dou-smallapp/routes/web.php

<?php

/*
|--------------------------------------------------------------------------
| Web Routes
|--------------------------------------------------------------------------
|
| Here is where you can register web routes for your application. These
| routes are loaded by the RouteServiceProvider within a group which
| contains the "web" middleware group. Now create something great!
|
*/

use Illuminate\Support\Facades\Route;

Route::any('/notify_callback', 'Admin\TemplateController@notify_callback');