Asynchronous https firebase functions

Question

Should HTTPS functions return asynchronous promises like realtime functions have to? We haven't been returning in HTTPS functions (just using res.status.send etc), and it looks like firebase/function-samples aren't either. But the documentation is slightly ambiguous https://firebase.google.com/docs/functions/terminate-functions .

Answer 1

This works now in the latest Firebase:

exports.asyncFunction = functions.https.onRequest(async (request, response) => {
    const result = await someAsyncFunction();
    response.send(result);
});

Answer 2

HTTP functions currently do not respect returned promises - they require a sent result in order to terminate normally. If an HTTP function doesn't send a result, it will time out.

All other types of functions require a returned promise in order to wait for asynchronous work to fully complete.

If you don't have any async work to wait for, you can just return immediately.

These are the three cases outlined in the docs.