Allow for promise events (javascript)

[ghost]

BEFORE SUBMITTING AN ISSUE CHECK THE FOLLOWING:

• [X] I checked existing issues.
• [X] This is not a support question (which can be answered on Slack).
• [X] This issue is for Lambda (not the Web Client, API, or Bots)

FEATURE REQUEST

- Describe the feature you would like to see Would be neat to support promises so we can use async logic in our events. - Why you need it See comments below - How it should work Something like this:

 exports.handler = (event, context, callback) => {
     // This is used to know how much time you have left for your code
     const time_left = context.getRemainingTimeInMillis;

-    callback(null, handleEvent(event, time_left));

+    Promise.resolve(handleEvent(event, time_left)).then(result =>
+        callback(null, result));

 };

[dehli]

What are you thinking would be your use case for async logic? Also in regards to testing, it's kinda tough right now (but we're going to improve how that works).

[ghost]

Some thoughts:

• Most libraries written for Node.js are done so in an async manner.
  • The core libraries are pretty good about providing Sync alternatives, but on npm it's the wild west.
• I'd imagine that the current Lambda execution only has one CPU, but it would be neat to use clusters / multiple cores in the future to squeeze the resources in the 2-3 seconds given per turn.
• It would also be nice for organizing things "on the side" along with your main goal. e.g. keeping track of board state.
  • You can cancel these async "optional" functions if they're taking too long to complete.
  • Can have "first" / data races if you want.

I suppose... JavaScript at heart is async, and restricting it to sync doesn't feel free.

[dehli]

Totally agree! We're going to most likely pass a callback function to your bot. Will update this issue once we add it!