ComputedTestCacheableIntegerItemList.php

<?php

namespace Drupal\entity_test\Plugin\Field;

use Drupal\Core\Cache\CacheableDependencyInterface;
use Drupal\Core\Cache\CacheableDependencyTrait;
use Drupal\Core\Cache\CacheableMetadata;
use Drupal\Core\Field\FieldItemList;
use Drupal\Core\TypedData\ComputedItemListTrait;

/**
 * Item list class for computed cacheable string field.
 *
 * This class sets the cacheable metadata on the field item list directly.
 *
 * @see \Drupal\entity_test\Plugin\Field\ComputedTestCacheableStringItemList
 */
class ComputedTestCacheableIntegerItemList extends FieldItemList implements CacheableDependencyInterface {
    use CacheableDependencyTrait, ComputedItemListTrait;
    
    /**
     * {@inheritdoc}
     */
    protected function computeValue() {
        $value = \Drupal::state()->get('entity_test_computed_integer_value', 0);
        $item = $this->createItem(0, $value);
        $cacheability = (new CacheableMetadata())->setCacheContexts([
            'url.query_args:computed_test_cacheable_integer_field',
        ])
            ->setCacheTags([
            'field:computed_test_cacheable_integer_field',
        ])
            ->setCacheMaxAge(31536000);
        $this->setCacheability($cacheability);
        $this->list[0] = $item;
    }

}