php - PHP での Paypal Masspay API

Question

PHP Webページにpaypal masspay APIを実装しています。

しかし、現在、以下に説明する1つのエラーで立ち往生しています：

MassPay の失敗: SSL 接続エラー (35) https://api-3t.sandbox.paypal.com/nvpへの POST 要求 (METHOD=MassPay&VERSION=93&PWD=TNQAETBEXP7ZC9P9&USER=_______) に対する無効な HTTP 応答。

これが私のコードです：

 $vEmailSubject = 'Mass Payment';

        /** MassPay NVP example.
         *
         *  Pay one or more recipients. 
        */

        // For testing environment: use 'sandbox' option. Otherwise, use 'live'.
        // Go to www.x.com (PayPal Integration center) for more information.
        $environment = 'sandbox'; // or 'beta-sandbox' or 'live'.

        /**
         * Send HTTP POST Request
         *
         * @param string The API method name
         * @param string The POST Message fields in &name=value pair format
         * @return array Parsed HTTP Response body
         */

        function PPHttpPost($methodName_, $nvpStr_)
        {
            global $environment;

            // Set up your API credentials, PayPal end point, and API version.
            // How to obtain API credentials:
            // https://cms.paypal.com/us/cgi-bin/?cmd=_render-content&content_ID=developer/e_howto_api_NVPAPIBasics#id084E30I30RO
            $API_UserName = urlencode('UserName');
            $API_Password = urlencode('Password');
            $API_Signature = urlencode('Signature');
            $API_Endpoint = "https://api-3t.sandbox.paypal.com/nvp";

            if("sandbox" === $environment || "beta-sandbox" === $environment)
            {
                $API_Endpoint = "https://api-3t.sandbox.paypal.com/nvp";
            }


            $version = urlencode('93');

            // Set the curl parameters.
            $ch = curl_init();
            curl_setopt($ch, CURLOPT_URL, $API_Endpoint);
            curl_setopt($ch, CURLOPT_VERBOSE, 1);

            // Turn off the server and peer verification (TrustManager Concept).
            curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
            curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);
            curl_setopt($ch, CURLOPT_SSLVERSION , 1);
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
            curl_setopt($ch, CURLOPT_POST, 1);


            // Set the API operation, version, and API signature in the request.

            $nvpreq = "METHOD=MassPay&VERSION=$version&PWD=$API_Password&USER=$API_UserName&SIGNATURE=$API_Signature$nvpStr_";

            // Set the request as a POST FIELD for curl.
            curl_setopt($ch, CURLOPT_POSTFIELDS, $nvpreq."&".$nvpStr_);

            // Get response from the server.
            $httpResponse = curl_exec($ch);

            if( !$httpResponse)
            {
             echo $methodName_ . ' failed: ' . curl_error($ch) . '(' . curl_errno($ch) .')';
            }

            // Extract the response details.
            $httpResponseAr = explode("&", $httpResponse);

            $httpParsedResponseAr = array();
            foreach ($httpResponseAr as $i => $value)
            {
             $tmpAr = explode("=", $value);
             if(sizeof($tmpAr) > 1)
             {
              $httpParsedResponseAr[$tmpAr[0]] = $tmpAr[1];
             }
            }

            if((0 == sizeof($httpParsedResponseAr)) || !array_key_exists('ACK', $httpParsedResponseAr))
            {
             exit("Invalid HTTP Response for POST request($nvpreq) to $API_Endpoint.");
            }
            print_r($httpParsedResponseAr);

            return $httpParsedResponseAr;
        }

        // Set request-specific fields.
        $emailSubject = urlencode($vEmailSubject);
        $receiverType = urlencode('EmailAddress');
        $currency = urlencode('USD'); // or other currency ('GBP', 'EUR', 'JPY', 'CAD', 'AUD')

        // Receivers
        // Use '0' for a single receiver. In order to add new ones: (0, 1, 2, 3...)
        // Here you can modify to obtain array data from database.

        $receivers = array(
            0 => array(
            'receiverEmail' => 'Receiver mail id', 
            'amount' => 100,
            'uniqueID' => 10, // 13 chars max
            'note' => "Transfer amount to Person"),
            1 => array(
            'receiverEmail' => 'Receiver mail id 2', 
            'amount' => 200,
            'uniqueID' => 11, // 13 chars max
            'note' => "Transfer amount to Person")
        );

        $receiversLenght = count($receivers);

        // Add request-specific fields to the request string.
        $nvpStr="&EMAILSUBJECT=$emailSubject&RECEIVERTYPE=$receiverType&CURRENCYCODE=$currency";

        $receiversArray = array();

        for($i = 0; $i < $receiversLenght; $i++)
        {
         $receiversArray[$i] = $receivers[$i];
        }

        foreach($receiversArray as $i => $receiverData)
        {
         $receiverEmail = urlencode($receiverData['receiverEmail']);
         $amount = urlencode($receiverData['amount']);
         $uniqueID = urlencode($receiverData['uniqueID']);
         $note = urlencode($receiverData['note']);
         $nvpStr .= "&L_EMAIL$i=$receiverEmail&L_Amt$i=$amount&L_UNIQUEID$i=$uniqueID&L_NOTE$i=$note";
        }

        // Execute the API operation; see the PPHttpPost function above.
        $httpParsedResponseAr = PPHttpPost('MassPay', $nvpStr);

        if("SUCCESS" == strtoupper($httpParsedResponseAr["ACK"]) || "SUCCESSWITHWARNING" == strtoupper($httpParsedResponseAr["ACK"]))
        {
            echo 'MassPay Completed Successfully: ' . $httpParsedResponseAr;
        }
        else
        {
            echo '\nMassPay failed: ';
            print_r($httpParsedResponseAr);
        }