@5zx/request-dedup

Request de-duplication utilities with idempotency key support.

Install

npm install @5zx/request-dedup

Usage (Axios example)

import {
  buildIdempotencyKey,
  isDedupCandidate,
  tryAcquireKey,
  releaseRequest,
  markCooldown,
  resolveIdempotencyHeader,
  resolveWindowMs,
  DuplicateRequestError,
} from '@5zx/request-dedup';

axios.interceptors.request.use((config) => {
  const options = config.requestOptions || {};
  if (isDedupCandidate(config, options)) {
    const key = buildIdempotencyKey(config, options);
    if (!tryAcquireKey(key)) {
      throw new DuplicateRequestError();
    }
    const headerName = resolveIdempotencyHeader(options);
    const windowMs = resolveWindowMs(options);
    config.__dedupKey = key;
    config.__dedupWindowMs = windowMs;
    config.headers = config.headers || {};
    config.headers[headerName] = key;
  }
  return config;
});

axios.interceptors.response.use(
  (response) => {
    releaseRequest(response.config.__dedupKey);
    markCooldown(response.config.__dedupKey, response.config.__dedupWindowMs);
    return response;
  },
  (error) => {
    releaseRequest(error?.config?.__dedupKey);
    markCooldown(error?.config?.__dedupKey, error?.config?.__dedupWindowMs);
    return Promise.reject(error);
  },
);

Options

• repeatRequest.enabled: enable/disable de-dup.
• repeatRequest.windowMs: cooldown window in ms.
• idempotencyKey: override key generation.
• idempotencyHeader: override header name.