vitalets / await-timeout Goto Github PK

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Wouldn't it be better to have:

const timer = Timeout.set(1000); // set the timer
Timeout.clear(timer); // clear the timer

?

Hello!

I've found some unobvious behavior of await-timeout during its inclusion in our project. And want to discuss them with you and community.

So the first my example is:

var awaitTimeout = require("await-timeout");
var timer = new awaitTimeout();

timer.set(5000).then(() => console.log('TIMER'));
setTimeout(() => {
    timer.set(13000);
}, 2000);

This block of code will log TIMER after 5 sec. But at first I thought that it logs TIMER after 15 (2 + 13) sec. because second timer.set(13000) call postpones timer. But in result this second call doesn't influence.

Next example:

var awaitTimeout = require("await-timeout");

var timer = new awaitTimeout();

timer.set(5000).then(() => console.log('TIMER1'));
setTimeout(() => {
    timer.set(5000).then(() => console.log('TIMER2'));
    timer.clear();
}, 2000);

It will log TIMER1, but TIMER2 won't never be logged.

If I understood it correct setting timer is available only once until timer clearing.
Maybe timer has to throw an error in that case then.
And I think it would be great to clarify this cases in Readme.
What do you think?

It runs the test() function start to end, even though it times out. How do I make it abort the function that timed out? Similar to what Bluebird does with the {cancellation: true} feature, but using async/await.

// const Promise = require('bluebird');
// Promise.config({cancellation: true});

const Timeout = require('await-timeout');
const delay = ms => new Promise(_ => setTimeout(_, ms))

 
async function test() {
  console.log('start')
  await delay(2000)
  console.log('end')
}

async function run() {
  const timer = new Timeout();
  try {
    await Promise.race([
      test(),
      timer.set(1200, 'Timeout!')
    ]);
  } catch (e) {
    console.log(e);
  } finally {
    timer.clear();
  }
}

run();

It would also be nice to consider supporting AbortController which would allow the API to be web compatible (cancelling a timer and a fetch at the same time for instance):

const controller = new AbortController()
const timer = Timeout.set(1000, { signal: controller.signal });
signal.abort();

From #3 (comment)

Hello, I have a small quesiton about this code:

import Timeout from 'await-timeout';

const timer = new Timeout();
try {
  await Promise.race([
    fetch('https://example.com'),
    timer.set(1000, 'Timeout!')
  ]);
} finally {
  timer.clear();
}

Without a timer cleanup you may get unexpected effects in you code - as all promises in Promise.race are get fulfille

Why the timer need to be cleanup? race() only accept the first settled promise.