max / makenotwork

payments: document idempotency storage is consumed by the global middleware The idempotency.rs functions are the storage layer for metrics::idempotency_middleware (the global POST/PUT replay guard) and are exercised by tests/workflows/idempotency.rs (6 adversarial tests). The audit twice misread the module as unwired/untested because the consumer lives in the middleware layer, not the payment routes; name it in the module doc so the wiring is discoverable and additive to the structural checkout dedup index. ultra-fuzz Run 5 M-Pay1 (deep). Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: Max Johnson <me@maxj.phd> · 2026-06-24 02:12 UTC

Commit: 5a31ce3a38b6fb14a38ed05efee97d5e66183a1c

Parent: f562a1f

1 file changed, +11 insertions, -0 deletions

M server/src/db/idempotency.rs +11

			@@ -1,4 +1,15 @@
1	1		//! Idempotency key storage for safe POST retries.
	2	+	//!
	3	+	//! These functions are the storage layer for [`crate::metrics::idempotency_middleware`],
	4	+	//! the global POST/PUT replay guard mounted on the router: it reads
	5	+	//! [`get_cached_response`] before running a handler and writes [`store_response`]
	6	+	//! (fire-and-forget, via the background pool) on a successful 2xx/3xx response,
	7	+	//! scoped to `(key, user_id, method, path)`. The scheduler calls
	8	+	//! [`cleanup_expired`] on its daily tick. This is distinct from — and additive
	9	+	//! to — the structural checkout dedup (the `(buyer_id, item_id) WHERE
	10	+	//! status='pending'` partial unique index): the index makes a double checkout
	11	+	//! unrepresentable; this cache replays the response of any retried POST/PUT.
	12	+	//! Exercised end-to-end by `tests/workflows/idempotency.rs`.
2	13
3	14		use sqlx::PgPool;
4	15		use crate::db::UserId;