public function getElasticConfig($key = 'config', $prefix = 'elasticquent')
    {
        $key = $prefix . ($key ? '.' : '') . $key;

        if (function_exists('config')) {
            // Get config helper for Laravel 5.1+
            $config_helper = config();
        } elseif (function_exists('app')) {
            // Get config helper for Laravel 4 & Laravel 5.1
            $config_helper = app('config');
        } else {
            // Create a config helper when using stand-alone Eloquent
            $config_helper = $this->getConfigHelper();
        }

        return $config_helper->get($key);
    }