Retry function in TypeScript

retry.ts

type Options = {
  maxRetries?: number; // Maximum amount of retries before raising the error (default: 3)
  silent?: boolean; // Minimize the error as warning when retrying the function (default: true)
  wait?: number; // Wait time before each retry in milliseconds (default: 500ms)
  exponentialBackoff?: boolean; // Wait longer every time we retry (default: false)
  randomize?: boolean; // Wait a random amount of time before retrying, maximum double of the given time (default: null)
};

const waitMs = (ms: number) => new Promise(resolve => setTimeout(resolve, ms));
const getRandomInt = (max: number) => Math.floor(Math.random() * max);

const retry = async (fn, opts?: Options, i: number = 1) => {
  const maxRetries = opts?.maxRetries ?? 3;
  const silent = opts?.silent ?? true;
  const wait = opts?.wait ?? 500;
  const exponentialBackoff = opts?.exponentialBackoff ?? false;
  const randomize = opts?.randomize ?? false;

  try {
    // await is important here
    return await fn();
  } catch (error) {
    if (i > maxRetries) {
      throw error;
    }

    console.warn(
      `(${i}/${maxRetries}) Retrying function "${fn.name}" due to the following error`,
    );
    if (!silent) {
      console.warn(error.stack);
    }

    if (wait) {
      await waitMs(
        exponentialBackoff
          ? wait * i
          : randomize
            ? wait / 2 + getRandomInt(wait)
            : wait,
      );
    }

    return await retry(fn, opts, i + 1);
  }
};

export default retry;