drone-simple.js

var Drone = require('worker-drone')
  , queue = [ { val : 1 }, { val : 2 }, { val : 0 }, { val : 2 }, { val : 4 } ]
  , results = [ ]

var worker = new Drone({
    work: function (data, callback) {
      data.val += 5
      callback(null, data)
    }
  , poll: 1000
  , concurrency: 15
})

worker
  .on('pop', function (callback) { 
    // worker drone is requesting a new thing
    if (queue.length) {
      callback(null, queue.pop())
    }
    // Note:
    // the queue could easily be persisted in redis 
    // or another location. e.g.
    // redis.lpop('worker-set', callback)
  })
  .on('error', function (error) { 
    // work function callback contained an error
    console.error(error)
  })
  .on('push', function (item) { 
    // worker drone finished with an item
    results.push(item)
  })
  .start()

//
// push a value onto the worker queue directly
worker.push({ val : 0 })

//
// push new items onto the queue that our worker will look at
setInterval(function () {
  queue.push({ val : Math.random() })
  console.log(results)
}, 1500)