Follow-up to the comprehensive payment-system review. Fixes the issues the
review found in the initial integration, plus the rough edges it introduced.
Money-safety:
- Replay-by-key now replays the FULL original request verbatim from a stored
square_request_snapshot, so a retained idempotency key returns the original
payment instead of IDEMPOTENCY_KEY_REUSED (previously the row sat pending
forever). IDEMPOTENCY_KEY_REUSED remains ambiguous (never proof of no charge).
- Dev mock mirrors real Square for unknown-key replays: ccof: saved-card
sources are charged and rescued; spent cnon: nonces surface
ErrReplayKeyNotRetained. (Fixes dev/prod parity divergence.)
- Webhook dedup row committed AFTER dispatch (at-least-once); FAILED till sales
claw back gift-card funding; event-type strings match Square's real catalog.
- Expired-gift-card cancellation refunds set creditFailed (never a phantom
'completed' refund); cancellation refunds lock all payment rows ascending.
- Sweep never rescue-completes a gift-card purchase without delivering the card.
- Tip no-client-key fallback is a deterministic count-based key under the
booking advisory lock (retry-safe, distinct tips don't collapse).
- M-cap subtracts completed refunds, clamped to [0, total].
2FA (PSD2 SCA stand-in) for online saved-card payments:
- Full feature: status/setup/verify/disable endpoints, gating helper wired into
all 7 saved-card charge paths (incl. BuyGiftCard + admin saved-card), account
admin-tab settings UI, frontend gating across all payment surfaces.
- Enforcement is FAIL-CLOSED: on unless REQUIRE_2FA=false or an explicit
mock/dev SQUARE_ENVIRONMENT; startup warning when off in a non-dev env.
- Verify is brute-force hardened (5-attempt lockout, timing-safe compare);
plaintext codes only logged when enforcement is off (dev).
- GDPR: anonymize_user also scrubs 2FA columns and staff notes.
Infra/docs:
- nginx: /api/ response cache removed (cross-user disclosure); port 80
redirects to HTTPS (localhost/RFC1918 exempt, end-anchored regexes); HSTS;
separate webhook rate-limit zone.
- Schema: users 2FA columns; payments/till_sales square_source_id +
square_request_snapshot.
- Legal docs: gift-card cooling-off, international-transfers section, tips
policy; Gap Backlog P3 webhooks marked done; stale counts/wording corrected.
- Flaky test race fixed (t.Parallel + global mock mutation); suite 26/26
packages green, 2,142 tests, svelte-check clean.
Gift-card rolling expiry (setting-driven, was dead config):
- GetGiftCardExpiryMonths(): single source of truth (business_settings
gift_card_expiry_months, fallback 24) shared by payment handlers and the
CleanupExpiredGiftCards job (was hardcoded 24).
- expiry_date now maintained on ALL 9 gift-card write sites (buy, topup,
transfer, redeem, terminal payment, refund credit, till) so the refund-time
guard at refunds.go actually fires. Schema default 12->24 + migration note;
test-DB seed aligned. Stale "expiry_date IS NULL" test rewritten; new
expired-card-rejected regression test.
Frontend SvelteDate purge (docs' stated convention, wide):
- All 180+ raw `new SvelteDate(...)` uses across routes/components replaced
with parseWallClockDate (backend UTC ISO) or new Date (wall-clock
constructors). SvelteDate imports removed. timeSlots.ts getDayWithOrdinal
fixed. Zero SvelteDate references remain; svelte-check clean.
Strict timezone/DST testing + QA fixes:
- 8 new hermetic boundary tests: clock.DST transitions (both 2026 folds),
closing-hours GMT vs BST, booking date-window midnight, refund-tier
elapsed-time independence, deposit-window UTC-instant, scheduling
LondonDateString midnight, today AT TIME ZONE window + UTC round-trip.
- today.go summary date labels fixed to London wall-clock (were showing the
previous UTC day during BST) + regression test.
- pgx ScanLocation fixed to UTC via AfterConnect (was host-local -> JSON
offsets depended on deployment TZ, contradicting the documented UTC
invariant) + regression test. Registered as a new *Type to avoid a data
race on the shared type map (caught by -race).
Admin Business Settings (setting now functional => legal floor):
- gift_card_expiry_months validation floor raised 1 -> 12 months (CMA/
Consumer Rights Act 2015 unfair-contract-term guidance) in endpoint + UI,
with rolling-expiry semantics shown in both display and edit form.
- 3 new expiry validation tests; 2 pre-existing message assertions updated.
Full suite 25/25 + race clean via run-tests.sh lockfile; svelte-check 0
errors/warnings; production build succeeds.
N1 (HIGH) — BuyGiftCard concurrent same-key retry could double-issue gift
cards (2× value for 1 charge). Added pg_advisory_lock on the idempotency key
(mirroring the tip pattern) acquired before the idempotency check, so
concurrent same-key retries serialize and only one executes gift-card
creation.
N2 — Amount-equality guards in both reuse branches (CreateTipPayment and
BuyGiftCard). A same-key retry with a different amount now returns 400
instead of silently mutating the pending record's books/VAT/refund caps.
N3 — test coverage:
- TestBuyGiftCard_RetryPending_ReattemptsCharge: pending record + same-key
retry re-attempts, reuses the record (count=1), completes, and issues the
gift card exactly once.
- TestCreateCheckoutHTTP_DeviceOptionsWireShape: httptest.Server asserts
device_id is under checkout.device_options (not top-level). Extracted
createCheckoutHTTPWithClient for injectable base URL.
- MockClient.CreatePayment now dedups on idempotency key (paymentByKey map),
matching real Square behaviour.
N4 — Corrected the savepoint comments in handlers.go and giftcards.go: the
savepoint only exists in the test harness; in production db.Conn.Begin is a
plain tx and the status UPDATE runs on a separate pooled connection. Commit
is a harmless no-op in prod but required in tests.
Bonus bug fixed: CheckIdempotencyByKey scanned NULL booking_id/gift_card_id
(gift-card purchases) into plain string, failing with 'cannot scan NULL'.
Now uses sql.NullString.
Docs: Technical Manual.md:53 and Feature Catalog.md (2.1, 2.5) corrected —
no longer claim Web Payments SDK is live; new-card entry is documented as
pending P11, saved-card flow works via ccof tokens, dev mock rejects raw PANs.
New test files cover previously untested paths across DAV, validators,
S3, Square, mw, bookings, user, and payments packages.
Includes mock fix: HoldCheckouts flag on MockClient allows tests to
pause auto-complete goroutine for testing PENDING checkout states.
Coverage: 50.4% → 65.0% (+14.6pp)
Refactor BuyGiftCard to insert pending payment before Square call with VAT applied. Add transaction wrapping to gift card handlers. Remove redundant Content-Type header sets. Migrate all time.Now() to clock.Now().
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Migrate all test files from SetupTestDB/db.DB pattern to per-test transactions:
- Replace SetupTestDB(t) with SetupTestTx(t) for context + transaction
- Replace db.DB.Query/QueryRow/Exec with tx.Query/QueryRow/Exec
- Replace context.Background() with context from SetupTestTx
- Replace defer rows.Close() pattern with explicit rows.Close()
- Add testdb.SeedBaseline(pool) to all TestMain functions
- Wire db.Conn = db.NewPoolProxy(pool) in all TestMain functions
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
- Added generic formatAndPreserveCursor() helper on frontend to track
and restore selection caret position during dynamic input sanitization
- Applied to all card inputs, gift card code inputs, and expiry inputs
- Added Luhn validation (isValidLuhn) for saved cards and gift cards
- Rebuilt payments test DB and got 100% green tests