Code reviewHardcr-g494

Subject IdempotencyLevel Senior–Staff~20 minCommon in Networking & APIs interviewsIndustries Software development, Technology

Question

Review this Java payment endpoint. Clients send an `Idempotency-Key` header to make charge creation safe to retry.

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Code to reviewjava

1public ChargeResult createCharge(String idempotencyKey, ChargeRequest req) {2    Optional<ChargeResult> existing = idemRepo.findByKey(idempotencyKey);3    if (existing.isPresent()) {4        return existing.get();5    }6    ChargeResult result = processor.charge(req);7    idemRepo.save(idempotencyKey, result);8    return result;9}

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