A stupidly simple nodejs + socket.io pub/sub for sending asynchronous notifications from your server to the user.

It's not production-grade, but may be useful for prototypes, demos etc. I've used it as a mock e-mail and text message backend.

1. The client makes a random cookie named TellBrowserKey and subs to a channel with that name.
2. The cookie gets sent with subsequent requests.
3. The server can store the cookie and POST to it to notify the user after a background operation completes.

The primary limitation is that if the user happens to be in the middle of a page load while the notification is fired then the notification is lost. Fortunately single-page apps don't suffer from this problem as much. A better implementation might store the messages for a few minutes or until the user has explicitly acknowledged them.

1. Copy config.example.json to config.json and edit if necessary.
2. Run npm install and bower install to download dependencies.
3. Run grunt to build.
4. Start with node app.js.

Currently the app can only be run as a single instance.

Include the following scripts.

<script src="http://localhost:4000/socket.io/socket.io.js"></script>
<script src="http://localhost:4000/lib/tellbrowser-client.min.js"></script>

Here's a usage example using notifyjs:

<!-- The following libs are indeed served by the app for maximal convenience. -->
<link href="http://localhost:4000/lib/bootstrap/css/bootstrap.min.css" rel="stylesheet" media="screen">
<script src="http://localhost:4000/lib/jquery/jquery.min.js"></script>
<script src="http://localhost:4000/lib/notifyjs/notify-combined.min.js"></script>

<script>
    window.addEventListener('load', function () {
        var client = new TellBrowser('http://localhost:4000/');

        client.listen(function (msg) {
            // We're assuming the server sends simple strings.
            $.notify(msg, { autoHide: false, className: 'info' });
        });
</script>

Just send a POST request to http://localhost:4000/tellbrowser/<key> where <key> is the value of the TellBrowserKey cookie. The body of the request can be any JSON object.