export ES6 module after awaiting

Question

I have a module I need to export, but I want to export it after all async operations have finished. Essentially, I need the exported module to be "async ready" at the time I export it

class Store {
   async dummy() {
      await somethingElse()
   }
}

const store = new Store();

// at this point, before exporting it, I want to
await store.dummy()

// but since I am not in a function, I cannot await it
export { store }

Any ideas?

Module-level `await` is not possible for now. Your best bet will be to export the promise. — Bergi, May 09 '18 at 12:48
Hm, interesting question. I wonder in what scenario you would really need to do this. — Hinrich, May 09 '18 at 13:07
This is now possible, see the answers to the [linked question](https://stackoverflow.com/questions/46515764/how-can-i-use-async-await-at-the-top-level). — T.J. Crowder, Oct 04 '22 at 09:43

score 1 · Answer 1 · answered May 09 '18 at 12:56

This is part of the red-blue problem we face in Javascript, and basically there isn't a good solution. Once you've introduced asynchronicity, you're async all the way. If you try to await, any function that awaits will be default be a promise factory. As was suggested your best bet is to return a promise, but without being able to do any kind of thread blocking you're stuck in promise land.

janniks · Answer 2 · 2018-05-09T13:02:46.743

1

Using await on a module scope is not possible at the moment of writing.

Try rewriting your module to export a method that will use the async/await functionality.

There is no option of mixing asynchronous and sequential code. You have to go all in! (As described in TheCog's answer: http://journal.stuffwithstuff.com/2015/02/01/what-color-is-your-function/)

edited May 09 '18 at 13:02

answered May 09 '18 at 12:57

janniks

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score 0 · Answer 3 · answered May 10 '18 at 07:44

I was able to get away with it, but basically due to the use case I had Basically, I have a react application and the module in question is the one that initializes all of my stores and services

So I ended up solving it by awaiting it, when I import it and before passing it to the main react component

const load = async () => {
    const rootEl = document.getElementById('app');
    //below the solution
    **await bootstrap.RootStore.init();**
    routeInit(bootstrap.RootStore.getService('logger'), bootstrap.RootStore.UIStore);
    render(
        <Provider {...bootstrap}>
            <Router history={browserHistory} onUpdate={bootstrap.RootStore.UIStore.trackPage} routes={routes} />
        </Provider>,
        rootEl
    );
}

load();

export ES6 module after awaiting

3 Answers3