Callback heaven

callback-heaven.js

function create(callback) {
  setTimeout(function() {
    callback('created')
  }, Math.random() * 1000)
}

function read(value, callback) {
  setTimeout(function() {
    callback(value + ', red')
  }, Math.random() * 1000)
}

function update(value, callback) {
  setTimeout(function() {
    callback(value + ', updated')
  }, Math.random() * 1000)
}

function delete_(value, callback) {
  setTimeout(function() {
    callback(value + ', deleted')
  }, Math.random() * 1000)
}

// Consumers

function createNewFile() {
  create(readDir)
}

function readDir(value) {
  read(value, updateDB)
}

function deleteFiles(value) {
  delete_(value, logResult)
}

function updateDB(value) {
  update(value, deleteFiles)
}

function logResult(value) {
  console.log(value + ', finished')
}

createNewFile()