Can I return an async value (a Promise) from a Meteor helper?

I’m working on some code that may allow helper methods to return promises, and reactively update. It’s different from simple:reactive-method in a way, in that it works with any promise type, and you invoke it by wrapping a promise-returning helper in PromiseHelper as shown:

  promiseHelper: PromiseHelper(function(v) {
    var s;
    s = v + ":" + textDep.get();
    return new Promise(function(resolve) {
      setTimeout(function() {
        resolve(s + ':promise');
      }, 1000 + Math.random() * 2000);

Before I do any more work on this though - is it valuable to anyone? Is it redundant to something that already exists ? Here’s the code that makes the above work: - Code-specific comments welcome in the gist.


FYI Here’s an update that works!

Hi @deanius I see that you’ve deprecated your package in favour of the package from okgrow. Is that package also still needed now that we have

Hi @dcworldwide!

The MDG package does very little, and it is used by okgrow:promise, which delivers many helpers on top of it. FYI I work for OK Grow now, so that’s why the package is housed under them now :smile:

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Any chance you could give some insight into how the okgrow package actually addresses this issue? Trying to learn Meteor and Promises right now and have been working with okgrow:promise but haven’t had much success. I can use the promise methods to chain all sorts of things together and get the right results, but no matter I try, I can’t get them to actually bubble up to the template and render. Is there something else I need to do when using the Meteor.promise -> .then -> .then pattern to get the data out of the fulfilled promise?

@cafreeman - There are examples on the docs site, for example, the first one: I’d explain more but I think the answer you are looking for is right there in the docs (see ReactivePromise wrapping the helper function?)