Exponential backoff

README.md

Usage

import Backoff from './Backoff';
import apisauce from 'apisauce';

const backoff = Backoff.create({
  shouldBackoff(response) {
    return response.status === 429;
  }
});

const client = apisauce.create({
  baseURL: 'https://google.com'
});

const response = await backoff.run(() => client.get('/'));

Backoff.js

const create = ({
  shouldBackoff,
  factor = 5,
  maxDelay = 32000,
  maxAttempts = 20
}) => {
  const backoff = attempt => {
    const randomMs = Math.floor(Math.random() * 1000);
    const exponential = Math.pow(factor, attempt) + randomMs;
    const delay = Math.min(exponential, maxDelay);
    return new Promise(resolve => setTimeout(resolve, delay));
  };

  const run = async request => {
    let attempts = 0;

    while (attempts <= maxAttempts) {
      const response = await request();

      if (!shouldBackoff(response)) {
        return response;
      }

      await backoff(++attempts);
    }

    throw new Error("Backoff reached maximum attempts");
  };

  return {
    run
  };
};

export default {
  create
};