Flow

1. Create a Fintecture account
2. Register a client application and get the credentials (i.e the app_id and app_secret) associated to it
3. Encode your credentials using Base64 (Basic base64({app_id}:{app_secret})) to generate the Authorization header
4. Request an access token using your credentials, the customers scope and the Authorization header
5. Extract following information from provided response body:
   • access_token is to be used for endpoints' calls
   • expires_in allows you to know token's duration validity
6. Use access_token for every payment endpoint requiring Bearer
7. Check regularly expires_in and before access token's expiration, ask for a new one