API Design · Middle · Question 18 of 75

How does an idempotency key work on the server?

✓Correct answer: The server stores the key with the request fingerprint and the response; repeats with the same key return the stored response instead of doing the work again
2The key encrypts the request
3The server rejects all requests that have a key

Explanation

Keys expire after some time. If the same key comes with a different body, return an error, since it's likely a client bug.

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