Money-safety idempotency hardening (I1, wide):
- validate:"max=45" on CreateTerminalPayment/BookingPayment/Refund/Tip/
BuyGiftCard idempotency keys (all feed Square's 45-char /v2/payments,
/v2/refunds, /v2/cards caps); BuyGiftCard corrected from a wrongly-loose
max=64. Till keeps max=64 (its key also feeds the 64-char terminal-checkout
endpoint).
- Explicit 45-char guard in RefundPayment: the one handler that decodes
RefundRequest without running the struct validator, so the tag alone was
inert; a longer key would 400 at Square and be misclassified as a
definitive refund decline.
- New TestIdempotencyKey_OverLength_RejectedAcrossPaymentHandlers covers all
six endpoints (terminal saved-card, booking, tip, gift-card, till, refund).
Stable-sentinel card identity in idempotency keys (C1, wide):
- BookingFlow deposit key now uses the 'new-card' sentinel instead of
embedding the cnon: nonce (matches UserPaymentModal/account). A re-tokenize
after a spent nonce no longer regenerates the key, closing a lost-response
double-charge window.
- TipPayment + UserBookingModal tip keys now include card identity
(selectedCardId || 'new-card'); previously keyed on amount only, so a
same-amount tip on a DIFFERENT card reused the key and deduped a distinct
charge. Resets cleared in every success/close path.
Test isolation (R1): TestRefund_PendingResume_NewKeyAfterModalReopen no
longer t.Parallel — it swaps the package-level SquareClient mid-test and a
concurrent parallel test could observe the swapped instance.
Naming/quality (M1/M2/M4): resolveChargeSource local renamed savedRowID (was
shadowing the cardID *string parameter); BuyGiftCard fallback prefix
"till-" -> "gc-"; saved-card terminal response key "checkout_id" -> "payment_id"
(it holds a DB payment row, not a Square checkout) with matching frontend
fallback. README maintenance-job count corrected 24 -> 25.
Full suite 25/25 + race clean via run-tests.sh lockfile; svelte-check 0
errors/warnings; production build succeeds.
Money-safety idempotency fixes (external review bugs 1-3):
- processChargeGroup: aggregated refund key now hashes the sorted pending-row
set (chargeID-square-agg-<sha256 suffix>) so a changed group can never mark
a new row completed against an old smaller refund; >45-char chargeIDs use a
hashed prefix instead of verbatim truncation (which would collide charges on
Square's global key dedup). Same-set crash-retry keeps Square's dedup.
- CreateTerminalPayment saved_card: two-tier idempotency key — client-supplied
per-attempt UUID preferred (distinct identical charges no longer collapse),
deterministic booking+type+amount+card fallback for no-key retry safety.
PaymentModal sends a per-charge UUID cleared after success.
- ensureRefundKey: legacy NULL-key manual refunds persist a generated key to
the row BEFORE the Square call (race-safe AND idempotency_key IS NULL guard),
so a lost-response retry reuses the key and never double-refunds. Wired into
resumeManualPendingRefund and the sweep's manual-retry loop.
Classification + money-safety hardening:
- till.go/sweep.go: structured square.ErrorCode/IsNotFound are authoritative
when present; message-substring matching only for non-structured errors
(dev mock, client-side status errors). Fixes fragile string-matching driving
sweep retries and gift-card clawbacks.
- SaveCardForUser: ON CONFLICT (user_id, square_card_id) DO NOTHING + re-select
(was a latent UNIQUE-violation 500 on save-card retry).
- CreateBookingPayment: partial payments re-validated against remaining balance
inside the advisory lock (closes concurrent-overpayment race).
- InvalidateSquareCustomerCache on GDPR erasure paths (account.go,
time-blockers.go stale-guest anonymization).
- GetUserGiftCardBalanceAdmin: in-handler admin check (defense-in-depth).
- getCheckoutHTTP: warn on multi-payment checkouts instead of dropping
payments[1:].
- Cash/giftcard terminal branch: removed dead idempotency SELECT, "tip-" ->
"till-" prefix.
- UserPaymentModal: removed vestigial polling state; proper interval cleanup.
- account/+page.svelte: gift-card redeem dialog links /terms.
- nginx CSP: allow *.squarecdn.com and js.squareup.com so the Square Web
Payments SDK + card iframe can tokenize behind the proxy.
Tests: +8 regression tests covering changed-set refund keys, legacy NULL-key
single-refund, saved-card client-key dedup/no-dedup, concurrent partials, and
cache invalidation. Full suite + race detector clean via run-tests.sh lockfile.
TransferGiftCard locked source-then-destination in caller-chosen order, so concurrent cross-transfers (A→B and B→A) acquired row locks in opposite orders and deadlocked (SQLSTATE 40P01), aborting one transfer with a generic 500. Both rows are now locked in lexicographically sorted ID order (case-insensitive, matching the 12-hex mixed-case card codes), with the scanned values mapped back to source/destination roles afterward. Adds a deterministic concurrency regression test that holds both row locks on dedicated connections to force the AB-BA cycle, proving the old code deadlocks and the new code serializes cleanly.
Till sales and gift-card purchases now use uniqueChargeKey and resolveChargeSource/chargeFailureStatus instead of duplicated inline logic. The saved-card delete path logs the square_card_id through square.TokenPrefix so full ccof references never reach logs.
BuyGiftCard and till online_square charge the cnon: nonce directly (no synthetic card-on-file); BuyGiftCard.IdempotencyKey is now validate-required (empty key previously collided on the UNIQUE constraint). Saved-card branches forward customer_id and lazily provision legacy cards. lockCancellationPayments uses the deliberately-blocking xact lock so a cancellation never silently drops a refund under contention (admins see the full manual refund round-trip).
R1/R4: saved_card branch in CreateTerminalPayment now mirrors CreateTipPayment
- advisory lock (crussell:payment:<bookingID>) serializes concurrent double-clicks
- deterministic key bookingID-sc-type-amount-cardID (<=45 chars) so a lost-response
retry derives the same key and dedups instead of double-charging
- idempotency switch inside the lock: completed -> dedup, pending -> reuse with
pence amount-guard, failed -> clean 409
- success response includes card_brand/card_last4 (frontend already reads them)
R2: add 'failed' case to all four retry switches (tip, booking, gift card, till)
- a swept/definitively-rejected record returns 409 instead of 500-ing on the
idempotency_key UNIQUE constraint
R3: extend SweepStalePendingPayments to till_sales card rows
- sweeps pending till_sales (online_square/in_person_card) past Square's ~24h
key retention, closing the double-charge window for till sales
- swept rows logged with the same CRITICAL manual-reconciliation marker as the
refund sweep
Webhook fail-closed: reject 503 when SQUARE_WEBHOOK_SIGNATURE_KEY unset, 403 on
bad signature (was: skip verification in dev)
Refund status resolution: refunds now resolve by Square status
(COMPLETED/PENDING/FAILED/REJECTED) instead of assuming completed; real error
codes (REFUND_AMOUNT_INVALID, PAYMENT_NOT_REFUNDABLE, REFUND_ALREADY_PENDING)
added to the definitive/processed classification
HTTP client: CreateCard key truncated to <=45 chars, device_options always sent
(env SQUARE_TERMINAL_DEVICE_ID fallback), processing_fee reads amount_money,
ListCards cursor loop, refund keys hashed to <=45 chars
Other fixes: payment/till/gift-card advisory-lock + FOR UPDATE asymmetries,
GetPaymentByID NULL scans, loyalty redemption lock, card upsert on conflict,
mock ccof: prefix parity, IsValidSquareCheckoutID for real Square IDs,
isAdminRequest defense-in-depth on all 6 admin payment handlers, webhook
signature docs, M8/L5 debug markers removed
Docs: README/FC/TM/Overview updated (22 jobs, 20 CRITICAL sites, 23-section
GDPR export, sweep jobs, webhook fail-closed); P11 plan marks remaining items
(sandbox smoke test, M-8 customer_id, saved-card key dedup trade-off) as
deferred with rationale; gap backlog pruned of completed items
P0 — float truncation: applied math.Round to all remaining int64(x*100)
sites (till penceAmount, refund over-refund guard, GetAlreadyRefundedAmount,
payment summary conversions). A £1.14 till sale previously charged 113p.
P0 — raw PAN stopped at the API edge:
- Deleted CardNumber/CardExpMonth/CardExpYear/CardCVC from TillSaleRequest
and CardNumber/Expiry/CVC from CreatePaymentMethodRequest. Both now accept
card_token (Square nonce) and return 400 when absent. PAN+CVV no longer
transit the application server (PCI-DSS SAQ-A scope).
- Deleted CreateCardOnFileRaw from the SquareClient interface and all
implementations (MockClient, ProdClient, devProdClient).
- Added idempotency_key column to refunds table (UNIQUE).
P0 — RefundPayment hardened: advisory lock on payment ID (prevents two
concurrent refunds passing the over-refund guard), pending-refund-record-
then-Square pattern (scheduler reprocesses on failure), same-key dedup.
P1 — till sale pending-retry now re-attempts the Square charge instead of
returning the stale 'pending' status (gift card was already funded in the
committed tx — silent money loss otherwise). Sale row reused, not duplicated.
P1 — idempotency key caching in frontend: BuyGiftCard and
UserPaymentModal/BookingFlow now cache the key per amount+card, regenerated
on change and cleared on success — matches the tip-flow pattern so a
lost-response retry dedups instead of double-charging.
P1 — CreateTerminalPayment cash/giftcard INSERTs now persist idempotency_key.
Key is unique per payment (booking+type+amount would wrongly dedup two
legitimate identical payments, e.g. two £50 cash receipts).
P1 — gift-card codes no longer logged (spendable credential; value+recipient
only).
Tests: till pending-retry re-attempt, refund same-key dedup, mock CreatePayment
idempotency dedup, CreatePaymentMethod nonce happy path + raw-PAN rejection,
till online_square card_token required/valid.
The pending-retry amount guard compared pence via int64(pounds*100),
which truncates instead of rounding. For non-exact pound values (e.g.
£1.14 stored as the float64 1.1399999999999999) the truncation yields
113 != 114, falsely rejecting a legitimate same-amount retry with 400.
Since the frontend reuses the idempotency key on same-amount retries,
every retry was rejected, permanently stranding the pending record
(and any orphaned Square charge) with no recovery path.
Fix: compare in pence via math.Round — the existing pattern already
used in refunds.go — so non-exact values round to the true pence.
Also applied the same correction to the sibling lossy conversions:
- CreateTipPayment / CreateBookingPayment completed-dedup responses
(would have reported 113p for a 114p payment)
- BuyGiftCard retry amount guard (latent: £10/£20/£50 are float-exact
so it never bit, but the identical trap is now closed)
Tests:
- TestTipPayment_RetryPending_NonExactAmountSucceeds: 114p pending
record + same-amount retry completes and charges 114p (failed on the
old truncation with 400)
- TestTipPayment_RetryPending_AmountMismatchRejected: a same-key retry
at a different amount is still rejected with 400 and the pending
record is left untouched
Verified: full backend suite green (25/25 packages, 0 failures),
-race clean on handlers/payments, go build + go vet clean.
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.
CRITICAL — same-amount tip retry silently never charged:
- CreateTipPayment idempotency check now only short-circuits when the
existing record is 'completed'. A 'pending' record (previous Square call
failed) is REUSED and the charge re-attempted with the same key (Square
dedups safely), instead of returning the stale pending record as 200 with
a success toast and no charge.
- Same fix in BuyGiftCard: pending records trigger a re-attempt, not a
false-success response. Unique idempotency_key constraint means the
pending record must be reused, not re-inserted.
- Fixes the savepoint/rollback interaction: the nested tx (savepoint) is
now committed in the reuse path so the deferred rollback doesn't undo the
later status UPDATE on the same connection.
- Regression test: TestTipPayment_RetryPending_ReattemptsCharge verifies a
pending record + same-key retry re-attempts and completes, reusing the
record (count stays 1).
MAJOR — terminal checkout wire contract:
- device_id now sent as checkout.device_options.device_id (Square's required
shape), not a top-level field which Square rejects with 400.
- 'checkout pending' detection now uses typed sentinel ErrCheckoutPending
with errors.Is in both handlers, matching mock and real HTTP client.
MAJOR — exp_month/exp_year omitted from card creation payload when unset
(now *int with omitempty) — Square would 400 on 0/0; expiry comes from the
tokenized source.
Docs:
- README payments/infrastructure sections corrected (Web Payments SDK claim
replaced with accurate P11-backlog note; dev mock parity described)
- Future Work P11 updated to reflect raw-PAN rejection is now enforced in
both mock and prod (new-card flows are a documented dead end)
- Added plans/p11-square-web-payments-sdk.md: full implementation plan +
handoff prompt for the agent picking up P11 (Web Payments SDK nonces)
Money-moving fixes:
- Tip idempotency key regenerates when the tip amount changes after a failed
attempt (all 3 tip flows). Cached key still reused on same-amount retry
(dedup intact) and cleared on success/modal reset. Prevents silent
under-charge when a user retries at a different amount.
- Till replay path returns actual till_sales.status (may be 'pending') instead
of hardcoded 'completed' — no more misreported successful charge.
- BuyerEmail wired for CreateBookingPayment, gift card purchases, and till
sales (saved_card + online_square), matching the tip flow. Email lookup
errors logged, non-fatal.
- Till buyer-email errors now logged (was silently swallowed).
- on_the_house till top-up uses cached getIdempotencyKey() for retry-safe dedup
(was fresh crypto.randomUUID()).
Test/validation fixes:
- Add TestPaymentFromSquare_* unit tests (else-branch + nil card details),
build tag relaxed to 'test' so they run in the standard dev suite.
- Add TestValidateCardInfo table test (7 cases: both/either/neither/empty).
- Add TestCreateTillSale_TwoIdenticalCreateSales_BothSucceed regression test.
- Remove dead mock pre-registration in TestTipPayment_WithSavedCard.
- Correct misleading till regression-test comment.
ESLint cleanup (12 errors -> 0):
- Remove unused loadingCards in tip + pay-tip pages (dead assignments in
loadSavedCards).
- Scoped eslint-disable for {@html} in CardBrandIcon (hardcoded brand SVGs).
- Remove dead confirmSaveDefaultHours + unused rescheduleVersion prop in
WeeklySchedule (and its parent pass-through).
- Replace new Date() with SvelteDate in WeeklySchedule + BusinessHours.
- Fix each-block key in BusinessHours skeleton loader.
- Use void expression for reactivity-tracker reads in effects.
Admin no longer receives a notification when someone buys a gift card for a friend. The recipient email and gift code are logged for future SMTP delivery instead.
Restore processImage (images.go) and nonDepositPaymentType (handlers.go) with //nolint:unused — used in test files.
Fix 97 tx.Rollback defers to silently discard expected "tx is closed" error after commit.
Frontend: remove 44 unused shadcn-svelte files, 2 dead components, 9 stale npm deps, prune unused exports.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
errcheck: add proper error handling with slog.Error for tx.Rollback, key generation, and s3/dav operations. Add nolint comments for intentionally discarded DB scan errors and HTTP write errors.
unused: remove dead code (svcRow type, processImage, nonDepositPaymentType, generateSecureCode, colorBold, nGreen, nRed)
gosimple S1021: merge var declaration with assignment in manage.go
ineffassign: remove dead assignments in settings.go, till.go, images.go
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
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>
Track voucher_type_at_purchase on gift card creation. Apply VAT at gift card purchase (SPV), at redemption (MPV). Use transaction-aware GetCardByIDQuerier for till saved card lookups. Apply VAT to all booking payments (split records, terminal, tip, checkout). Add TotalVATAmount and TotalNetAmount to PaymentSummary responses.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Replace direct *pgxpool.Pool usage with PoolProxy wrapper across the entire backend:
- db.DB renamed to db.Conn (*pgxpool.Pool -> *PoolProxy)
- JWT functions now accept context.Context instead of using context.Background()
- Handler DB calls route through PoolProxy for per-test transaction support
- Fixture/helper/testdb functions accept Querier interface for decoupling
- Query ordering fixed in bookings handlers: COUNT after data query to avoid pgx conn busy
- Time truncation fixed: time.Date instead of Truncate(24*time.Hour) for week start calc
- testmain_test.go files updated with SeedBaseline and NewPoolProxy
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