Session is not persistent

Hi,

I try to use a session with slim (bryanjhv/slim-session), but after a redirect the session value does not exist. What is wrong here?:

use \Psr\Http\Message\ServerRequestInterface as Request;
use \Psr\Http\Message\ResponseInterface as Response;
use \Interop\Container\ContainerInterface as ContainerInterface;

class AppController extends FilterController
{
protected $ci;
protected $user_session;

//Constructor
public function __construct(ContainerInterface $ci)
{
    $this->ci = $ci;
    $this->user_session = new \SlimSession\Helper;
} 

public function login($request, $response, $args)
{
    $data = $request->getParsedBody();
    $user = ORM::for_table('users')->where('email', $data['email'])->find_one();
    if ($user !== false){
        $this->user_session->set('user_id', $user->id);
        //Printing this works!
        //echo $this->user_session->user_id;
        return $response->withRedirect('/app/list');
    }
}

public function list($request, $response, $args)
{
    //This don't work :-(
    echo $this->user_session->user_id;
}

...

Thank you so much

Hi @fillibuster

Have you already added the middleware according to the documentation?

$app->add(new \Slim\Middleware\Session([
  'name' => 'dummy_session',
  'autorefresh' => true,
  'lifetime' => '1 hour'
]));