ConfigCacheCommand.php

<?php

protected function getFreshConfiguration()
{
    $app = require $this->laravel->bootstrapPath().'/app.php'; // require application kernel of laravel.

    $app->useStoragePath($this->laravel->storagePath()); // storage path.

    $app->make(ConsoleKernelContract::class)->bootstrap(); // bootstraping instanced of ConsoleKernelContract class.

    return $app['config']->all(); // get all of config variables.
}