2009

PayPal NVP API Overview
Technical Details
14 08 April 2009 Name-Value Pair API Developer Guide
z The server address in the URL. (See “Posting Using HTTPS” on page 18.)
z API credentials you set up in “Set Up API Credentials” on page 13.
Technical Details
This section describes details of the technologies used by the PayPal NVP API.
Request-Response Model
When you use the PayPal NVP API, you post an NVP request to PayPal, and PayPal posts
back an NVP 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. Find out more about URI
at
http://www.w3.org/Addressing/.
NVP Format
NVP is a way of specifying names and values in a string. NVP is the informal name for the
query in the URI specification. The NVP string is appended to the URL.
An NVP string conforms to the following guidelines:
z The name is separated from the value by an equal sign (=). For example:
FIRSTNAME=Robert
z Name-value pairs are separated by an ampersand (&). For example:
FIRSTNAME=Robert&MIDDLENAME=Herbert&LASTNAME=Moore
z The values for each field in an NVP string are URL-encoded.
URL-Encoding
The request and response are URL-encoded. URL-encoding ensures that you can transmit
special characters, characters that are not allowed in a URL, and characters that have special
meaning in a URL, such as the equal sign and ampersand. For example, the following NVP
string:
NAME=Robert Moore&COMPANY=R. H. Moore & Associates
is URL-coded as follows:
NAME=Robert+Moore&COMPANY=R%2E+H%2E+Moore+%26+Associates
Use the following methods to URL-encode or URL-decode your NVP strings: