CacheableDocumentationProcessor.php

<?php

/*
 * This file is part of the API Platform project.
 *
 * (c) Kévin Dunglas <dunglas@gmail.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

declare(strict_types=1);

namespace ApiPlatform\State\Processor;

use ApiPlatform\Metadata\Operation;
use ApiPlatform\State\ProcessorInterface;
use ApiPlatform\State\StopwatchAwareInterface;
use ApiPlatform\State\StopwatchAwareTrait;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;

/**
 * Adds an ETag and revalidating Cache-Control headers on the API documentation
 * and entrypoint responses so clients can avoid re-downloading the (often large)
 * payload when nothing changed.
 *
 * @template T1
 * @template T2
 *
 * @implements ProcessorInterface<T1, T2>
 */
final class CacheableDocumentationProcessor implements ProcessorInterface, StopwatchAwareInterface
{
    use StopwatchAwareTrait;

    /**
     * @param ProcessorInterface<T1, T2> $decorated
     */
    public function __construct(
        private readonly ProcessorInterface $decorated,
        private readonly int $maxAge = 0,
        private readonly ?int $sharedMaxAge = null,
        private readonly bool $public = true,
        private readonly bool $mustRevalidate = true,
        private readonly bool $etag = true,
    ) {
    }

    public function process(mixed $data, Operation $operation, array $uriVariables = [], array $context = []): mixed
    {
        $response = $this->decorated->process($data, $operation, $uriVariables, $context);

        if (!$response instanceof Response || 200 !== $response->getStatusCode()) {
            return $response;
        }

        $content = $response->getContent();
        if (false === $content || '' === $content) {
            return $response;
        }

        $this->stopwatch?->start('api_platform.processor.cacheable_documentation');

        if ($this->etag) {
            $response->setEtag(md5($content));
        }

        if ($this->public) {
            $response->setPublic();
        } else {
            $response->setPrivate();
        }

        $response->setMaxAge($this->maxAge);

        if (null !== $this->sharedMaxAge) {
            $response->setSharedMaxAge($this->sharedMaxAge);
        }

        if ($this->mustRevalidate) {
            $response->headers->addCacheControlDirective('must-revalidate');
        }

        if ($this->etag && ($request = $context['request'] ?? null) instanceof Request) {
            $response->isNotModified($request);
        }

        $this->stopwatch?->stop('api_platform.processor.cacheable_documentation');

        return $response;
    }
}