['groups' => ['group_name']])
Doc: https://symfony.com/doc/4.1/serializer.html#using-serialization-groups-annotations
PS. Action suffix isnt required now
https://symfony.com/doc/current/best_practices/controllers.html#controller-action-naming