VariationCartNormalizer.php with whitelisted fields for response

VariationCartNormalizer.php

<?php

namespace Drupal\my_commerce\Normalizer;

use Drupal\commerce_product\Entity\ProductVariationInterface;
use Drupal\Core\TypedData\TypedDataInternalPropertiesHelper;
use Drupal\serialization\Normalizer\NormalizerBase;

/**
 * Converts typed data objects to arrays.
 */
class VariationCartNormalizer extends NormalizerBase {

  private $whitelistFields = [
    'price',
    'title',
    'variation_id',
    'product_id',
    'uuid',
  ];

  /**
   * The interface or class that this Normalizer supports.
   *
   * @var string
   */
  protected $supportedInterfaceOrClass = ProductVariationInterface::class;

  /**
   * {@inheritdoc}
   */
  public function normalize($entity, $format = NULL, array $context = []) {
    $context += [
      'account' => NULL,
    ];

    $attributes = [];
    foreach (TypedDataInternalPropertiesHelper::getNonInternalProperties($entity->getTypedData()) as $name => $field_items) {
      if (in_array($name, $this->whitelistFields)) {
        if ($field_items->access('view', $context['account'])) {
          $attributes[$name] = $this->serializer->normalize($field_items, $format, $context);
        }
      }
    }

    return $attributes;
  }
}