This is my first time trying to integrate paypal express checkout into a plugin so bear with me.
My aim is simple, I have a question form, when a user clicks on submit, they are taken to Paypal where they pay a fixed amount (let's say 0.1 USD), on successful payment they are sent back to the question form where their question is submitted. i.e The user has to pay to submit a question.
I went through the paypal integration wizard for Paypal Express, however it is trying to get me to set up a cart, billing, confirm and review page which is total overkill for what I'm trying to do.
Here is the current code I have. Here is my question form:
<?php
$_SESSION['Payment_Amount'] = "0.1";
?>
<div id="askme">
<form id="newask" name="newask" method="post" action="<?php echo plugin_dir_url( __FILE__ ); ?>expresscheckout.php">
<label for="question" id="questionLabel"><?php _e('Your video question link:', 'askme-plugin'); ?></label><br />
<input type="text" id="question" value="" tabindex="1" size="20" name="question" />
<p><input type="submit" class="btn btn-primary" value="Pay and Submit Your Question" tabindex="6" id="submit" name="submit" /></p>
<input type="hidden" name="post_type" id="post_type" value="askme" />
<input type="hidden" name="action" value="post" />
<?php wp_nonce_field( 'new-post' ); ?>
</form>
</div>
Then in expresscheckout.php I have:
<?php
require_once ("paypalfunctions.php");
$paymentAmount = $_SESSION["Payment_Amount"];
$currencyCodeType = "USD";
$paymentType = "Sale";
$returnURL = "http://www.jamespaynedrums.com/ask-a-question/ask-a-question-2?question_confirm=1";
$cancelURL = "http://www.jamespaynedrums.com/ask-a-question/ask-a-question-2?question_cancel=1";
//'------------------------------------
//' Calls the SetExpressCheckout API call
//'
//' The CallShortcutExpressCheckout function is defined in the file PayPalFunctions.php,
//' it is included at the top of this file.
//'-------------------------------------------------
$resArray = CallShortcutExpressCheckout ($paymentAmount, $currencyCodeType, $paymentType, $returnURL, $cancelURL);
$ack = strtoupper($resArray["ACK"]);
if($ack=="SUCCESS" || $ack=="SUCCESSWITHWARNING")
{
RedirectToPayPal ( $resArray["TOKEN"] );
}
else
{
//Display a user friendly Error on the page using any of the following error information returned by PayPal
$ErrorCode = urldecode($resArray["L_ERRORCODE0"]);
$ErrorShortMsg = urldecode($resArray["L_SHORTMESSAGE0"]);
$ErrorLongMsg = urldecode($resArray["L_LONGMESSAGE0"]);
$ErrorSeverityCode = urldecode($resArray["L_SEVERITYCODE0"]);
echo "SetExpressCheckout API call failed. ";
echo "Detailed Error Message: " . $ErrorLongMsg;
echo "Short Error Message: " . $ErrorShortMsg;
echo "Error Code: " . $ErrorCode;
echo "Error Severity Code: " . $ErrorSeverityCode;
}
?>
and finally in paypalfunctions.php (required in expresscheckout.php) I have (with API creds blocked out)
<?php
/********************************************
PayPal API Module
Defines all the global variables and the wrapper functions
********************************************/
$PROXY_HOST = '127.0.0.1';
$PROXY_PORT = '808';
$SandboxFlag = false;
//'------------------------------------
//' PayPal API Credentials
//' Replace <API_USERNAME> with your API Username
//' Replace <API_PASSWORD> with your API Password
//' Replace <API_SIGNATURE> with your Signature
//'------------------------------------
$API_UserName="**BLANKED OUT**";
$API_Password="**BLANKED OUT**";
$API_Signature="**BLANKED OUT**";
// BN Code is only applicable for partners
$sBNCode = "PP-ECWizard";
/*
' Define the PayPal Redirect URLs.
' This is the URL that the buyer is first sent to do authorize payment with their paypal account
' change the URL depending if you are testing on the sandbox or the live PayPal site
'
' For the sandbox, the URL is https://www.sandbox.paypal.com/webscr&cmd=_express-checkout&token=
' For the live site, the URL is https://www.paypal.com/webscr&cmd=_express-checkout&token=
*/
if ($SandboxFlag == true)
{
$API_Endpoint = "https://api-3t.sandbox.paypal.com/nvp";
$PAYPAL_URL = "https://www.sandbox.paypal.com/webscr?cmd=_express-checkout&token=";
}
else
{
$API_Endpoint = "https://api-3t.paypal.com/nvp";
$PAYPAL_URL = "https://www.paypal.com/cgi-bin/webscr?cmd=_express-checkout&token=";
}
$USE_PROXY = false;
$version="93";
if (session_id() == "")
session_start();
/* An express checkout transaction starts with a token, that
identifies to PayPal your transaction
In this example, when the script sees a token, the script
knows that the buyer has already authorized payment through
paypal. If no token was found, the action is to send the buyer
to PayPal to first authorize payment
*/
/*
'-------------------------------------------------------------------------------------------------------------------------------------------
' Purpose: Prepares the parameters for the SetExpressCheckout API Call.
' Inputs:
' paymentAmount: Total value of the shopping cart
' currencyCodeType: Currency code value the PayPal API
' paymentType: paymentType has to be one of the following values: Sale or Order or Authorization
' returnURL: the page where buyers return to after they are done with the payment review on PayPal
' cancelURL: the page where buyers return to when they cancel the payment review on PayPal
'--------------------------------------------------------------------------------------------------------------------------------------------
*/
function CallShortcutExpressCheckout( $paymentAmount, $currencyCodeType, $paymentType, $returnURL, $cancelURL)
{
//------------------------------------------------------------------------------------------------------------------------------------
// Construct the parameter string that describes the SetExpressCheckout API call in the shortcut implementation
$nvpstr="&PAYMENTREQUEST_0_AMT=". $paymentAmount;
$nvpstr = $nvpstr . "&PAYMENTREQUEST_0_PAYMENTACTION=" . $paymentType;
$nvpstr = $nvpstr . "&RETURNURL=" . $returnURL;
$nvpstr = $nvpstr . "&CANCELURL=" . $cancelURL;
$nvpstr = $nvpstr . "&PAYMENTREQUEST_0_CURRENCYCODE=" . $currencyCodeType;
$_SESSION["currencyCodeType"] = $currencyCodeType;
$_SESSION["PaymentType"] = $paymentType;
//'---------------------------------------------------------------------------------------------------------------
//' Make the API call to PayPal
//' If the API call succeded, then redirect the buyer to PayPal to begin to authorize payment.
//' If an error occured, show the resulting errors
//'---------------------------------------------------------------------------------------------------------------
$resArray=hash_call("SetExpressCheckout", $nvpstr);
$ack = strtoupper($resArray["ACK"]);
if($ack=="SUCCESS" || $ack=="SUCCESSWITHWARNING")
{
$token = urldecode($resArray["TOKEN"]);
$_SESSION['TOKEN']=$token;
}
return $resArray;
}
/*
'-------------------------------------------------------------------------------------------------------------------------------------------
' Purpose: Prepares the parameters for the SetExpressCheckout API Call.
' Inputs:
' paymentAmount: Total value of the shopping cart
' currencyCodeType: Currency code value the PayPal API
' paymentType: paymentType has to be one of the following values: Sale or Order or Authorization
' returnURL: the page where buyers return to after they are done with the payment review on PayPal
' cancelURL: the page where buyers return to when they cancel the payment review on PayPal
' shipToName: the Ship to name entered on the merchant's site
' shipToStreet: the Ship to Street entered on the merchant's site
' shipToCity: the Ship to City entered on the merchant's site
' shipToState: the Ship to State entered on the merchant's site
' shipToCountryCode: the Code for Ship to Country entered on the merchant's site
' shipToZip: the Ship to ZipCode entered on the merchant's site
' shipToStreet2: the Ship to Street2 entered on the merchant's site
' phoneNum: the phoneNum entered on the merchant's site
'--------------------------------------------------------------------------------------------------------------------------------------------
*/
function CallMarkExpressCheckout( $paymentAmount, $currencyCodeType, $paymentType, $returnURL,
$cancelURL, $shipToName, $shipToStreet, $shipToCity, $shipToState,
$shipToCountryCode, $shipToZip, $shipToStreet2, $phoneNum
)
{
//------------------------------------------------------------------------------------------------------------------------------------
// Construct the parameter string that describes the SetExpressCheckout API call in the shortcut implementation
$nvpstr="&PAYMENTREQUEST_0_AMT=". $paymentAmount;
$nvpstr = $nvpstr . "&PAYMENTREQUEST_0_PAYMENTACTION=" . $paymentType;
$nvpstr = $nvpstr . "&RETURNURL=" . $returnURL;
$nvpstr = $nvpstr . "&CANCELURL=" . $cancelURL;
$nvpstr = $nvpstr . "&PAYMENTREQUEST_0_CURRENCYCODE=" . $currencyCodeType;
$nvpstr = $nvpstr . "&ADDROVERRIDE=1";
$nvpstr = $nvpstr . "&PAYMENTREQUEST_0_SHIPTONAME=" . $shipToName;
$nvpstr = $nvpstr . "&PAYMENTREQUEST_0_SHIPTOSTREET=" . $shipToStreet;
$nvpstr = $nvpstr . "&PAYMENTREQUEST_0_SHIPTOSTREET2=" . $shipToStreet2;
$nvpstr = $nvpstr . "&PAYMENTREQUEST_0_SHIPTOCITY=" . $shipToCity;
$nvpstr = $nvpstr . "&PAYMENTREQUEST_0_SHIPTOSTATE=" . $shipToState;
$nvpstr = $nvpstr . "&PAYMENTREQUEST_0_SHIPTOCOUNTRYCODE=" . $shipToCountryCode;
$nvpstr = $nvpstr . "&PAYMENTREQUEST_0_SHIPTOZIP=" . $shipToZip;
$nvpstr = $nvpstr . "&PAYMENTREQUEST_0_SHIPTOPHONENUM=" . $phoneNum;
$_SESSION["currencyCodeType"] = $currencyCodeType;
$_SESSION["PaymentType"] = $paymentType;
//'---------------------------------------------------------------------------------------------------------------
//' Make the API call to PayPal
//' If the API call succeded, then redirect the buyer to PayPal to begin to authorize payment.
//' If an error occured, show the resulting errors
//'---------------------------------------------------------------------------------------------------------------
$resArray=hash_call("SetExpressCheckout", $nvpstr);
$ack = strtoupper($resArray["ACK"]);
if($ack=="SUCCESS" || $ack=="SUCCESSWITHWARNING")
{
$token = urldecode($resArray["TOKEN"]);
$_SESSION['TOKEN']=$token;
}
return $resArray;
}
/*
'-------------------------------------------------------------------------------------------
' Purpose: Prepares the parameters for the GetExpressCheckoutDetails API Call.
'
' Inputs:
' None
' Returns:
' The NVP Collection object of the GetExpressCheckoutDetails Call Response.
'-------------------------------------------------------------------------------------------
*/
function GetShippingDetails( $token )
{
//'--------------------------------------------------------------
//' At this point, the buyer has completed authorizing the payment
//' at PayPal. The function will call PayPal to obtain the details
//' of the authorization, incuding any shipping information of the
//' buyer. Remember, the authorization is not a completed transaction
//' at this state - the buyer still needs an additional step to finalize
//' the transaction
//'--------------------------------------------------------------
//'---------------------------------------------------------------------------
//' Build a second API request to PayPal, using the token as the
//' ID to get the details on the payment authorization
//'---------------------------------------------------------------------------
$nvpstr="&TOKEN=" . $token;
//'---------------------------------------------------------------------------
//' Make the API call and store the results in an array.
//' If the call was a success, show the authorization details, and provide
//' an action to complete the payment.
//' If failed, show the error
//'---------------------------------------------------------------------------
$resArray=hash_call("GetExpressCheckoutDetails",$nvpstr);
$ack = strtoupper($resArray["ACK"]);
if($ack == "SUCCESS" || $ack=="SUCCESSWITHWARNING")
{
$_SESSION['payer_id'] = $resArray['PAYERID'];
}
return $resArray;
}
/*
'-------------------------------------------------------------------------------------------------------------------------------------------
' Purpose: Prepares the parameters for the GetExpressCheckoutDetails API Call.
'
' Inputs:
' sBNCode: The BN code used by PayPal to track the transactions from a given shopping cart.
' Returns:
' The NVP Collection object of the GetExpressCheckoutDetails Call Response.
'--------------------------------------------------------------------------------------------------------------------------------------------
*/
function ConfirmPayment( $FinalPaymentAmt )
{
/* Gather the information to make the final call to
finalize the PayPal payment. The variable nvpstr
holds the name value pairs
*/
//Format the other parameters that were stored in the session from the previous calls
$token = urlencode($_SESSION['TOKEN']);
$paymentType = urlencode($_SESSION['PaymentType']);
$currencyCodeType = urlencode($_SESSION['currencyCodeType']);
$payerID = urlencode($_SESSION['payer_id']);
$serverName = urlencode($_SERVER['SERVER_NAME']);
$nvpstr = '&TOKEN=' . $token . '&PAYERID=' . $payerID . '&PAYMENTREQUEST_0_PAYMENTACTION=' . $paymentType . '&PAYMENTREQUEST_0_AMT=' . $FinalPaymentAmt;
$nvpstr .= '&PAYMENTREQUEST_0_CURRENCYCODE=' . $currencyCodeType . '&IPADDRESS=' . $serverName;
/* Make the call to PayPal to finalize payment
If an error occured, show the resulting errors
*/
$resArray=hash_call("DoExpressCheckoutPayment",$nvpstr);
/* Display the API response back to the browser.
If the response from PayPal was a success, display the response parameters'
If the response was an error, display the errors received using APIError.php.
*/
$ack = strtoupper($resArray["ACK"]);
return $resArray;
}
/*
'-------------------------------------------------------------------------------------------------------------------------------------------
' Purpose: This function makes a DoDirectPayment API call
'
' Inputs:
' paymentType: paymentType has to be one of the following values: Sale or Order or Authorization
' paymentAmount: total value of the shopping cart
' currencyCode: currency code value the PayPal API
' firstName: first name as it appears on credit card
' lastName: last name as it appears on credit card
' street: buyer's street address line as it appears on credit card
' city: buyer's city
' state: buyer's state
' countryCode: buyer's country code
' zip: buyer's zip
' creditCardType: buyer's credit card type (i.e. Visa, MasterCard ... )
' creditCardNumber: buyers credit card number without any spaces, dashes or any other characters
' expDate: credit card expiration date
' cvv2: Card Verification Value
'
'-------------------------------------------------------------------------------------------
'
' Returns:
' The NVP Collection object of the DoDirectPayment Call Response.
'--------------------------------------------------------------------------------------------------------------------------------------------
*/
function DirectPayment( $paymentType, $paymentAmount, $creditCardType, $creditCardNumber,
$expDate, $cvv2, $firstName, $lastName, $street, $city, $state, $zip,
$countryCode, $currencyCode )
{
//Construct the parameter string that describes DoDirectPayment
$nvpstr = "&AMT=" . $paymentAmount;
$nvpstr = $nvpstr . "&CURRENCYCODE=" . $currencyCode;
$nvpstr = $nvpstr . "&PAYMENTACTION=" . $paymentType;
$nvpstr = $nvpstr . "&CREDITCARDTYPE=" . $creditCardType;
$nvpstr = $nvpstr . "&ACCT=" . $creditCardNumber;
$nvpstr = $nvpstr . "&EXPDATE=" . $expDate;
$nvpstr = $nvpstr . "&CVV2=" . $cvv2;
$nvpstr = $nvpstr . "&FIRSTNAME=" . $firstName;
$nvpstr = $nvpstr . "&LASTNAME=" . $lastName;
$nvpstr = $nvpstr . "&STREET=" . $street;
$nvpstr = $nvpstr . "&CITY=" . $city;
$nvpstr = $nvpstr . "&STATE=" . $state;
$nvpstr = $nvpstr . "&COUNTRYCODE=" . $countryCode;
$nvpstr = $nvpstr . "&IPADDRESS=" . $_SERVER['REMOTE_ADDR'];
$resArray=hash_call("DoDirectPayment", $nvpstr);
return $resArray;
}
/**
'-------------------------------------------------------------------------------------------------------------------------------------------
* hash_call: Function to perform the API call to PayPal using API signature
* @methodName is name of API method.
* @nvpStr is nvp string.
* returns an associtive array containing the response from the server.
'-------------------------------------------------------------------------------------------------------------------------------------------
*/
function hash_call($methodName,$nvpStr)
{
//declaring of global variables
global $API_Endpoint, $version, $API_UserName, $API_Password, $API_Signature;
global $USE_PROXY, $PROXY_HOST, $PROXY_PORT;
global $gv_ApiErrorURL;
global $sBNCode;
//setting the curl parameters.
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL,$API_Endpoint);
curl_setopt($ch, CURLOPT_VERBOSE, 1);
//turning off the server and peer verification(TrustManager Concept).
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);
curl_setopt($ch, CURLOPT_RETURNTRANSFER,1);
curl_setopt($ch, CURLOPT_POST, 1);
//if USE_PROXY constant set to TRUE in Constants.php, then only proxy will be enabled.
//Set proxy name to PROXY_HOST and port number to PROXY_PORT in constants.php
if($USE_PROXY)
curl_setopt ($ch, CURLOPT_PROXY, $PROXY_HOST. ":" . $PROXY_PORT);
//NVPRequest for submitting to server
$nvpreq="METHOD=" . urlencode($methodName) . "&VERSION=" . urlencode($version) . "&PWD=" . urlencode($API_Password) . "&USER=" . urlencode($API_UserName) . "&SIGNATURE=" . urlencode($API_Signature) . $nvpStr . "&BUTTONSOURCE=" . urlencode($sBNCode);
//setting the nvpreq as POST FIELD to curl
curl_setopt($ch, CURLOPT_POSTFIELDS, $nvpreq);
//getting response from server
$response = curl_exec($ch);
//convrting NVPResponse to an Associative Array
$nvpResArray=deformatNVP($response);
$nvpReqArray=deformatNVP($nvpreq);
$_SESSION['nvpReqArray']=$nvpReqArray;
if (curl_errno($ch))
{
// moving to display page to display curl errors
$_SESSION['curl_error_no']=curl_errno($ch) ;
$_SESSION['curl_error_msg']=curl_error($ch);
//Execute the Error handling module to display errors.
}
else
{
//closing the curl
curl_close($ch);
}
return $nvpResArray;
}
/*'----------------------------------------------------------------------------------
Purpose: Redirects to PayPal.com site.
Inputs: NVP string.
Returns:
----------------------------------------------------------------------------------
*/
function RedirectToPayPal ( $token )
{
global $PAYPAL_URL;
// Redirect to paypal.com here
$payPalURL = $PAYPAL_URL . $token;
header("Location: ".$payPalURL);
exit;
}
/*'----------------------------------------------------------------------------------
* This function will take NVPString and convert it to an Associative Array and it will decode the response.
* It is usefull to search for a particular key and displaying arrays.
* @nvpstr is NVPString.
* @nvpArray is Associative Array.
----------------------------------------------------------------------------------
*/
function deformatNVP($nvpstr)
{
$intial=0;
$nvpArray = array();
while(strlen($nvpstr))
{
//postion of Key
$keypos= strpos($nvpstr,'=');
//position of value
$valuepos = strpos($nvpstr,'&') ? strpos($nvpstr,'&'): strlen($nvpstr);
/*getting the Key and Value values and storing in a Associative Array*/
$keyval=substr($nvpstr,$intial,$keypos);
$valval=substr($nvpstr,$keypos+1,$valuepos-$keypos-1);
//decoding the respose
$nvpArray[urldecode($keyval)] =urldecode( $valval);
$nvpstr=substr($nvpstr,$valuepos+1,strlen($nvpstr));
}
return $nvpArray;
}
?>
Currently, when I click on my form submit button, I am taken to paypal, I log in and it is trying to charge me 1GBP - not 0.1USD.
Also worth mentioning that this is a wordpress plugin, and at the top of my file containing the form (askme.php) I have the following code:
add_action('init', 'myStartSession', 1);
add_action('wp_logout', 'myEndSession');
add_action('wp_login', 'myEndSession');
function myStartSession() {
if(!session_id()) {
session_start();
}
}
function myEndSession() {
session_destroy ();
}
