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Challenges / Orders API charges twice
Run tests1import { Router } from "express";2import { charge } from "../payments.js";3import { db } from "../db.js";45export const ordersRouter = Router();67ordersRouter.post("/", async (req, res) => {8const { cartId, total } = req.body;9const payment = await charge(cartId, total);1011const existing = await db.orders.findByCart(cartId);12if (existing) return res.status(200).json(existing);1314const order = await db.orders.create({ cartId, total, payment });15res.status(201).json(order);16});
- charges once on retry
Why does the retry test see two charges?
The test posts the same cart twice and expects
chargeto run once.In
routes/orders.js, compare line 9 with the duplicate check on line 11. On the second request, which one runs first?
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Tracks
Backend, frontend or both.Practise on the stack your interview uses.
Node.js · Express
Backend
APIs with broken routing, validation, async error handling and data access.
React
Frontend
Apps with stale state, runaway effects, broken forms and rendering bugs.
Node.js · React
Full-stack
Both in one repository, with bugs that cross the API boundary.
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