Promise loop (can use as a long-running worker) with predicate.

promiseWhile

/**
 * Hat Tip: https://gist.github.com/victorquinn/8030190#gistcomment-1615901
 */
 
'use strict'

var Promise = require('bluebird')
var times = 0

function promiseWhile (predicate, action) {
  function loop () {
    if (!predicate()) {
      return
    } else {
      return Promise.resolve(action()).then(loop)
    }
  }

  return Promise.resolve().then(loop)
}

function isOK () {
  return times < 5
}

function work () {
  return Promise.delay(1500).then(() => {
    times += 1
    console.log('hello there')
  })
}

promiseWhile(isOK, work)