LuTiao Programming

Sep 22, 2026 · Backend Development

Beyond Distributed Locks: Three-Layer Idempotency for Spring Boot Order APIs

The article demonstrates why distributed locks alone fail to guarantee idempotency in Spring Boot order APIs, and presents a three-layer solution combining Idempotency-Key with request fingerprinting, Redis SET NX for fast duplicate interception, and a database unique constraint as the ultimate safeguard against duplicate orders even after crashes or Redis failures.