misc_pterodactyl-panel/app/Http/Middleware/AdminAuthenticate.php

<?php
/**
 * Pterodactyl - Panel
 * Copyright (c) 2015 - 2017 Dane Everitt <dane@daneeveritt.com>.
 *
 * This software is licensed under the terms of the MIT license.
 * https://opensource.org/licenses/MIT
 */

namespace Pterodactyl\Http\Middleware;

use Closure;
use Illuminate\Http\Request;
use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;

class AdminAuthenticate
{
    /**
     * Handle an incoming request.
     *
     * @return mixed
     *
     * @throws \Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException
     */
    public function handle(Request $request, Closure $next)
    {
        if (!$request->user() || !$request->user()->root_admin) {
            throw new AccessDeniedHttpException();
        }

        return $next($request);
    }
}