events.addAbortListener

History

events.addAbortListener(signal, listener): Disposable

Attributes

signal:AbortSignal

listener:Function | EventListener

Returns:Disposable

A Disposable that removes the abort listener.

Listens once to the abort event on the provided signal.

Listening to the abort event on abort signals is unsafe and may lead to resource leaks since another third party with the signal can call e.stopImmediatePropagation(). Unfortunately Node.js cannot change this since it would violate the web standard. Additionally, the original API makes it easy to forget to remove listeners.

This API allows safely using AbortSignals in Node.js APIs by solving these two issues by listening to the event such that stopImmediatePropagation does not prevent the listener from running.

Returns a disposable so that it may be unsubscribed from more easily.

const { addAbortListener } = require('node:events');

function example(signal) {
  signal.addEventListener('abort', (e) => e.stopImmediatePropagation());
  // addAbortListener() returns a disposable, so the `using` keyword ensures
  // the abort listener is automatically removed when this scope exits.
  using _ = addAbortListener(signal, (e) => {
    // Do something when signal is aborted.
  });
}

JavaScript

import { addAbortListener } from 'node:events';

function example(signal) {
  signal.addEventListener('abort', (e) => e.stopImmediatePropagation());
  // addAbortListener() returns a disposable, so the `using` keyword ensures
  // the abort listener is automatically removed when this scope exits.
  using _ = addAbortListener(signal, (e) => {
    // Do something when signal is aborted.
  });
}

JavaScript