This service mimics the real OPP (One Payment Platform) payment gateway so the platform's
full payment flow;
— initialise → hosted checkout → webhook → capture —
can be exercised in SIT without a working real OPP instance. See the
README
for the full integration contract.
Selectable on the hosted checkout page — last 4 digits shown indicate the scenario:
| Card | Authorisation | Capture |
|---|---|---|
| Visa •••• 0000 — Approved | Approved | Approved |
| Mastercard •••• 0001 — Approved | Approved | Approved |
| Visa •••• 0002 — Declined at authorisation | Declined | Declined |
| Visa •••• 0003 — Authorised, capture fails | Approved | Declined |
Initialising a transaction for exactly 50 minor currency units (e.g. 50p) suppresses webhook delivery entirely, to let QA exercise payment timeout paths.