p-timeout
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6.1.2 • Public • Published

p-timeout

Timeout a promise after a specified amount of time

Install

npm install p-timeout

Usage

import {setTimeout} from 'node:timers/promises';
import pTimeout from 'p-timeout';

const delayedPromise = setTimeout(200);

await pTimeout(delayedPromise, {
	milliseconds: 50,
});
//=> [TimeoutError: Promise timed out after 50 milliseconds]

API

pTimeout(input, options)

Returns a decorated input that times out after milliseconds time. It has a .clear() method that clears the timeout.

If you pass in a cancelable promise, specifically a promise with a .cancel() method, that method will be called when the pTimeout promise times out.

input

Type: Promise

Promise to decorate.

options

Type: object

milliseconds

Type: number

Milliseconds before timing out.

Passing Infinity will cause it to never time out.

message

Type: string | Error | false
Default: 'Promise timed out after 50 milliseconds'

Specify a custom error message or error to throw when it times out:

  • message: 'too slow' will throw TimeoutError('too slow')
  • message: new MyCustomError('it’s over 9000') will throw the same error instance
  • message: false will make the promise resolve with undefined instead of rejecting

If you do a custom error, it's recommended to sub-class TimeoutError:

import {TimeoutError} from 'p-timeout';

class MyCustomError extends TimeoutError {
	name = "MyCustomError";
}
fallback

Type: Function

Do something other than rejecting with an error on timeout.

You could for example retry:

import {setTimeout} from 'node:timers/promises';
import pTimeout from 'p-timeout';

const delayedPromise = () => setTimeout(200);

await pTimeout(delayedPromise(), {
	milliseconds: 50,
	fallback: () => {
		return pTimeout(delayedPromise(), {milliseconds: 300});
	},
});
customTimers

Type: object with function properties setTimeout and clearTimeout

Custom implementations for the setTimeout and clearTimeout functions.

Useful for testing purposes, in particular to work around sinon.useFakeTimers().

Example:

import {setTimeout} from 'node:timers/promises';
import pTimeout from 'p-timeout';

const originalSetTimeout = setTimeout;
const originalClearTimeout = clearTimeout;

sinon.useFakeTimers();

// Use `pTimeout` without being affected by `sinon.useFakeTimers()`:
await pTimeout(doSomething(), {
	milliseconds: 2000,
	customTimers: {
		setTimeout: originalSetTimeout,
		clearTimeout: originalClearTimeout
	}
});

signal

Type: AbortSignal

You can abort the promise using AbortController.

Requires Node.js 16 or later.

import pTimeout from 'p-timeout';
import delay from 'delay';

const delayedPromise = delay(3000);

const abortController = new AbortController();

setTimeout(() => {
	abortController.abort();
}, 100);

await pTimeout(delayedPromise, {
	milliseconds: 2000,
	signal: abortController.signal
});

TimeoutError

Exposed for instance checking and sub-classing.

Related

  • delay - Delay a promise a specified amount of time
  • p-min-delay - Delay a promise a minimum amount of time
  • p-retry - Retry a promise-returning function
  • More…

Package Sidebar

Install

npm i p-timeout

Weekly Downloads

12,044,158

Version

6.1.2

License

MIT

Unpacked Size

12 kB

Total Files

5

Last publish

Collaborators

  • sindresorhus