SerializationTestNormalizer.php

<?php

namespace Drupal\serialization_test;

use Symfony\Component\Serializer\Normalizer\NormalizerInterface;
class SerializationTestNormalizer implements NormalizerInterface {
    
    /**
     * The format that this Normalizer supports.
     *
     * @var string
     */
    protected static $format = 'serialization_test';
    
    /**
     * {@inheritdoc}
     */
    public function normalize($object, $format = NULL, array $context = []) : array|string|int|float|bool|\ArrayObject|null {
        $normalized = (array) $object;
        // Add identifying value that can be used to verify that the expected
        // normalizer was invoked.
        $normalized['normalized_by'] = 'SerializationTestNormalizer';
        return $normalized;
    }
    
    /**
     * {@inheritdoc}
     */
    public function supportsNormalization($data, ?string $format = NULL, array $context = []) : bool {
        return static::$format === $format;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getSupportedTypes(?string $format) : array {
        return [
            \stdClass::class => TRUE,
        ];
    }

}