Matthew A. Russell - PayPal APIs: Up and Running

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The first edition version of this book, authored by Michael Balderas, essentially presented a consolidation of PayPals online documentation and PHP sample code that focused on using the Name-Value Pairs (NVP) APIs for accessing a variety of the most commonly used PayPal products such as Express Checkout, Website Payments Pro, and Adaptive Payments. This edition builds upon that importantalbeit fairly abstractfoundation with expanded content, including additional coverage on the exciting new Express Checkout for Digital Goods product and Instant Payment Notifications (IPNs), and includes accompanying sample project code that concretely pulls it all together with a realistic web application. As such, a primary goal of this book is to present PayPal products in a fairly standalone, chapter-by-chapter fashion with the key concepts for integrating each product fully implemented as a sample project. Like any other book, this book tells a coherent (and hopefully enjoyable) story from cover to cover. Although you should be able to skip directly to content of interest with minimal difficulty, youll get the greatest benefit if you at least skim the entire book before hopping around too much. Appropriate references will be included to any foundational content from previous chapters as needed.

This book is for any programmer who wants to accept payments for their goods or services through PayPal by using some of PayPals most popular products. You might be a multimillion-dollar corporation, an individual with an open source project looking to accept donations, a nonprofit requesting donations to help a cause, or a software developer writing mobile apps for cell phones. Regardless, PayPal can provide you with solutions, no matter who you are or how much monetary volume youre processing. The code samples in this book are provided as Python web applications that can be deployed on Google App Engine (GAE) with minimal fuss. Python code is inherently highly readable, and reasonable efforts are made to keep it that way versus using any advanced syntax or nonintuitive Python idioms. Furthermore, the code for the sample web applications has been kept as austere and clear of common Python dependenciessuch as Djangoas possible so that it is as universally reusable and portable to other languages as possible.

The official Python tutorial is worth perusing if this is your first encounter with Python; however, you really dont need to actually do any Python programming to benefit from this book. The source code and inline comments should be clear enough that its a fairly trivial exercise for you to port them to your programming platform of choice, and the choice of NVP APIs for PayPal interaction ensures that the payment flows are inherently trivial to understand if you have any programming experience.