doc.cheap

idempotency_conflict (409)

The idempotency key was used before, with a different request.

Cause

A key is matched against a fingerprint of the body it was first used with. Two different bodies under one key is the one case a key cannot arbitrate. Returning the first result would answer a question nobody asked. Running the second would charge twice for a key that promised it would not.

The message

Idempotency-Key 8f3c2a1b-5d4e-4f60-9a7b-3c2d1e0f9a8b was already used with a different body.

The fix

Send the new body under a new key. A key belongs to one request, not to one retry loop.

event_id

event_id is always null on this code. It is a refusal the caller is meant to handle, so nothing is recorded as a failure to look at. The service answers and writes one log line.

The whole catalogue, grouped by what a caller does with it, is on errors.

The response

{
  "error": {
    "code": "idempotency_conflict",
    "message": "Idempotency-Key 8f3c2a1b-5d4e-4f60-9a7b-3c2d1e0f9a8b was already used with a different body.",
    "docs_url": "https://doc.cheap/docs/errors/idempotency_conflict",
    "request_id": "req_9e6b1f7c-2d4a-4b83-9c51-7f0ad3e8b642",
    "event_id": null
  }
}