a queue instance exposes two methods:
- push: push a task (a function that returns a promise). Push returns a promise that resolves/rejects when the task completes
- finish: resolves when the queue is empty
const co = require('co').wrap
const createQueue = require('./')
const q = createQueue()
const play = co(function* () {
q.push(() => promiseTimeout(100))
q.push(() => promiseTimeout(50))
q.push(() => promiseTimeout(10))
// wait for currently queued and/or running tasks finish
q.finish().then(() => {
console.log(`3 down, ${q.length} togo`)
})
q.push(() => promiseTimeout(1))
.then(() => console.log('here comes number 4!'))
})
play()
// "waited 100ms"
// "waited 50ms"
// "waited 10ms"
// "3 down, 1 togo"
// "waited 1ms"
// "here comes number 4!"
function promiseTimeout (millis) {
return new Promise(resolve => {
setTimeout(() => {
console.log(`waited ${millis}ms`)
resolve()
}, millis)
})
}