PsrResponseSubscriber.php

<?php

namespace Drupal\Core\EventSubscriber;

use Psr\Http\Message\ResponseInterface;
use Symfony\Bridge\PsrHttpMessage\HttpFoundationFactoryInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\HttpKernel\Event\ViewEvent;
use Symfony\Component\HttpKernel\KernelEvents;

/**
 * Response subscriber for handling PSR-7 responses.
 */
class PsrResponseSubscriber implements EventSubscriberInterface {
    
    /**
     * The httpFoundation factory.
     *
     * @var \Symfony\Bridge\PsrHttpMessage\HttpFoundationFactoryInterface
     */
    protected $httpFoundationFactory;
    
    /**
     * Constructs a new PathRootsSubscriber instance.
     *
     * @param \Symfony\Bridge\PsrHttpMessage\HttpFoundationFactoryInterface $http_foundation_factory
     *   The httpFoundation factory.
     */
    public function __construct(HttpFoundationFactoryInterface $http_foundation_factory) {
        $this->httpFoundationFactory = $http_foundation_factory;
    }
    
    /**
     * Converts a PSR-7 response to a Symfony response.
     *
     * @param \Symfony\Component\HttpKernel\Event\ViewEvent $event
     *   The Event to process.
     */
    public function onKernelView(ViewEvent $event) {
        $controller_result = $event->getControllerResult();
        if ($controller_result instanceof ResponseInterface) {
            $event->setResponse($this->httpFoundationFactory
                ->createResponse($controller_result));
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public static function getSubscribedEvents() : array {
        $events[KernelEvents::VIEW][] = [
            'onKernelView',
        ];
        return $events;
    }

}