ContentLength.php

<?php

declare (strict_types=1);
namespace Drupal\big_pipe\StackMiddleware;

use Drupal\big_pipe\Render\BigPipeResponse;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpKernel\HttpKernelInterface;

/**
 * Defines a big pipe middleware that removes Content-Length headers.
 */
final class ContentLength implements HttpKernelInterface {
  
  /**
   * Constructs a new ContentLength instance.
   *
   * @param \Symfony\Component\HttpKernel\HttpKernelInterface $httpKernel
   *   The wrapped HTTP kernel.
   */
  public function __construct(protected readonly HttpKernelInterface $httpKernel) {
  }
  
  /**
   * {@inheritdoc}
   */
  public function handle(Request $request, $type = self::MAIN_REQUEST, $catch = TRUE) : Response {
    $response = $this->httpKernel
      ->handle($request, $type, $catch);
    if (!$response instanceof BigPipeResponse) {
      return $response;
    }
    $response->headers
      ->remove('Content-Length');
    return $response;
  }

}