Reserve Account Number Adapter

Generic adapter for reserving a bank account number in the core banking system before a loan is established.

Reserve Account Number

POST /reserve-account-number — Reserve an existing account number in the core banking system for a loan being established.

Called once per loan (multi-instance service task) after the customer accepts a loan offer.

Design Notes

Why multi-instance? A financing agreement can contain several loans (e.g. a repayment loan and an interest-only loan). The service task runs once per loan so each gets its own reserved account number independently.

Why Id for idempotency? Network failures or retries may cause the same request to reach the adapter more than once. Using the loan's external identifier as an idempotency key ensures a second call returns the same reserved account number rather than reserving a new one.