Integration Guide

Table Of Contents
Express Checkout Integration Guide October 2009 33
PayPal Name-Value Pair API Basics
Executing NVP API Operations
3
Executing NVP API Operations
You execute an PayPal NVP API operation by submitting an HTTP POST request to a PayPal
API server.
Specifying a PayPal Server
You execute a PayPal API operation by submitting the request to a PayPal API server.
To execute a PayPal NVP API operation, submit your complete request to one of the following
end points:
NOTE: You must use different API credentials for each kind of server. Typically, you obtain
API credentials when you test in the Sandbox and then obtain another set of
credentials for the production server. You must change each API request to use the
new credentials when you go live.
Logging API Operations
You should log basic information about each PayPal API operation you execute.
All responses to PayPal API operations contain information that may be useful for debugging
purposes. You should log the Correlation ID, which identifies the API operation to PayPal,
and response-specific information, such as the transaction ID, which you can use to review a
transaction on the PayPal website or through the API. You can log other information that may
be useful, such as the timestamp. You could implement a scheme that logs the entire request
and response in a “verbose” mode; however, you should never log the password from a
request.
Server end point Description
https://api-
3t.sandbox.paypal.com/nvp
Sandbox server for use with API signatures; use for testing your
API
https://api-3t.paypal.com/nvp PayPal “live” production server for use with API signatures
https://api.sandbox.paypal.com/nvp Sandbox server for use with API certificates; use for testing
your API
https://api.paypal.com/nvp PayPal “live” production server for use with API certificates