@philiprehberger/async-queue

Priority queue for async tasks with concurrency control

Installation

npm install @philiprehberger/async-queue

Usage

import { createQueue } from '@philiprehberger/async-queue';

const queue = createQueue({ concurrency: 2 });

queue.add(() => fetch('/api/one'));
queue.add(() => fetch('/api/two'));
queue.add(() => fetch('/api/urgent'), { priority: 10 });

await queue.onIdle();
console.log('All tasks complete');

Pause and resume

queue.pause();
queue.add(() => fetch('/api/deferred'));
queue.resume(); // queued tasks start executing

Abort signal

const controller = new AbortController();
const queue = createQueue({ concurrency: 3, signal: controller.signal });

queue.add(() => longRunningTask());
controller.abort(); // clears pending tasks

API

| Export | Description | | --- | --- | | createQueue(options?) | Create a new async queue instance | | QueueOptions.concurrency | Max concurrent tasks (default: Infinity) | | QueueOptions.signal | AbortSignal to cancel the queue | | queue.add(fn, options?) | Add a task; returns a promise for its result | | AddOptions.priority | Higher number = higher priority (default: 0) | | queue.pause() | Pause task execution | | queue.resume() | Resume task execution | | queue.clear() | Reject and remove all pending tasks | | queue.onIdle() | Promise that resolves when queue is idle | | queue.onEmpty() | Promise that resolves when no pending tasks remain | | queue.size | Number of pending tasks | | queue.running | Number of currently running tasks | | queue.isPaused | Whether the queue is paused |

Development

npm install
npm run build
npm test

License

MIT