Proof: one job per worker run

avoidLeaksWithOneJobPerWorkerRun.js

const os = require('os');

var kue = require('kue');

var queue = kue.createQueue({
  redis: process.env.REDIS_URL
});

var JOB_NAME = 'crawl';

var doNotCorruptGlobalNamespace = 1;

queue.process(JOB_NAME, function(job, ctx, done){
  console.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'inside queue.process("'+JOB_NAME+'") for job id:', job.id);
  job.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'inside queue.process("'+JOB_NAME+'") for job id:', job.id);
  doSomething(job, ctx, done);
});

// WARN: if we forget a variable in the signature and NODE crashes,
//       the container does not shutdown in 1 out of a 1000 times
function doSomething(job, ctx, done) {
  var payload = job.data;
  console.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'inside doSomething()');
  job.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'inside doSomething()');
  setTimeout(function() { // pretend to work and finish after few seconds
    console.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'doNotCorruptGlobalNamespace', ++doNotCorruptGlobalNamespace );
    job.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'doNotCorruptGlobalNamespace', ++doNotCorruptGlobalNamespace );

    console.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'successfully ran the job:', job.id);
    //console.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'payload', payload);
    done();
  }, 5000);
}

// Shut down after processing only one job
setTimeout( function () {
  console.log( os.hostname(), process.pid, (new Date()).toLocaleString(), '[ Shutting down when all jobs finish... ]' );
  queue.shutdown( function ( err ) {
    console.log( os.hostname(), process.pid, (new Date()).toLocaleString(), '[ All jobs finished. Kue is shut down. ]' );
    process.exit( 0 );
  } )
}, 1000 );

showThatBadCodeCanLeakDataAcrossJobs.js

const os = require('os');

var kue = require('kue');

var queue = kue.createQueue({
  redis: process.env.REDIS_URL
});

var JOB_NAME = 'crawl';

var doNotCorruptGlobalNamespace = 1;

queue.process(JOB_NAME, function(job, ctx, done){
  console.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'inside queue.process("'+JOB_NAME+'") for job id:', job.id);
  job.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'inside queue.process("'+JOB_NAME+'") for job id:', job.id);
  doSomething(job, ctx, done);
});

// WARN: if we forget a variable in the signature and NODE crashes,
//       the container does not shutdown in 1 out of a 1000 times
function doSomething(job, ctx, done) {
  var payload = job.data;
  console.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'inside doSomething()');
  job.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'inside doSomething()');
  setTimeout(function() { // pretend to work and finish after few seconds
    console.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'doNotCorruptGlobalNamespace', ++doNotCorruptGlobalNamespace );
    job.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'doNotCorruptGlobalNamespace', ++doNotCorruptGlobalNamespace );

    console.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'successfully ran the job:', job.id);
    //console.log( os.hostname(), process.pid, (new Date()).toLocaleString(), 'payload', payload);
    done();
  }, 5000);
}