promise.timeout

add timeout support for async function

Install

$ npm i -S promise.timeout

Note

this is target ES5 environment.

API

var ptimeout = require('promise.timeout')

ptimeout(fn, timeout, cancel)

• fn the async function
• timeout in ms
• cancel Boolean, whether support onCancel

var ptimeout = require('promise.timeout')

// a function will cost 20ms
function test() {
  return new Promise(function(resolve, reject) {
    setTimeout(function() {
      resolve(20)
    }, 20)
  })
}

var test10 = ptimeout(test, 10)
var test50 = ptimeout(test, 50)

// 10 timeout
try {
  await test10()
} catch (e) {
  e.should.be.ok()
  e.should.be.instanceof(ptimeout.TimeoutError)
  e.message.should.match(/timeout/)
  e.timeout.should.equal(10)
}

// 50 ok
var _50 = await test50()
_50.should.be.ok()
_50.should.equal(20)

onCancel

1. pass cancel = true to ptimeout(fn, ms, cancel)
2. use onCancel para to register clean callback

var ptimeout = require('promise.timeout')

// a function will cost 20ms
function test(onCancel) {
  return new Promise(function(resolve, reject) {
    var timer = setTimeout(function() {
      resolve(20)
    }, 20)

    // custom clean
    onCancel &&
      onCancel(() => {
        clearTimeout(timer)
      })
  })
}

var test10 = ptimeout(test, 10, true) // enable cancel
try {
  await test10()
} catch (e) {
  e.should.ok()
}

FAQ

Q: Why onCancel

A: Think onCancel like the AbortController

with AbortController you need to

function normalFn(a, r, g, s, controller: AbortController) {
  controller.signal.addEventListener('abort', () => {
    // cancel operations that starts in `normalFn` body
  })
}

• and ptimeout will call the controller.abort() if any timeout exceeds
• and with onCancel, you provide a cancel operation to ptimeout, ptimeout will call that

That's the same, and I don't want to depend on an extra package abort-controller

See Also

• promise.timeout
• promise.retry
• promise.map
• promise.ify
• promise.cb
• promise.obj
• promise.sleep

Changelog

CHANGELOG.md

License

the MIT License http://magicdawn.mit-license.org