Building a Resilient Checkout in NestJS: Retry, Idempotency, and a System That Tunes Itself
The article discusses the challenges of implementing a resilient checkout system in NestJS, particularly focusing on payment gateway failures. It highlights the importance of retry mechanisms and idempotency to prevent double charges during transactions. The author shares insights from stress tests conducted to measure the system's performance under various failure scenarios.
- ▪The checkout system includes a pipeline with steps for validating inventory, calculating pricing, charging payments, and creating orders.
- ▪Idempotency is achieved by using a unique key per order, ensuring that retries do not result in duplicate charges.
- ▪A circuit breaker is implemented to manage service degradation during high failure rates, allowing the system to respond quickly without overwhelming the service.
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try { if(localStorage) { let currentUser = localStorage.getItem('current_user'); if (currentUser) { currentUser = JSON.parse(currentUser); if (currentUser.id === 1076958) { document.getElementById('article-show-container').classList.add('current-user-is-article-author'); } } } } catch (e) { console.error(e); } Mairon José Cuello Martinez Posted on May 20 Building a Resilient Checkout in NestJS: Retry, Idempotency, and a System That Tunes Itself #architecture #backend #node #systemdesign The problem nobody talks about You have a payment gateway. It fails sometimes. So you add a retry. Now you have a worse problem: a customer clicks "Pay", the request reaches Stripe, the charge goes through, but the response never comes back. Your retry fires. Stripe charges them again.
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