Salesforce Billing Payment Gateway Interfaces

A payment gateway package requires three interfaces to communicate with Salesforce Billing. Each interface contains methods that the user-defined PaymentGatewayAPI class implements to process different types of transaction actions.

Creating a PaymentGateway Interface

The PaymentGateway interface contains several basic transaction methods that the PaymentGatewayAPI class implements to handle gateway requests. The methods allow PaymentGatewayAPI to create a credit card token, process a payment charge, void a payment, authorize a payment, and refund a payment.
Creating a PaymentGateways Interface

The PaymentGateways interface uses the processPayments method, which evaluates the payment transaction’s type to perform a payment action.
Creating a PaymentGatewayStatus Interface

Salesforce Billing implements the PaymentGatewayStatus interface to populate the TransactionResult’s GatewayStatus enum with the value of the return code that the external gateway set in transactionResult.