API Design · Senior · Question 12 of 75

How long should a server keep idempotency keys?

1Forever
✓Correct answer: Long enough to cover realistic client retry windows (e.g. 24 hours), documented, then expire them
3One second

Explanation

Expiring keys bounds storage. Clients must not reuse keys for different operations.

Further reading

Stripe: Idempotent requests ↗

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