Deployment with Docker

index.js

index.js is a single-file app that either sends a timestamp every 1.5 seconds to the queue or reads from the queue depending on the invocation argument. The queue location is defined by the QUEUE_HOST environment variable:

'use strict'const Queue = require('bull');const veryImportantThingsQueue = new Queue('very_important_things',                                           { redis: { port: 6379,                                                      host: process.env.QUEUE_HOST }});// Prints any message data receivedclass Receiver {    constructor () {        console.info('Registering listener...');        veryImportantThingsQueue.process(job => {            console.info('Got a message from the queue with data:', job.data);            return Promise.resolve({});        });    }}// Sends the date every 1.5 secondsclass Sender {    constructor () {        function sendMessage() { const ...