PayPal APIs: Up and Running, 2nd Edition

Chapter 6. Instant Payment Notifications (IPNs)

Instant Payment Notifications (IPNs) are messages that PayPal sends you regarding a transaction status and can serve a variety of useful purposes. This brief chapter introduces IPNs, covers some of the common use cases for when IPNs can be helpful, and ultimately, teaches you how to use them to perform a follow-up action after a purchase as part of a Tweet Relevance integration.

Note

PayPal’s official documentation on IPNs is available online: Instant Payment Notification Guide.

Overview of IPNs

IPNs notify you when an event occurs that affects a transaction. Typically, these events represent various kinds of payments but could also represent authorizations, Fraud Management Filter actions, refunds, disputes, chargebacks, the status of an eCheck payment, etc. More specifically, IPNs are commonly employed regarding:

• Instant payments, including Express Checkout, Adaptive Payments, and direct credit card payments, and authorizations, which indicate a sale whose payment has not yet been collected

• eCheck payments and associated status, such as pending, completed, or denied, and payments pending for other reasons, such as those being reviewed for potential fraud

• Recurring payment and subscription actions

• Chargebacks, disputes, reversals, and refunds associated with a transaction

Note

See Instant Payments versus eChecks for a brief overview of eChecks versus instant payments.

In many cases, the action that causes the event, such as a payment, occurs ...