Symfony Serializer：精确控制关联实体属性的序列化

// src/Entity/User.php
namespace App\Entity;

use Doctrine\Common\Collections\ArrayCollection;
use Doctrine\Common\Collections\Collection;
use Doctrine\ORM\Mapping as ORM;

/**
 * @ORM\Entity
 * @ORM\Table(name="`user`") // 注意：user是SQL保留字，通常需要加反引号或重命名
 */
class User
{
    /**
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     * @ORM\Column(type="integer")
     */
    private $id;

    /**
     * @ORM\Column(type="string", length=255)
     */
    private $name;

    /**
     * @ORM\ManyToMany(targetEntity=Post::class)
     */
    private $posts;

    public function __construct()
    {
        $this->posts = new ArrayCollection();
    }

    public function getId(): ?int
    {
        return $this->id;
    }

    public function getName(): ?string
    {
        return $this->name;
    }

    public function setName(string $name): self
    {
        $this->name = $name;
        return $this;
    }

    /**
     * @return Collection<int, Post>
     */
    public function getPosts(): Collection
    {
        return $this->posts;
    }

    public function addPost(Post $post): self
    {
        if (!$this->posts->contains($post)) {
            $this->posts[] = $post;
        }
        return $this;
    }

    public function removePost(Post $post): self
    {
        $this->posts->removeElement($post);
        return $this;
    }
}

// src/Entity/Post.php
namespace App\Entity;

use Doctrine\ORM\Mapping as ORM;

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

    /**
     * @ORM\Column(type="string", length=255)
     */
    private $content;

    public function getId(): ?int
    {
        return $this->id;
    }

    public function getContent(): ?string
    {
        return $this->content;
    }

    public function setContent(string $content): self
    {
        $this->content = $content;
        return $this;
    }
}

{
    "id": 79,
    "name": "User 1",
    "posts": [
      {
        "id": 73
      },
      {
        "id": 74
      }
    ]
}

# config/serializer/Post.yaml
App\Entity\Post:
    attributes:
        id:
            groups: ['post:read'] # 可以选择性地添加组，或者不添加
        content:
            ignore: true # 明确忽略content属性

// src/Entity/Post.php
namespace App\Entity;

use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Serializer\Annotation\Ignore; // 引入Ignore注解

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

    /**
     * @ORM\Column(type="string", length=255)
     * @Ignore // 使用Ignore注解忽略此属性
     */
    private $content;

    // ... 其他方法
}

// src/Entity/User.php
namespace App\Entity;

use Doctrine\Common\Collections\ArrayCollection;
use Doctrine\Common\Collections\Collection;
use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Serializer\Annotation\Groups; // 引入Groups注解

/**
 * @ORM\Entity
 * @ORM\Table(name="`user`")
 */
class User
{
    /**
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     * @ORM\Column(type="integer")
     * @Groups({"user:read", "post:read_user_summary"}) // 为id添加组
     */
    private $id;

    /**
     * @ORM\Column(type="string", length=255)
     * @Groups({"user:read"}) // 为name添加组
     */
    private $name;

    /**
     * @ORM\ManyToMany(targetEntity=Post::class)
     * @Groups({"user:read"}) // 为posts集合添加组
     */
    private $posts;

    // ... 构造函数和getter/setter
}

// src/Entity/Post.php
namespace App\Entity;

use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Serializer\Annotation\Groups; // 引入Groups注解

/**
 * @ORM\Entity
 */
class Post
{
    /**
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     * @ORM\Column(type="integer")
     * @Groups({"post:read", "user:read"}) // 为id添加组，使其在user:read组中可见
     */
    private $id;

    /**
     * @ORM\Column(type="string", length=255)
     * @Groups({"post:read"}) // 只有在post:read组中才序列化content
     */
    private $content;

    // ... getter/setter
}

<?php
// 例如在一个Controller中

namespace App\Controller;

use App\Entity\User;
use App\Entity\Post;
use Doctrine\ORM\EntityManagerInterface;
use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\HttpFoundation\JsonResponse;
use Symfony\Component\Routing\Annotation\Route;
use Symfony\Component\Serializer\SerializerInterface;

class UserController extends AbstractController
{
    /**
     * @Route("/users/{id}", name="get_user", methods={"GET"})
     */
    public function getUserDetails(
        int $id,
        EntityManagerInterface $entityManager,
        SerializerInterface $serializer
    ): JsonResponse {
        $user = $entityManager->getRepository(User::class)->find($id);

        if (!$user) {
            throw $this->createNotFoundException('User not found');
        }

        // 序列化User对象，并指定激活'user:read'组
        // 这将导致User的id、name和posts集合被序列化。
        // 对于posts集合中的每个Post，由于Post的id也属于'user:read'组，所以id会被序列化。
        // 而Post的content只属于'post:read'组，因此不会被序列化。
        $jsonContent = $serializer->serialize($user, 'json', ['groups' => ['user:read']]);

        return new JsonResponse($jsonContent, 200, [], true);
    }
}