@chriscdn/promise-timeout

This utility wraps a promise or asynchronous function and will reject if the wrapped promise or function doesn't resolve or reject within a specified time limit. If it resolves or rejects within the given time, the utility returns the result.

Keep in mind that a timed-out promise will remain pending and may still resolve or reject in the future. This package only allows you to maintain control over operations that take longer than expected.

Installing

Using npm:

npm install @chriscdn/promise-timeout

Using yarn:

yarn add @chriscdn/promise-timeout

Breaking Changes to v2

The import and interface changed slightly. See below.

Usage

The package provides a promiseTimeout and an asyncTimeout function. The promiseTimeout function is designed for use with a Promise, whereas the asyncTimeout function is intended for an async function (which returns a Promise).

Example - Promises

import { promiseTimeout } from "@chriscdn/promise-timeout";

const pause = (ms: number) => new Promise((resolve) => setTimeout(resolve, ms));

// A promise that resolves after 2 seconds.
const myPromise = new Promise((resolve) => pause(2000).then(resolve));

// This will go into the catch block since the timeout is less than 2 seconds
promiseTimeout(myPromise, { timeout: 1000 })
  .then(() => {
    console.log("myPromise resolved normally");
  })
  .catch((err) => {
    console.log(
      "myPromise rejected, or did not resolve or reject withing 5000ms"
    );
  });

Example - Async Function

import { asyncTimeout } from "@chriscdn/promise-timeout";

try {
  const message = await asyncTimeout(() => pause(1500), {
    timeout: 1000,
    errorMessage: "The request timed out.",
  });
} catch (e) {
  // The request timed out.
  console.log(e.message);
}

Options

The promiseTimeout and asyncTimeout functions accept an Options object, with the following defaults:

const options = {
  timeout: 30000, // timeout, in milliseconds
  onTimeout: () => {}, // callback if a timeout occurs, called before promise is rejected
  errorMessage: "The promise timed out.", // The time out exception. Used when constructing the error object.
};

License

MIT