promise_with_timeout.js

function wait(signal, ms) {
  return new Promise((res, rej) => {
    const timeOut = setTimeout(() => {
      console.log("I was called");
      res("ok");
    }, ms);

    signal.catch(err => {
      rej(err);
      clearTimeout(timeOut);
    });
  });
}

function createTimedSignal(ms) {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      reject(new Error(`Time out after ${ms}ms`));
    }, ms);
  });
}

const signal = createTimedSignal(500);

const promise = wait(signal, 1000);
promise.then(res => console.log(res)).catch(err => console.log(err));