/**
  * Constructor.
  *
  * @param int                           $httpStatusCode   HTTP status code
  * @param mixed                         $errorCode        Internal error code
  * @param string                        $errorTitle       Error description
  * @param Illuminate\Support\MessageBag $errors           Validation errors
  */
 public function __construct($httpStatusCode, $errorCode, $errorTitle, ValidationMessages $errors = NULL)
 {
     $data = ['errors' => []];
     if ($errors) {
         foreach ($errors->keys() as $field) {
             foreach ($errors->get($field) as $message) {
                 $data['errors'][] = ['status' => $httpStatusCode, 'code' => $errorCode, 'title' => 'Validation Fail', 'detail' => $message, 'meta' => ['field' => $field]];
             }
         }
     }
     parent::__construct($data, $httpStatusCode);
 }