private function _postProcess() { if (Tools::isSubmit('submit')) { $this->_postProcessCredential(); include_once _PS_MODULE_DIR_ . 'gointerpay/Rest.php'; $rest = new Rest(Configuration::get('GOINTERPAY_STORE'), Configuration::get('GOINTERPAY_SECRET')); if (!$rest->checkCredentials('store=' . Configuration::get('GOINTERPAY_STORE') . '&secret=' . Configuration::get('GOINTERPAY_SECRET') . '&test=true')) { $this->_postErrors[] = $this->l('Invalid credentials, please double-check you store ID and secret. If this issue persists, please contact GoInterpay.'); } } else { $this->_postProcessShipping(); } }