RabbitMQ graceful shutdown in NodeJS

rabbit-graceful-shutdown.js

const amqp = require('amqplib');
const uuid = require('uuid')

const CONSUMER_TAG = uuid.v4();
const QUEUE_NAME = 'my_queue'

async function main() {
  const conn = await amqp.connect('amqp://guest:guest@localhost:5672/%2F');
  const channel = await conn.createChannel();
  await channel.assertQueue(QUEUE_NAME);

  let messagesBeingProcessed = 0;

  console.log('Ready to consume messages...');
  channel.consume(QUEUE_NAME, async (rawMsg) => {
    messagesBeingProcessed++;

    console.log('Sleeping...');
    await sleep(20000);

    console.log('Acking message...');
    channel.ack(rawMsg);

    console.log('Done!');
    messagesBeingProcessed--;
  }, { consumerTag: CONSUMER_TAG });

  process.on('SIGTERM', async () => {
    await channel.cancel(CONSUMER_TAG);

    while(true) {
      if (messagesBeingProcessed === 0) break;
      await sleep(100);
    }

    console.log('Closing channel...');
    await channel.close();

    console.log('Closing connection...');
    await conn.close();

    console.log('Ready to shutdown!')
  });
}

function sleep(timeout) {
  return new Promise(resolve => setTimeout(resolve, timeout));
}

main();