SessionMiddleware.php

<?php

namespace App\Middleware;

use Psr\Http\Message\ServerRequestInterface as Request;
use Psr\Http\Message\ResponseInterface as Response;
use Slim\Views\Twig as View;

class SessionMiddleware
{
    protected $view;

    public function __construct(View $view)
    {
        $this->view = $view;
    }

    /**
     * Session Invokable Middleware
     *
     * @param  ServerRequestInterface  $request  PSR7 request object
     * @param  ResponseInterface $response PSR7 response object
     * @param  callable          $next     Next middleware callable
     *
     * @return ResponseInterface PSR7 response object
     */
    public function __invoke(Request $request, Response $response, $next)
    {
        $session = true;
        
        if( !isset($_SESSION['logged-in'])) {
            $session = false;
        }
        
        $this->view[$session];

        $response = $next($request, $response);
        return $response;
    }
}