Promise timeout

promise-timeout.js

// https://github.com/github/fetch/issues/175#issuecomment-216791333
function timeoutPromise(ms, promise) {
  return new Promise((resolve, reject) => {
    const timeoutId = setTimeout(() => {
      reject(new Error('promise timeout'));
    }, ms);
    promise.then(
      res => {
        clearTimeout(timeoutId);
        resolve(res);
      },
      err => {
        clearTimeout(timeoutId);
        reject(err);
      }
    );
  });
}