Study Guide
Table Of Contents
- PayPal Certified Developer Program Study Guide
- Contents
- List of Tables
- Online Payment Processing
- Internet Security and Fraud Prevention
- Why Every Business Should Be Concerned About Internet Fraud
- Liability for Internet Fraud
- Internet Fraud: What It Is and How It Happens
- Who Is at Risk for Online Fraud
- Reducing Exposure to Fraud
- What Banks and Card Associations Are Doing to Prevent Online Credit Card Fraud
- What PayPal Is Doing to Protect Your Business Against Fraud
- Disclosure and Compliance
- PayPal Fraud Protection Services
- Review Questions
- Getting Started With Account Setup
- API Credentials
- Name-Value Pair (NVP) API
- Express Checkout
- Direct Payment API
- Transactions
- Sandbox Testing
- Answers to Review Questions
- General Reference Information
- Glossary
- Index
Name-Value Pair (NVP) API
Technical Details
5
54 March 2008 PayPal Certified Developer Program Study Guide
Create and Post the Request
Create an NVP request string, and post it to the PayPal server. Add code to the web application
to do the following tasks:
1. Encode the name and value parameters in the request, to ensure the correct transmission of
all characters. This is described in “URL Encoding” on page 55.
2. Construct the NVP API request string, as described in “NVP Format” on page 54 and
“Request Format” on page 56.
3. Post the NVP request to the PayPal server, as described in “Posting Using HTTPS” on
page 58.
Interpret the Response
PayPal processes the request and posts back a response in NVP format. Add code to the web
application to do the following tasks:
1. Decode the name and value parameters in the response.
2. Parse the NVP API response string, as described in “NVP Format” on page 54 and
“Response Format” on page 57.
3. Take appropriate actions based on successful and failed responses.
Technical Details
This section describes details of the technologies used by the NVP API.
Request-Response Model
When using the NVP API, the application posts a request to PayPal, and PayPal returns a
response.
URL Format
The request and response are in URL-encoded format, which is defined by the Worldwide
Web Consortium (W3C). URL is defined as part of the URI specification.
NVP Format
NVP is a way of specifying name-value pairs in a string.
An NVP string conforms to the following guidelines: