#Job logs and flows

Two features people often miss.

#Job logs

In a BullMQ worker, call job.log() to push lines that appear in the dashboard's job detail view:

import { Worker } from 'bullmq';

new Worker('emails', async (job) => {
  await job.log(`Sending to ${job.data.to}`);
  await sendEmail(job.data);
  await job.log('Sent.');
}, { connection });

Open the job in the dashboard, switch to the Logs tab.

Live example: open the demo and drill into a worker-processed job in emails:welcome.

#Job flows

BullMQ supports flows. Parent jobs that wait on child jobs across queues. Build one with FlowProducer:

import { FlowProducer } from 'bullmq';

const flow = new FlowProducer({ connection });

await flow.add({
  name: 'build-report',
  queueName: 'reports',
  children: [
    { name: 'fetch-data', queueName: 'fetch' },
    { name: 'render-pdf', queueName: 'render' },
  ],
});

Bull-board renders the tree on the parent job's detail view. Click through to jump between parents and children.

Live example: open the demo and scroll to reports:nightly for a parent job with children.

Caveat: job.log() is BullMQ-only. Bull has no equivalent.