protected function parseValues(array $parameters)
    {
        $signable = [];

        foreach ($parameters as $key => &$parameter) {

            // JSON an array value
            $parameter = $this->arrayToJson($parameter);

            // Append a secret to the present webhooks
            $parameter = $this->appendSecretToWebhook($key, $parameter);

            // Put the value string to the signable data
            $signable[] = $key . '=' . (string)$parameter;
        }

        $signable = implode('&', $signable);

        return compact('parameters', 'signable');
    }