public function config($params)
 {
     Veritrans::$serverKey = $params['server_key'];
     Veritrans::$isProduction = $params['production'];
 }
 public function __construct()
 {
     Veritrans::$serverKey = '<your server key>';
     Veritrans::$isProduction = false;
 }
 public function __construct()
 {
     Veritrans::$serverKey = '<your server key>';
     //set Veritrans::$isProduction  value to true for production mode
     Veritrans::$isProduction = false;
 }