You will need to set up a callback URL where you want to register the intercepted responses. Using Fusion APIs, you can configure an interceptor by adding this URL against the supported intercepting points. See Configure Interceptors for more info.
Can I configure multiple Interceptors?
Yes, you can. In this release, Fusion allows you to configure Interceptors only on Resource Products. The allowed intercepting points are the two payment states mentioned below:
PAYMENT_REQUESTED - When a payment request comes into the Fusion System.
PAYMENT_AUTHORIZATION_RECEIVED - After the payment authorization check is complete.