feat(wallet): add wallet entities and repository

Entities for the four wallet tables and a WalletRepository that the wallet
processor will build on (PC-103).

Every method goes through the caller's transaction, and writes and locks
refuse to run without one: outside a transaction a lock is released as soon
as it is taken and a balance could move without its ledger row.

- LockWallet creates the wallet on first use, taking the organization from
  the customer, then locks it with SELECT ... FOR UPDATE.
- LockWallets always locks in customer_id order so opposite transfers
  cannot deadlock.
- AddBalance and ConsumeLot are conditional updates that return an error
  when they would overdraw, instead of tripping the CHECK constraint.
- ListActiveLots returns unexpired lots with balance in K9 spending order.

The tests need a real Postgres and run only when TEST_DATABASE_URL points at
a migrated database. Both the lock and the lock ordering were checked by
removing them and watching the tests fail (lost update, deadlock detected).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

This commit is contained in:

efrilm

2026-09-30 01:01:03 +07:00

co-authored by

Claude Opus 5.5

parent b107f4ef04

commit fc5eecb68a

5 changed files with 776 additions and 0 deletions

									
										internal/entities/entities.go
									
		+5
		
												View File
												
				@@ -44,6 +44,11 @@ func GetAllEntities() []interface{} {

						&ProductOutletPrice{},

						&Expense{},

						&CashAdvance{},

						// Wallet entities

						&CustomerWallet{},

						&WalletTransaction{},

						&WalletLot{},

						&WalletLotAllocation{},

					}

				}