Pro Paypal E-Commerce

Damon Williams

Introduction to PayPal

The PayPal Account

 Basic Website Payments

Encrypted Website Payments

Postpayment Processing

The PayPal API

Payflow Gateway

Reporting

Managing Online Disputes

PayPal Reference

Purchase Now !
Just with Paypal

Book Details

Price	3.00 USD
Pages	306 p
File Size	4,291 KB
File Type	PDF format
ISBN-13 (pbk)   ISBN-10 (pbk)	978-1-59059-750-7  1-59059-750-8
Copyright	2007 by Damon Williams

About the Author

DAMON WILLIAMS has worked at PayPal since 2004, where he has

specialized in making life easier for people trying to integrate PayPal

into websites and applications. His background includes experience

in software engineering, information architecture, community

building, and publishing. Before working at PayPal, Damon spent

five years as the publisher of Feedback Magazine in Austin, Texas,

where he also moonlighted as a DJ and promoter. He currently manages

PayPal’s developer program, where he is building a global community for innovation

and support on the PayPal platform. Damon holds a bachelor’s degree in electrical engineering

from the University of Texas at Austin.

About the Technical Reviewer

MICHAEL BLANTON is the Senior Manager of Merchant Integration for PayPal Merchant

Services and has been with the Merchant Services team for three years. During that time,

he’s provided technical consulting to partners such as Dell, Apple iTunes, Napster, and

Chase Paymentech. He has also presented PayPal integration information at conferences

and contributed to numerous open source projects based on Java technology. He has

over eight years of experience in e-commerce consulting and over ten years of experience

with online payments processing.

Acknowledgments

Iwould like to thank all of the people I have worked with during my first two years at

PayPal. I wish I could list all the names, but the list would be too long and I would still

probably leave some people out. Working at PayPal has been a tremendous learning

experience, both personally and professionally.

Thank you to the following people for contributing to this book in the form of code,

advice, images, support, or guidance: Yannick Bercy, Michael Blanton, Patrick Breitenbach,

Dave Burchell, Paulam Chang, Jason Chow, Erin Curran, Matthew Dennison, Chris Hogben,

Rachel Kumar, Tom Kutter, Alex Lange, Aaron Lee, Matt Lerner, George Lin, Michael Metzger,

Margaret Morris, Laurie Redding, Colin Rule, Todd Sieber, Clarice Soloway, Brian Sparr,

Mayumi Stroy, Karen Sweetland, Winston Toy, Vicki Vance, Tim Villanueva, Sam Wu,

Harry Xue, and Gray Watson.

Thanks to the PayPal Merchant Technical Support team for your contributions to

and continued support of the PayPal Developer Community.

Finally, thanks to everyone out there building websites, applications, and services

that work with PayPal. Without you, there would be no need for this book in the first place.

Foreword

This is an exciting time for PayPal. Our business has grown exponentially over the past

few years, and we see a tremendous future ahead. PayPal’s developer community is an

important part of our future and will be instrumental in helping PayPal be the global

leader in online payments.

When you build PayPal into a website, you get much more than a payment processing

service. Our commitment to providing the most secure payments platform in the

world is why we employ a team of experts whose responsibility it is to stay one step

ahead of fraudsters. And when problems do arise with a transaction, our dispute resolution

tools and our customer support representatives help both buyers and sellers resolve

issues in a professional manner.

With thousands of businesses turning to PayPal every week to meet their payment

needs, the demand for developers with PayPal expertise grows greater each day. Resources

such as Pro PayPal E-Commerce will help you make informed decisions when choosing

the right payment solution for your or your client’s business.

It is developers like you who will have the next brilliant idea for new, creative uses of

the PayPal platform. We look forward to partnering with you on innovative, cutting-edge

technologies that provide the best user experience for our customers around the world.

Rajiv Dutta

President, PayPal

Table of Contents

Foreword . . . . . . . . . . . . . . . . . . . . . . . xv

About the Author . . . . . . . . . . . . . . . . . . . xvii

About the Technical Reviewer . . . . . . . . . . . . . . . . . . . . . xix

Acknowledgments . . . . . . . . . . . . . . . . . . . . . xxi

Introduction . . . . . . . . .  . . . . . . . . . . . . . . xxiii

CHAPTER 1 Introduction to PayPal

The PayPal Advantage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Increased Sales . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Credibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

The Checkout Experience. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

Digital Money Platform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

PayPal and eBay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Choosing the Right Solution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Website Payments Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Instant Payment Notification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Payment Data Transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

PayPal API . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Payflow Gateway . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Virtual Terminal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Pre-Integrated Solutions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Shopping Carts and Storefronts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Digital Goods Delivery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Accounting and Invoicing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Developer Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Developer Central . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Integration Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

PayPal Developer Community . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Solutions Directory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

PayPalTech . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

PayPalDev.org . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

CHAPTER 2 The PayPal Account

Account Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Personal Account . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Premier Account. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Business Account . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Sandbox Account . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

PayPal Transaction Fees . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Account Status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Verified. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Confirmed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Limited. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Closed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Countries. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Currencies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Account Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Account Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24

Financial Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

Selling Preferences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

CHAPTER 3 Basic Website Payments 

Website Payments Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

The Buy Now Button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Donations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

Subscriptions and Recurring Payments . . . . . . . . . . . . . . . . . . . . . . . . 45

Using the PayPal Shopping Cart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Cart Upload. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Passing the Shopping Cart Total to PayPal . . . . . . . . . . . . . . . . . . . . . 51

Passing Individual Item Details to PayPal . . . . . . . . . . . . . . . . . . . . . . 52

Specifying the Tax for the Shopping Cart . . . . . . . . . . . . . . . . . . . . . . 52

Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

CHAPTER 4 Encrypted Website Payments 

Overview of EWP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Public Key Cryptography. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

Encrypted Code vs. Unencrypted Code . . . . . . . . . . . . . . . . . . . . . . . . 58

How PayPal Reads Encrypted Code . . . . . . . . . . . . . . . . . . . . . . . . . . . 59

Blocking Unencrypted Website Payments . . . . . . . . . . . . . . . . . . . . . . 59

Creating Encrypted Buttons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

EWP with the Button Factory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Creating Certificates and Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

Creating a Private Key and Public Certificate . . . . . . . . . . . . . . . . . . . 61

Uploading a Public Certificate to PayPal . . . . . . . . . . . . . . . . . . . . . . . 62

Downloading the PayPal Public Certificate . . . . . . . . . . . . . . . . . . . . . 63

Encrypting Buttons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

The Encrypted “Blob” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Java Developers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

Windows Developers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68

PHP Developers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

Perl Developers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

CHAPTER 5 Postpayment Processing

Auto Return. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

Auto Return Account Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

The rm Variable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89

Payment Data Transfer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

How PDT Works . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

PDT Account Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

Sample PDT Script. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93

PDT Shortcomings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

Instant Payment Notification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

How IPN Works. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97

IPN Account Settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98

IPN Sample Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99

Dynamically Setting the Notification URL . . . . . . . . . . . . . . . . . . . . . 101

Dispute Resolution with IPN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

Using IPN and PDT Together . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

IPN Troubleshooting Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102

Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103

CHAPTER 6 The PayPal API 

Overview of the PayPal API . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

API Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106

Life Cycle of an API Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

Accessing the PayPal API. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

API Credentials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

API Certificates vs. API Signatures . . . . . . . . . . . . . . . . . . . . . . . . . . . 108

Using API Certificates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109

Third-Party API Calls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

Making API Calls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

Using the SOAP Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

Using the Name/Value Pair Interface . . . . . . . . . . . . . . . . . . . . . . . . . 116

PayPal API Endpoints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

The PayPal SDK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

A Simple Example of Making a PayPal API Call . . . . . . . . . . . . . . . . 119

Handling PayPal API Responses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127

Transaction Management with the PayPal API. . . . . . . . . . . . . . . . . . . . . . 128

Issuing Refunds with the RefundTransaction API. . . . . . . . . . . . . . . 129

Searching Account History with the TransactionSearch API . . . . . 131

Authorizing Payments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135

Sending Money with MassPay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

The Rules of MassPay. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137

The MassPay API . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

File-Based Mass Pay. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

Website Payments Pro . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

Website Payments Pro in the UK. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142

Website Payments Pro in the Rest of the World . . . . . . . . . . . . . . . . 142

Applying for Website Payments Pro . . . . . . . . . . . . . . . . . . . . . . . . . . 142

Direct Payment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143

Express Checkout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149

Canceling Website Payments Pro . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154

Seller Protection Policy for Website Payments Pro . . . . . . . . . . . . . 154

Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154

CHAPTER 7 Payflow Gateway

Payment Gateways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157

Acquiring an Internet Merchant Account . . . . . . . . . . . . . . . . . . . . . . 158

Payflow Pro. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

Getting Started with Payflow Pro . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

Using the Payflow SDK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159

Processing a Credit Card Transaction . . . . . . . . . . . . . . . . . . . . . . . . 160

Testing Credit Card Transactions with the Simulator . . . . . . . . . . . 167

Debugging Common Payflow Pro Errors . . . . . . . . . . . . . . . . . . . . . . 169

Transaction Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

Tender Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

Reference Transactions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 170

Implementing PayPal Express Checkout with the

Payflow Pro API. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171

XMLPay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173

Payflow Link . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176

Creating a Buy Now Button with Payflow Link . . . . . . . . . . . . . . . . . 176

Receiving a Transaction Response from Payflow Link . . . . . . . . . . 177

Testing Payflow Link Transactions . . . . . . . . . . . . . . . . . . . . . . . . . . . 179

Managing a Payflow Link Account . . . . . . . . . . . . . . . . . . . . . . . . . . . 180

PayPal Manager. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180

Logging in to PayPal Manager. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180

Activating a Payflow Account. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181

Generating Reports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182

Using the Virtual Terminal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 182

Managing a Merchant Profile. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184

Performing Manual Captures and Settlements. . . . . . . . . . . . . . . . . 185

Payflow Fraud Protection Services . . . . . . . . . . . . . . . . . . . . . . . . . . . 185

Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189

CHAPTER 8 Reporting

PayPal Reporting Portal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191

Transaction Reconciliation Report . . . . . . . . . . . . . . . . . . . . . . . . . . . 193

Settlement File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194

Daily Sales Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197

Financial Statement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198

Dispute Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202

Searching Payment History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203

Reporting Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205

Opening CSV Report Files in Excel . . . . . . . . . . . . . . . . . . . . . . . . . . . 206

PayPal Manager Reports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208

Transaction Summary Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210

Recurring Billing Transactions Report . . . . . . . . . . . . . . . . . . . . . . . . 211

Filter Scorecard Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213

Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 214

CHAPTER 9 Managing Online Disputes

Establishing Clear Policies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216

Item Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216

Return Policy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216

Shipping Policy. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217

Creating a Resolution Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 217

Managing Your Resolution Plan. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218

Handling Chargebacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219

PayPal Chargeback Specialists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220

Avoiding Chargebacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220

Seller Protection Policy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221

Resolving Disputes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221

PayPal Resolution Center . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222

Resolution Center IPNs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 226

Implementing PCI Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227

PCI Data Security Standard Requirements . . . . . . . . . . . . . . . . . . . . 228

Merchant Levels for PCI Compliance . . . . . . . . . . . . . . . . . . . . . . . . . 228

PCI Compliance Validation Requirements . . . . . . . . . . . . . . . . . . . . . 229

Additional Resources for Disclosure and Compliance . . . . . . . . . . . 230

Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230

APPENDIX PayPal Reference

Standard Variable Reference. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231

The cmd Variable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231

Action Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232

Individual Item Information Variables . . . . . . . . . . . . . . . . . . . . . . . . . 232

Display Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233

Transaction Information Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . 234

Cart Upload Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235

Cart Upload Variables for Individual Cart Items . . . . . . . . . . . . . . . . 235

Address Override Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236

Prepopulating Business Account Signup Variables . . . . . . . . . . . . . 237

PayPal Subscription Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238

IPN and PDT Variable Reference. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239

Buyer Information Variables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239

Transaction Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240

Payment Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240

Currency and Currency Exchange Variables . . . . . . . . . . . . . . . . . . . 242

Auction Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243

Mass Payment Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 243

Subscription Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244

Dispute Notification Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245

API Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245

General API Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245

Authorization & Capture API Error Codes. . . . . . . . . . . . . . . . . . . . . . 246

Direct Payment API Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247

Express Checkout API Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . 253

GetTransactionDetails API Error Codes . . . . . . . . . . . . . . . . . . . . . . . 256

MassPay API Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256

RefundTransaction API Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . 258

TransactionSearch API Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . 259

AddressVerify API Error Codes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260

BillUser API Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260

Payflow Pro RESULT Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261

RESULT Values for Declines and Errors . . . . . . . . . . . . . . . . . . . . . . . 262

RESULT Values for Communication Errors . . . . . . . . . . . . . . . . . . . . 265

Payflow Link Variable Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266

INDEX . . . . . . . . . . . . . . 269

Bookscreen

Introduction

Who This Book Is For

This book is primarily for software developers. I assume you have a basic understanding

of Internet technologies and programming techniques. Code samples are scattered

throughout the text and are provided in numerous languages, so fluency in languages

such as Java and PHP will help you get the most value from the book. All the code samples

in this book, as well as additional code that isn’t included in the text, are provided

in the Source Code/Download section of the Apress website at www.apress.com.

If you are a business owner or entrepreneur with little to no programming experience,

however, there is still a significant amount of information you can glean from these

pages. While a good portion may be too technical for your interest, this book provides

details on almost all PayPal technologies, and as such can give you a better sense of the

type of work that would need to be done in order to integrate PayPal into your grand

schemes, even if you ultimately won’t be the one hacking out the code.

How This Book Is Structured

This book consists of nine chapters and an appendix. The sections that follow offer a general

overview of the content.

Chapter 1: Introduction to PayPal

Chapter 1 provides background information about PayPal and introduces the notion of

PayPal as a platform. Pre-integrated solutions are presented, as well as guidelines for how

to choose the best PayPal solution to meet your needs. The context for the rest of the

book is set in this introductory chapter.

Chapter 2: The PayPal Account

Chapter 2 takes a look at the PayPal account, a distinction that lies at the core of the

PayPal system. It’s what makes the connection between your email address and your

bank account, and it allows you to configure the payment technologies that PayPal makes

available. It’s also through your PayPal account that you are able to generate reports that

detail the success of your business.

Chapter 3: Basic Website Payments

Chapter 3 begins the inquiry into how PayPal can be used to accept online payments.

PayPal’s success can largely be attributed to its ease of use, and the options covered in

this chapter are the source of that reputation. Later chapters cover more advanced technologies,

almost all of which are not as simple to set up and manage as those covered in this chapter.

Chapter 4: Encrypted Website Payments

Chapter 4 takes the notions presented in Chapter 3 and extends them by adding an

optional layer of security via public key cryptography. By using the techniques presented

in this chapter, you can offer payment options on your website that are impenetrable by

hackers and fraudsters.

Chapter 5: Postpayment Processing

Chapter 5 takes a look at what takes place after the transaction is complete. This chapter

covers the popular Instant Payment Notification (IPN) and Payment Data Transfer (PDT)

technologies, which you can leverage to improve the buyer experience and automate

many aspects of your business.

Chapter 6: The PayPal API

Chapter 6 covers the publicly available functionality that PayPal exposes via its API interface.

Both the traditional SOAP and the new Name-Value Pair (NVP) interface are covered.

The API can be used to accept payments, send payments, and perform administrative

duties such as issuing refunds and searching transaction history.

Chapter 7: Payflow Gateway

Chapter 7 covers the Payflow Pro and Payflow Link payment solutions that PayPal acquired

with its purchase of the VeriSign Payment Services business in 2005. These gateway services

can optionally work with an external processor (other than PayPal), to establish the Internet

Merchant Account (IMA) necessary to process credit card transactions.

Chapter 8: Reporting

Chapter 8 presents the array of reporting functionality that PayPal offers. These primarily

include the reports provided in the business-reporting portal; for Payflow merchants, this

includes the reports provided in PayPal Manager.

Chapter 9:Managing Online Disputes

Chapter 9 discusses best practices for reducing your risk of becoming a victim to fraudulent

transactions. This chapter also covers the PayPal Resolution Center, an area on the

PayPal website where buyers and sellers can communicate and attempt to resolve disputes amicably.

Appendix: PayPal Reference

The appendix contains reference material that can be used during development to

quickly look up the meaning of a particular variable or error code, for instance.