Sailthru_Client::prepareJsonPayload PHP Method

    protected function prepareJsonPayload(array $data, array $binary_data = [])
    {
        $payload = ['api_key' => $this->api_key, 'format' => 'json', 'json' => json_encode($data)];
        $payload['sig'] = Sailthru_Util::getSignatureHash($payload, $this->secret);
        if (!empty($binary_data)) {
            $payload = array_merge($payload, $binary_data);
        }
        return $payload;
    }