Idempotency

The Idempotency middleware ensures that multiple identical requests do not result in different outcomes. It works by caching the response of the first request associated with a specific idempotency key and returning the cached response for subsequent requests.

Usage

import { Idempotency } from 'shokupan';

app.post('/payments',
    Idempotency({
        header: 'Idempotency-Key',
        ttl: 86400000 // 24 hours
    }),
    async (ctx) => {
        // ... process payment
        return { status: 'charged' };
    }
);

How it works

1. Client sends a request with an Idempotency-Key header.
2. If the key has been seen before, the server returns the saved response (status, headers, body) without executing the handler again.
3. If the key is new, the handler executes, and the resulting response is saved.

Configuration

Option	Type	Default	Description
header	string	'Idempotency-Key'	The request header to look for the key.
ttl	number	86400000 (24h)	Time to live for the cached response (ms).