PayPal AdaptivePayments PaymentDetail PayKey - php

Question

I am using the PayPal Pay API, with Adaptive (Chained) Payments. I am trying to forward a user to paypal and afterwards back to my predefined return_url.
The problem is: I need to have a PayKey within my return-url. Reason for that: I need to call a PaymentDetail API to review the payment within the return_url. And, I don't want to use IPN since I need the validation with some token right on my return Url.
The problem I have is: The PayKey is beeing generated with all the parameters, including the return-url (hence after I build the actual array from which I get my $response from. I can't put the PayKey in the return-Url since it's not generated at this point yet.
//Create request payload with minimum required parameters
$bodyparams = array ("requestEnvelope.errorLanguage" => "en_US",
"actionType" => "PAY",
"currencyCode" => "USD",
"cancelUrl" => "http://www.paypal.com",
"returnUrl" => $return_url . "&payKey=${payKey}", **// Does not work - PAYKEY NEEDED TO ADD???**
"receiverList.receiver(0).email" => "account1#hotmail.com", //TODO
"receiverList.receiver(0).amount" => $price, //TODO
"receiverList.receiver(0).primary" => "true", //TODO
"receiverList.receiver(1).email" => "account2#hotmail.com", //TODO
"receiverList.receiver(1).amount" => $receiver_gets, //TODO
"receiverList.receiver(1).primary" => "false" //TODO
);
// convert payload array into url encoded query string
$body_data = http_build_query($bodyparams, "", chr(38)); // Generates body data
try
{
//create request and add headers
$params = array("http" => array(
"method" => "POST",
"content" => $body_data,
"header" => "X-PAYPAL-SECURITY-USERID: " . $API_UserName . "\r\n" .
"X-PAYPAL-SECURITY-SIGNATURE: " . $API_Signature . "\r\n" .
"X-PAYPAL-SECURITY-PASSWORD: " . $API_Password . "\r\n" .
"X-PAYPAL-APPLICATION-ID: " . $API_AppID . "\r\n" .
"X-PAYPAL-REQUEST-DATA-FORMAT: " . $API_RequestFormat . "\r\n" .
"X-PAYPAL-RESPONSE-DATA-FORMAT: " . $API_ResponseFormat . "\r\n"
));
//create stream context
$ctx = stream_context_create($params);
//open the stream and send request
$fp = #fopen($url, "r", false, $ctx);
//get response
$response = stream_get_contents($fp);
//check to see if stream is open
if ($response === false) {
throw new Exception("php error message = " . "$php_errormsg");
}
fclose($fp);
//parse the ap key from the response
$keyArray = explode("&", $response);
foreach ($keyArray as $rVal){
list($qKey, $qVal) = explode ("=", $rVal);
$kArray[$qKey] = $qVal;
}
//set url to approve the transaction
$payPalURL = "https://www.sandbox.paypal.com/webscr?cmd=_ap-payment&paykey=" . $kArray["payKey"]; **// Here it works fine, since the PayKey is generated at this point ...**
//print the url to screen for testing purposes
If ( $kArray["responseEnvelope.ack"] == "Success") {
echo '<p>' . $payPalURL . '</p>';
}
else {
echo 'ERROR Code: ' . $kArray["error(0).errorId"] . " <br/>";
echo 'ERROR Message: ' . urldecode($kArray["error(0).message"]) . " <br/>";
}
Can somebody help?

Answer 1

I was at this for ages too myself. I finally figured it out. Paypal docs are hard to follow. I found the answer in the paypal adaptive pdf guide which I downloaded. It specifies to add payKey=${payKey} to the end of your return_url. I just tried it there and the paypal get request to my return url now contains the paykey.
So in rails which I'm using the return_url looks like this. Writing a php variable (I think) into the url as instructed by the guide
:return_url => "http://***********.com/paypal-return?payKey=${payKey}"

Answer 2

It seems that you're missing a step in the sequence.
The first step is to send your transaction parameters to
https://svcs.paypal.com/AdaptivePayments/Pay&yourtransactionparameters=blah
[sandbox]https://svcs.sandbox.paypal.com/AdaptivePayments/Pay&yourtransactionparameters=blah
You'll get the paykey in this response.
Once you've retrieved the paykey successfully, you'll call:
https://www.paypal.com/webscr&cmd=_ap-payment&paykey=xxxx
[sandbox]https://www.sandbox.paypal.com/webscr&cmd=_ap-payment&paykey=xxxx
In the second call, the payKey represents the rest of your transaction so you don't have to build another giant query string.

Answer 3

Change your code for:
//Create request payload with minimum required parameters
$bodyparams = array ("requestEnvelope.errorLanguage" => "en_US",
"actionType" => "PAY",
"currencyCode" => "USD",
"cancelUrl" => "http://www.paypal.com",
"returnUrl" => $return_url . '&payKey=${payKey}', **// That's right**
"receiverList.receiver(0).email" => "account1#hotmail.com", //TODO
"receiverList.receiver(0).amount" => $price, //TODO
"receiverList.receiver(0).primary" => "true", //TODO
"receiverList.receiver(1).email" => "account2#hotmail.com", //TODO
"receiverList.receiver(1).amount" => $receiver_gets, //TODO
"receiverList.receiver(1).primary" => "false" //TODO
);
PHP interprets ${payKey} as variable between the double quotes.
Change double quotes (") for simple quotes (')

Answer 4

Apparently you can embed dynamic variables in the return URL: https://www.x.com/thread/49785
Unfortunately, {$payKey} is invalid. so it must be $paykey or $pay_key. Good luck!