Paypal: Get Buyer ID before IPN received (Express checkout, PHP)

Question

Payal say that IPN can take a while for orders to be relayed. I am wondering if there is a way with the other Paypal APIs to instantly fetch information about an order, the moment the user is redirected to the success URL of my site.

The problem is that only two variables seem to be relayed in the querystring to my success page: token and PayerID.

The reason I want to do this is I want to allow users to complete the checkout process without logging into my site, but then once the order is complete and they're sent to my success page, I want my site to be able to link them to their previous orders as well as this one, which would be extracted from my database.

Can this be done using token and/or PayerID? If so, how? (I'm using the PHP scripts that the Express checkout wizard provides)

Answer 1

IPN is generally pretty much real-time. There are times when it gets a little lagged and can be kind of slow, but it doesn't seem to happen all that much.

That said, the API calls along within your checkout will indeed return lots of good info in the actual response. Your URL only has the parameters you mentioned (token and Payer ID), however, the GetExpressCheckoutDetails response would have all the buyer info you need, and DoExpressCheckoutPayment will return the transaction ID, payment status, payer status, etc. So the DECP probably has the majority of what you're after.

You can use session variables to save GECD response data and DECP response data accordingly and then update your database, send out email notifications, etc. after calling DECP.

The thing is, the payment could end up being "pending" for various reasons. As such, IPN would still be the best way to handle this sort of thing so that you can update your DB and send out one notification for the pending payment being received, and then another update/email once that payment actually clears.