PayPal

MediaWiki Extension

MW:Extension:PayPal is an extension for creating PayPal donation forms using a <paypal> tag. PokerCoder requested adding IPN support to the extension through this RentACoder job and has accepted User:Nad's bid to complete the work.

IPN

Instant Payment Notification, included with Website Payment products, Express Checkout, and Standard Checkout, is available to PayPal Premier and Business members. Instant Payment Notification allows you to integrate your PayPal payments with your website's back-end operations, so that you get immediate notification and authentication of any PayPal payments and disputes you may receive.

When a customer makes a payment to you, PayPal will post a notification to your server at a URL you specify. Included in this notification will be all of your customer's payment information (e.g. customer name, amount) as well as a piece of encrypted code. When your server receives a notification, it will then post the information, including the encrypted code, back to a secure PayPal URL. PayPal will authenticate the transaction by checking the encrypted string. This post-back of the IPN data to PayPal prevents "spoofing," so you can be sure that the IPN came from PayPal. Upon verification, PayPal will send confirmation of its validity back to your server.

• IPN at PayPal Integration Center
• IPN Introduction for Developers
• DesignerTuts Tutorial
• IPN Manual
• IPN Technical Overview
• Instant Code Samples
• IPN Techniques
• Basic Inventory Management Using IPN
• IPN Test Environment
• IPN PHP Script Generator
• Good IPN tech info

PDT

• What's the difference between IPN and PDT?

PayPal Sandbox

The paypal sandbox allows all operations done within the paypal site to be performed within a test environment. To test paypal code working in other sites and applications. It's useful to have a wildcard email domain so you can use any number of email addresses for different accounts etc. First, sign up as a developer at https://developer.paypal.com with one "master" email address.

Next set up a test account at https://www.sandbox.paypal.com (the session will be logged in as the master account, and the test account gets created under that). You need to confirm the email address to make the test account verified, but note that the confirmation email must be checked from within the paypal developer site, it is not sent directly to the email address. Next add and confirm a bank account and a credit card for the test account (the site will supply the account numbers for these).