Updating an order value with the PayPal PHP SDK - php

Question

OK, I've been banging my head against this for a few days now. I'm building a payment process into a PHP application which will allow for upselling products after a customer approves a payment.
I can get the payment charged to the customer without an issue, but if they select any kind of upsell product which requires the order value to change, then I get errors even though it is following to the letter what was in the documentation I could find...
Below is the test function I'm using, this is the function which is called when the user is redirected back to the website AFTER approving the payment.
public function confirmOrder($payer_id, $payment_id, $incentives = false){
//GET PAYMENT
$payment = Payment::get($payment_id, $this->apiContext);
//CREATE EXECUTION WITH PAYER ID
$execution = new PaymentExecution();
$execution->setPayerId($payer_id);
//APPLY PAYMENT AMOUNT - Original amount was 7.00
$amount = new Amount();
$amount = $amount->setCurrency('GBP')->setTotal('8.00');
//PATCH REPLACE
$patchReplace = new Patch();
$patchReplace = $patchReplace->setOp('replace')->setPath('/transactions/0/amount')->setValue($amount);
//CREATE PATCH OBJECT
$patchRequest = new PatchRequest();
$patchRequest = $patchRequest->setPatches(array($patchReplace));
try {
$payment->update($patchRequest, $this->apiContext);
} catch (PayPalConnectionException $ex) {
return "PATCH ERROR: State(" . $payment->getState() . ") ".$ex->getData();
}
}
This isn't the final code I will use but right now I'm just trying to get an order updated before I build in more of the logic. This code gives me the following error:
PATCH ERROR: State(created) {"name":"PAYMENT_STATE_INVALID","message":"This request is invalid due to the current state of the payment","information_link":"https://developer.paypal.com/webapps/developer/docs/api/#PAYMENT_STATE_INVALID","debug_id":"9caacdc1d652b"}
You can see I'm outputting the getState() which is coming back as 'created' which would normally be fine for updating in everything I can find but it is still failing.
Does anyone else have experience with the PayPal PHP SDK and could help point me in the right direction?

Answer 1

In PayPal, once the user has approved the payment from the consent screen, the amount cannot be changed, as you can understand the user agreed to pay only the amount he/she saw on the consent screen. Modifying the amount after user approves it, is not allowed, and that's why you are seeing that state exception, as the state is already approved.
Anyway, looking at your scenario, I think you might be interested in either creating order, or capture, instead of sale.
Also, in our PayPal-PHP-SDK, there are a lot of interesting documents that could help you understand PHP-SDK better. We also provide a lot of runnable samples, that you could setup in your local machine, by one command only.