Quick Start
This is a basic guide to get your first queue working.
Install using npm:
$ npm install bullmq
Install using yarn:
$ yarn add bullmq
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();
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';
const worker = new Worker(queueName, async job => {
// Will print { foo: 'bar'} for the first job
// and { qux: 'baz' } for the second.
console.log(job.data);
});
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}`);
});
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();
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 ${failedReason}`);
});
You may also access the timestamp of the event, which looks like "1580456039332-0".
import { QueueEvents } from 'bullmq';
const queueEvents = new QueueEvents();
queueEvents.on('progress', ({ jobId, data }, timestamp) => {
console.log(`${jobId} reported progress ${data} at ${timestamp}`);
});
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.Last modified 9mo ago