Replay completed mutations and coalesce concurrent requests within one
middleware instance. Keys include explicit scope, method and full request URL.
Reusing a key means retrying the same input; bodies are not fingerprinted.
This is not durable exactly-once execution: restarts, expiry and thrown
failures may permit another execution. Use database deduplication for that.
Oversized/incomplete responses retain a non-replayable reservation (409).
Capacity exhaustion returns 503 without executing the operation.
Replay completed mutations and coalesce concurrent requests within one middleware instance. Keys include explicit scope, method and full request URL. Reusing a key means retrying the same input; bodies are not fingerprinted. This is not durable exactly-once execution: restarts, expiry and thrown failures may permit another execution. Use database deduplication for that. Oversized/incomplete responses retain a non-replayable reservation (409). Capacity exhaustion returns 503 without executing the operation.