2012

Name-Value Pair API Developer Guide August 2012 19
PayPal Name-Value Pair API Basics
Creating an NVP Request
1
Specifying an API Credential Using Signatures
You must specify API credentials in each request to execute a PayPal API operation. You can
use either a signature or a certificate, but not both.
When you execute a PayPal API operation, you use credentials, such as a signature, to
authenticate that you are requesting the API operation. The following diagram shows the API
credentials part of an NVP request:
IMPORTANT: You must protect the values for USER, PWD, and SIGNATURE in your
implementation. Consider storing these values in a secure location other than
your web server document root and setting the file permissions so that only
the system user that executes your ecommerce application can access it.
To enable PayPal to authenticate your request:
1. Specify the API username associated with your account.
USER=
API_username
2. Specify the password associated with the API user name.
PWD=
API_password
3. If you are using an API signature and not an API certificate, specify the API signature
associated with the API username.
SIGNATURE=
API_signature
4. Optionally, you can specify the email address on file with PayPal of the third-party
merchant on whose behalf you are calling the API operation.
SUBJECT=
merchantEmailAddress
NOTE: Typically, a merchant grants third-party permissions to a shopping cart. The merchant
previously must have given you permission to execute the API operation.
Specifying Credentials Using cURL
The following example shows one way to specify a signature using cURL: