如何整合PayPal快速結賬？

Question

我正在開發一個需要PayPal Express結賬功能的wordpress插件。

我在paypal網站上關注如何整合上下文結賬功能的這篇文章（ https://developer.paypal.com/webapps/developer/docs/classic/express-checkout/integration-guide/ECGettingStarted/#id53620a28- e357-4744-9979-66ed5c592183 ）在1步給了我以下表格。

<form method=post action=https://api-3t.sandbox.paypal.com/nvp>
    <input type=hidden name=USER value=API_username>
    <input type=hidden name=PWD value=API_password>
    <input type=hidden name=SIGNATURE value=API_signature>
    <input type=hidden name=VERSION value=XX.0>
    <input type=hidden name=PAYMENTREQUEST_0_PAYMENTACTION value=Sale>
    <input name=PAYMENTREQUEST_0_AMT value=19.95>
    <input type=hidden name=RETURNURL value=https://www.YourReturnURL.com>
    <input type=hidden name=CANCELURL value=https://www.YourCancelURL.com>
    <input type=submit name=METHOD value=SetExpressCheckout>
</form>

我已經從PayPal添加了我自己的API_username，API_password和API_Signature，但是在提交時它顯示ACK=Failure 。

以下是來自PayPal的消息：

TIMESTAMP=2015%2d10%2d30T05%3a27%3a09Z&CORRELATIONID=24cb45b8dd36b&ACK=Failure&VERSION=0%2e000000&BUILD=18308778&L_ERRORCODE0=10002&L_SHORTMESSAGE0=Security%20error&L_LONGMESSAGE0=Security%20header%20is%20not%20valid&L_SEVERITYCODE0=Error

因此，我無法轉到PayPal文檔的第2步，所以需要幫助。 我究竟做錯了什么？

Answer 1

試試我在我的項目中使用的代碼，它的工作原理。

PHP：

$paypal_url='https://www.paypal.com/cgi-bin/webscr'; 
$paypal_id='example@example.com';

HTML：

<form action='<?php echo $paypal_url; ?>' method='post' name='frmPayPal1'>
    <input type='hidden' name='business' value='<?php echo $paypal_id;?>'>
    <input type='hidden' name='cmd' value='_xclick'>
    <input type='hidden' name='item_name' value='Products Total'>
    <input type='hidden' name='amount' value='<?php echo $tot;?>'>
    <input type='hidden' name='no_shipping' value='1'>
    <input type='hidden' name='currency_code' value='USD'>
    <input type='hidden' name='handling' value='0'>
    <input type='hidden' name='cancel_return' value='http://localhost/paypal/cancel.php'>
    <input type='hidden' name='return' value='http://localhost/paypal/success.php'>
    <input type="image" src="https://www.sandbox.paypal.com/en_US/i/btn/btn_buynowCC_LG.gif" border="0" name="submit" alt="PayPal - The safer, easier way to pay online!">
    <img alt="" border="0" src="https://www.sandbox.paypal.com/en_US/i/scr/pixel.gif" width="1" height="1">
</form>

Answer 2

要實現PayPal Express Checkout，您需要執行一些服務器端代碼（PHP，ASP.Net，...）。 你要做的是一個不起作用的HTML表單。 您必須執行3次API調用才能驗證完整付款。

• SetExpressCheckout
• GetExpressCheckoutDetails
• DoExpressCheckoutPayment

在每次通話中，您都將使用您的API憑據。

Answer 3

我建議實施PayPal Express Checkout API。

使用此方法而不是用於創建wordpress插件有很多好處。 主要原因是響應將立即傳遞，您不會使用IPN方法來檢查事務是否成功。 您還可以在一個會話中添加多個定期付款和一次性付款，包括稅收和福利。 你可以自由地添加所有這些東西，幾乎所有東西 - 你的wordpress插件需要很酷！

這只是建議。 這里有一個簡單的（PHP）示例，如何使用多個產品設置事務（也是定期付款）：

// Parameters for SetExpressCheckout, which will be sent to PayPal

$padata['L_BILLINGAGREEMENTDESCRIPTION0']   = 'Product description';
$padata['L_BILLINGAGREEMENTDESCRIPTION0']   = $padata['L_BILLINGAGREEMENTDESCRIPTION0'] . 
' $'.$product->price.'/month';
$padata['L_PAYMENTREQUEST_0_DESC0']     = $padata['L_BILLINGAGREEMENTDESCRIPTION0'] . 
' $'.$product->price.'/month';
$padata['PAYMENTREQUEST_0_NOTIFYURL']         = 'http://site_url/paypal/ipn';
$padata['PAYMENTREQUEST_0_DESC']            = $product->name;
$padata['RETURNURL']                        = 'http://site_url/paypal/returnurl';
$padata['CANCELURL']                        = 'http://site_url/paypal/cancelurl';

$padata['PAYMENTREQUEST_0_CURRENCYCODE']    = 'USD';
$padata['PAYMENTREQUEST_0_PAYMENTACTION']   = 'SALE';
$padata['PAYMENTREQUEST_0_ITEMAMT']     = $product->price;
$padata['PAYMENTREQUEST_0_AMT']          = $product->price;
$padata['L_BILLINGTYPE0']                    = 'RecurringPayments';
$padata['L_PAYMENTREQUEST_0_NAME0']         = $product->name;
$padata['L_PAYMENTREQUEST_0_NUMBER0']      = '322';
$padata['L_PAYMENTREQUEST_0_QTY0']        = '1';
$padata['L_PAYMENTREQUEST_0_AMT0']          = $product->price;
$padata['L_PAYMENTREQUEST_0_NAME1']        = 'Second Product name';
$hosteddata['L_PAYMENTREQUEST_0_DESC1']    = 'second product description';
$hosteddata['L_PAYMENTREQUEST_0_NUMBER1']  = $secondproduct->id;
$hosteddata['L_PAYMENTREQUEST_0_QTY1']      = '1';
$hosteddata['L_PAYMENTREQUEST_0_AMT1']      = $secondproduct->price;

$paypal_data            = http_build_query($padata);
$httpParsedResponseAr   = $this->PPHttpPost('SetExpressCheckout', $paypal_data);

//Respond according to message we receive from Paypal
if("SUCCESS" == strtoupper($httpParsedResponseAr["ACK"]) || "SUCCESSWITHWARNING" == strtoupper($httpParsedResponseAr["ACK"])){

    //Redirect user to PayPal store with Token received.
    $paypalurl ='https://www.paypal.com/cgi-bin/webscr?cmd=_express-checkout&token='.$httpParsedResponseAr["TOKEN"].'';
    header('Location: '.$paypalurl);

}else{
    echo 'Error : '.urldecode($httpParsedResponseAr["L_LONGMESSAGE0"]).'';


}

頁面返回：

$hosteddata['L_BILLINGAGREEMENTDESCRIPTION0']   = 'Recurring Description';
$hosteddata['L_BILLINGAGREEMENTDESCRIPTION0']   = $hosteddata['L_BILLINGAGREEMENTDESCRIPTION0'] . ' $'.$pr->price.'/month';
$hosteddata['L_PAYMENTREQUEST_0_NAME0']         = $pr->name;
$hosteddata['PROFILEREFERENCE']                 = $GetExpressCheckoutDetails['L_PAYMENTREQUEST_0_NUMBER0'];
$hosteddata['PROFILESTARTDATE']               = date('Y-m-d') . 'T' . date('H:i:s').'Z';
$hosteddata['SUBSCRIBERNAME']                    = $GetExpressCheckoutDetails['FIRSTNAME'] . ' ' . $GetExpressCheckoutDetails['LASTNAME'];
$hosteddata['TOKEN']                               = urlencode($_POST['token']);
$hosteddata['DESC']                              = $hosteddata['L_BILLINGAGREEMENTDESCRIPTION0'];
$hosteddata['AMT']                               = $pr->price;
$hosteddata['BILLINGPERIOD']                  = 'Month';
$hosteddata['BILLINGFREQUENCY']                  = '1';
$hosteddata['TOTALBILLINGCYCLES']                = '12';
$hosteddata['REGULARTOTALBILLINGCYCLES']        = '1';
$hosteddata['VERSION']                           = '74.0';
$hosteddata['MAXFAILEDPAYMENTS']              = '1';
$hosteddata['L_PAYMENTREQUEST_0_QTY0']           = '1';
$hosteddata['L_BILLINGTYPE0']                    = 'RecurringPayments';
$hosteddata['L_PAYMENTREQUEST_0_ITEMCATEGORY0']  = 'Digital';
$hosteddata['L_PAYMENTREQUEST_0_AMT0']         = $pr->price;
$hosteddata['INITAMT']                            = $pr->price;
$hosteddata['L_PAYMENTREQUEST_0_NUMBER0']     = $pr->id;
$hosteddata['PAYMENTREQUEST_0_NOTIFYURL']        = 'http://site_url/paypal/ipn';

$padata['L_PAYMENTREQUEST_0_NAME1']      = 'Second Product name';
$hosteddata['L_PAYMENTREQUEST_0_DESC1']         = 'second product description';
$hosteddata['L_PAYMENTREQUEST_0_NUMBER1']       = $secondproduct->id;
$hosteddata['L_PAYMENTREQUEST_0_QTY1']            = '1';
$hosteddata['L_PAYMENTREQUEST_0_AMT1']           = $secondproduct->price;

$paypal_data = http_build_query($hosteddata);
$hosted_saas_response = $this->PPHttpPost('CreateRecurringPaymentsProfile', $paypal_data);

我使用了一個單獨的方法將參數發布到貝寶

private function PPHttpPost( $methodName_, $nvpStr_ ) {

$api_username   = 'yourpaypal@email.com';
$api_password   = 'QWEQWEWQEQWEQEQWE';
$api_signature   = 'WQEQWEQWEQWEWQEQWEQWEQWEQWEQWE.cT';
$api_endpoint    = "https://api-3t.paypal.com/nvp";
$version     = '124.0';

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $api_endpoint);
curl_setopt($ch, CURLOPT_VERBOSE, 1);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);

curl_setopt($ch, CURLOPT_POST, 1);

$nvpreq = "METHOD=$methodName_&VERSION=$version&PWD=$api_password&USER=$api_username&SIGNATURE=$api_signature&$nvpStr_";

curl_setopt($ch, CURLOPT_POSTFIELDS, $nvpreq);
$httpResponse = curl_exec($ch);

if(!$httpResponse) {
    exit("$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.");

}

return $httpParsedResponseAr;

}