Async Wait

This is small JavaScript utility that waits for many async operations to finish. This is very similar to something like async.map or Promise.all, but with a much looser API.

Install

Download the latest version from our release page and use via a script tag. The variable asyncWait will be attached to window.

<script type="text/javascript" src="asyncwait.js"></script>

If using Browserify or Node.js, you can install via NPM and use via require("asyncwait").

$ npm install asyncwait

Usage

Call asyncWait() with an onEmpty callback. This function will be called when the wait queue is completely drained. This will return a wait function which can be wrapped around any async callback.

var wait = asyncWait(function() {
    console.log("done");
});

setTimeout(wait(function() {
    console.log("my timeout");
}), 100);

It also plays really nice with ES6 Promises:

var wait = asyncWait(function() {
    console.log("done");
});

// called outside so it is registered immediately
var done = wait();

myAsyncTask().then(function() {
    console.log("success");
    done();
}, done);