php__silex__book/src/demo/Middleware/AfterRoute.php

<?php

namespace demo\Middleware;

use Silex\Application;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;

class AfterRoute {
  public static function next(Request $request, Response $response, Application $app) {
    $MESSAGE = "<p>" . $app['timer']->delay() .": in aR</p>\n";
    $content = $response->getContent();
    if ($content !== FALSE) {
      $content .= $MESSAGE;
      $response->setContent($content);
    }
    else {
      // Only echo info on text responses.
      $ct = $response->headers->get('Content-Type');
      if (isset($ct) && strpos($ct, 'text') !== 0) {
        return;
      }
      echo $MESSAGE;
      flush();
    }
  }

}