Code reviewHardcr-g089

Subject IdempotencyLevel Senior–Staff~30 minCommon in Networking & APIs interviewsIndustries Software development

Question

Review this Java idempotent-order endpoint.

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Code to reviewjava

1@PostMapping("/orders")2public Order create(@RequestBody OrderReq req,3                    @RequestHeader("Idempotency-Key") String key) {4    Order existing = repo.findByIdempotencyKey(key);5    if (existing != null) {6        return existing;7    }8    Order order = new Order(req);9    order.setIdempotencyKey(key);10    repo.save(order);11    paymentService.charge(order);12    return order;13}

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