I'm building a marketplace application that uses PayPal Express. I've got a form for sellers to input their PayPal API credentials, but I need a way to validate them by making some sort of call to PayPal.
I'm using the PaypalExpressGateway in ActiveMerchant, and I don't see anything other than the standard purchase controls. Is there any sort of null-operation that can be used?
Any help would be greatly appreciated!
I don't have the answer personally. But I know Ryan Bates of Railscasts.com has recently devoted six (!) episodes to ActiveMerchant and Paypal in particular. Check out episodes #141 through #146 at railscasts.com.
For security reasons there isn't a way to check if the email is a valid paypal account. You can always make a small transaction and then void it if account validity is really required.
PayPal does have an AddressVerify API. It confirms whether a postal address and postal code match those of the specified PayPal account holder. I'm in the process of implementing it on our website right now, in fact.
You can read more about it here:
https://www.x.com/docs/DOC-1162#id0862M0QH02L