min-retry

No-nonsense retrier for fetch

Usage no npm install needed!

<script type="module">
  import minRetry from 'https://cdn.skypack.dev/min-retry';
</script>

README

min-retry

No-nonsense retrier for fetch or any function returning a Response.

import fetch from 'node-fetch';
import retry from 'min-retry';

// retry(max, fetch) and retry(max)(fetch) are equivalent
const safeFetch = retry(3, fetch);
const firstUser = await safeFetch('/users/1', { method: 'GET' });

min-retry retries up to max attempts only if fetch:

  • returns a Response with status 429 or 500–599
  • throws a FetchError or AbortError

If Response includes a RateLimit-Reset header, min-retry waits delta-seconds or until IMF-fixdate to retry.

If retries exceed max, then the original response or thrown error is passed along. This keeps min-retry extremely transparent and composable with other handlers:

import fetch from 'node-fetch';
import retry from 'min-retry';

const raise = err => { throw err };
const rejectIfNotOkay = res => res.ok ? res : raise(new Error(res.statusText));

const obnoxiousFetch = retry(3, fetch);

// Let's say we've used up our rate limit on hollywood.example
const fetchElvisForMyBirthdayParty = () => obnoxiousFetch(`https://hollywood.example/stars/elvis_presley/schedule`, { method: 'POST' });

const birthdayParty = await fetchElvisForMyBirthdayParty();
// retry gives up after 4 calls and returns 429 response

const birthdayParty = await fetchElvisForMyBirthdayParty()
  .then(rejectIfNotOkay)
  .catch(scheduleLocalArtist('bob-with-a-banjo'));
// retry gives up after 4 calls and passes 429 response to rejectIfNotOkay,
// which rejects with an error so we know to schedule a local artist instead

CommonJS

const retry = require('min-retry');