Idempotency key ignored

Retries from a mobile client create duplicate payments even though every request includes the same idempotency key. Request logs contain the key, but the resulting payment records cannot be correlated reliably.

Initial failing signalA retried payment creates a second recordExpected behavior: The database receives the request idempotency key · actual behavior: The database options are undefined

Progress

1Reproduce the bugRun checks

2Edit the fixOpen

3Pass checksOpen

4Submit fixOpen

Reproduction Steps

Run npm test.
Compare the first request with a retry carrying the same key.
Trace the key across the request and payment creation boundaries.
Restore idempotent behavior without rejecting new payments.

Focus Mode

Start

src/payment-handler.mjs
tests/payment-handler.test.mjs

Likely area

src/payment-handler.mjs

Repo scale

4 files
Small payment API

Challenge Coach

Hints reveal broad direction first, then narrow toward the suspect path without showing hidden tests or exact solution code.

TopicAPI & Request Flow

DifficultyMedium

Est. time20 min

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workspace

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