Quick Start

Install

Install using npm:

$ npm install bullmq

Install using yarn:

$ yarn add bullmq

INFO

BullMQ is written in TypeScript, and although it can be used in vanilla JavaScript, all examples in this guide will be written in TypeScript.

Import into your project and add some jobs:

import { Queue } from 'bullmq';

const myQueue = new Queue('foo');

async function addJobs() {
  await myQueue.add('myJobName', { foo: 'bar' });
  await myQueue.add('myJobName', { qux: 'baz' });
}

await addJobs();

DANGER

You need to have a Redis service running in your local computer to run these examples successfully. You can read more about Redis connections here.

Jobs are added to the queue and can be processed at any time, with at least one Node.js process running a worker:

import { Worker } from 'bullmq';
import IORedis from 'ioredis';

const connection = new IORedis({ maxRetriesPerRequest: null });

const worker = new Worker(
  'foo',
  async job => {
    // Will print { foo: 'bar'} for the first job
    // and { qux: 'baz' } for the second.
    console.log(job.data);
  },
  { connection },
);

INFO

You can have as many worker processes as you want, BullMQ will distribute the jobs across your workers in a round robin fashion.

You can listen to completed (or failed) jobs by attaching listeners to the workers:

worker.on('completed', job => {
  console.log(`${job.id} has completed!`);
});

worker.on('failed', (job, err) => {
  console.log(`${job.id} has failed with ${err.message}`);
});

INFO

There are many other events available, check the Guide or the API reference for more information.

Sometimes you need to listen to all the workers events in a given place, for this you need to use a special class QueueEvents:

import { QueueEvents } from 'bullmq';

const queueEvents = new QueueEvents('my-queue-name');

queueEvents.on('waiting', ({ jobId }) => {
  console.log(`A job with ID ${jobId} is waiting`);
});

queueEvents.on('active', ({ jobId, prev }) => {
  console.log(`Job ${jobId} is now active; previous status was ${prev}`);
});

queueEvents.on('completed', ({ jobId, returnvalue }) => {
  console.log(`${jobId} has completed and returned ${returnvalue}`);
});

queueEvents.on('failed', ({ jobId, failedReason }) => {
  console.log(`${jobId} has failed with reason ${failedReason}`);
});

You may also access the timestamp of the event, which looks like "1580456039332-0".

import { QueueEvents } from 'bullmq';

const queueEvents = new QueueEvents('my-queue-name');

queueEvents.on('progress', ({ jobId, data }, timestamp) => {
  console.log(`${jobId} reported progress ${data} at ${timestamp}`);
});

DANGER

For performance reasons, the events emitted by a QueueEvents instance do not contain the Job instance, only the jobId. Use the Job.fromId method if you need the Job instance.