src/Message/PromotionTransferRequest.php
public function sendData($data)
    {
        $body         = Helper::array2xml($data);
        $client = new Client();
        
        $options = [
            'body'    => $body,
            'verify'  => true,
            'cert'    => $this->getCertPath(),
            'ssl_key' => $this->getKeyPath(),
        ];
        $response = $client->request('POST', $this->endpoint, $options)->getBody();
        $responseData = Helper::xml2array($response);

        return $this->response = new PromotionTransferResponse($this, $responseData);
    }
public function sendData($data)
    {
        $body         = Helper::array2xml($data);
        $client = new Client();
        
        $options = [
            'body'    => $body,
            'verify'  => true,
            'cert'    => $this->getCertPath(),
            'ssl_key' => $this->getKeyPath(),
        ];
        $response = $client->request('POST', $this->endpoint, $options)->getBody();
        $responseData = Helper::xml2array($response);

        return $this->response = new PromotionTransferResponse($this, $responseData);
    }
Send the request with specified data

@param  mixed $data The data to send

@return ResponseInterface