Registry / devops / esm-async-queue

esm-async-queue

library0.2.2jsnpmunverified

ESM-only, dependency-free async queue for Node.js and browsers. Version 0.2.2 (released 2024). Processes n tasks concurrently, starting immediately on push. Includes TypeScript definitions and event subscriptions (idle, taskProcessing, taskProcessed, taskPushed). No dependencies. Lightweight alternative to async.queue or p-limit.

devops

npm install esm-async-queue

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · ESM-ASYNC-QUEUE

esm-async-queue

devopsjavascriptv0.2.2

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

Queue

✓ import { Queue } from 'esm-async-queue'

✗ const Queue = require('esm-async-queue')

Package is ESM-only; CommonJS require() throws ERR_REQUIRE_ESM.

Queue (default import)

✓ import { Queue } from 'esm-async-queue'

✗ import Queue from 'esm-async-queue'

No default export; named import 'Queue' only.

Queue type

✓ import type { Queue } from 'esm-async-queue'

TypeScript users can import the type for type annotations.

Creates a queue with concurrency 2, pushes three async tasks, and subscribes to the 'idle' event.

import { Queue } from 'esm-async-queue'; const delayed = (ms: number) => new Promise(resolve => setTimeout(resolve, ms)); const queue = new Queue({ concurrency: 2 }); queue.push(() => delayed(200).then(() => console.log('task 1 done'))); queue.push(() => delayed(100).then(() => console.log('task 2 done'))); queue.push(() => delayed(300).then(() => console.log('task 3 done'))); queue.subscribe('idle', () => console.log('all tasks complete'));

Debug

Known issues

gotchaQueue length includes all tasks (pending + processing), not just pending.

fix

Use 'tasksProcessing' and 'tasksPending' properties separately to track specific counts.

affects: >=0.0.0

gotchaEvent subscription returns an unsubscribe function, but calling it more than once causes a console.warn.

fix

Unsubscribe only once per subscription; avoid double unsubscribe.

affects: >=0.0.0

gotchaTasks must be functions that return a PromiseLike or be async. Passing a plain Promise directly will not work.

fix

Wrap promises in a function: () => myPromise.

affects: >=0.0.0

Errors

Common errors & fixes

ERR_REQUIRE_ESM

Using require() to import an ESM-only module.

fix

Change to import statement: import { Queue } from 'esm-async-queue'

TypeError: queue.push is not a function

Using default import instead of named import.

fix

Use import { Queue } from 'esm-async-queue' (curly braces).

Upgrade

Version history

0.2.2latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

2 hits · last 30 days

node

Resources

githubhttps://github.com/danielgormly/esm-async-queue ↗

packageesm-async-queue ↗

homepagehttps://github.com/danielgormly/esm-async-queue#readme ↗