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Backend & API Intermediate 3 possible tests

Idempotency Issues

A card creation form that should be idempotent — submitting it twice with the same data must not create duplicate records. One endpoint is broken, one is protected. Find the difference.

What is this?

An idempotent operation produces the same result no matter how many times it's repeated. In APIs this matters for retries — if a network timeout causes a client to re-submit a form, the server must not create duplicate records. Idempotency tokens are one common solution.

What is hidden here

BugSubmit the form twice with the same name → 2 records created (no deduplication)
CorrectSubmit with the same idempotency token twice → only 1 record created
ResetClear all state between test runs

Create Card Form


Record Count
Cards in State
Suggested Test Inputs
  • Click Create Card (Buggy) twice with the same name and count the results
  • Try the idempotency-protected endpoint — submit the same token twice
  • Click Reset between test runs to clear state