Symfony Serializer: deserializing JSON to DTO example

symfony-deserialize-json-to-dto.php

<?php

require 'vendor/autoload.php';

use Symfony\Component\PropertyInfo\Extractor\ConstructorExtractor;
use Symfony\Component\PropertyInfo\Extractor\PhpDocExtractor;
use Symfony\Component\PropertyInfo\PropertyInfoExtractor;
use Symfony\Component\Serializer\Encoder\JsonEncoder;
use Symfony\Component\Serializer\Normalizer\ArrayDenormalizer;
use Symfony\Component\Serializer\Normalizer\ObjectNormalizer;
use Symfony\Component\Serializer\Serializer;

class UserDTO {
    /**
     * @param AddressDTO[] $addressBook
     */
    public function __construct(
        public string $name,
        public int $age,
        public ?AddressDTO $billingAddress,
        public ?AddressDTO $shippingAddress,
        public array $addressBook,
    ) {
    }
}

class AddressDTO {
    public function __construct(
        public string $street,
        public string $city,
    ) {
    }
}

function deserialize(string $json, string $className): object
{
    $phpDocExtractor = new PhpDocExtractor();
    $typeExtractor = new PropertyInfoExtractor(
        typeExtractors: [
            new ConstructorExtractor([$phpDocExtractor]),
            $phpDocExtractor,
        ],
    );

    $normalizers = [
        new ObjectNormalizer(propertyTypeExtractor: $typeExtractor),
        new ArrayDenormalizer(),
    ];

    $encoders = [
        new JsonEncoder(),
    ];

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

    return $serializer->deserialize($json, $className, 'json');
}

$json = '
    {
      "name": "John",
      "age": 25,
      "billingAddress": {
        "street": "Rue Paradis",
        "city": "Marseille"
      },
      "shippingAddress": null,
      "addressBook": [
        {
          "street": "Rue Paradis",
          "city": "Marseille"
        }
      ]
    }
';

dd(deserialize($json, UserDTO::class));