test.php

<?php

    use Application\Controller\Shared as SharedController;
    use Psr\Http\Message\RequestInterface;
    
    class Index extends SharedController
    {
    
    public function exampleAction(RequestInterface $request)
    {
        $message = $request->get('message');

        echo $message;
        exit;

        return $this->render('Application:index:example.html.php');
    }
  }  
?>

test.yml

    Example:
        pattern: /example
        defaults: { _controller: "Application:Index:example"}
        requirements:
            _method: POST