Resolve a promise once all internal concurrent promises have resolved or rejected

Question

I am looking for something similar to Promise.all that will continue to resolve promises concurrently even in the event that one or more of the promises reject

Answer 1

I have succeeded in using Promise.all together with only ever resolving the fetchRequest promises

That's basically the way to go. ES6 does not have a helper function like allSettled (Q) or settle (Bluebird 2.x) for this case, so we will need to use Promise.all similar to like you did. Bluebird even has a dedicated .reflect() utility for this.

You would however not resolve them with undefined in the case of a rejection, but rather with some useful value that allows to identify the errors.

function promiseRequests(requests) {
  return Promise.all(requests.map(request => {
    return fetch(request).then(res => {
      return {value:res};
    }, err => {
      return {reason:err};
    });
  }));
}