🐱📲 Push notifications with cats and Polymer
HTML JavaScript CSS
Switch branches/tags
Nothing to show
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Failed to load latest commit information.



Send 🐱to browsers around the world using push notifications. Behind the scenes it uses a Polymer platinum-push-messaging element that registers a browser for push notifications, and a node server that collects all the registered clients and sends them cats.

Play with it

In the wild, this lives on a heroku free dyno, so it gets restarted often and drops all of the registered browsers. Not sure that's such a bad thing. You can:

  • register your browser to use push notifications, and receive cats when they are sent out
  • send cats to all the registered clients. The server will only send one cat a minute, because I don't trust all y'all internet people to not spam me.


Configure it

There are three items that need to be configured. The ID of your Google Developer Console project, the corresponding API key, and the URL of your MongoDB database.

To find the first two, enable the API through the getting started flow. Ignore that it says it is setting up an Android project, and ensure that you enable Google Cloud Messaging.

You can either set up your own MongoDB server, or add one to your heroku app with:

heroku addons:create mongolab

You can then see the URL of your instance with

heroku config.

Now you need to add a file:

  • a .env file in the root of your project, that contains your config values. This sets the config that should be used by the Heroku foreman tool. It should look something like this:

If you want to publicly deploy your app to Heroku you will also need to set the config values on your live app:


Install it

This uses npm for the node server bits, and bower for the client side Polymer bits (in particular platinum-push-messaging, without which I would have had to slave for days over service worker code. 💖)

npm install
bower install

Run it

You start the server with

node server.js

This code is also heroku ready, so you can also start it with

foreman start

In your browser, open two tabs:

  • index.html, which lets the browser register for push notifications. You will have to enable push notifications for this to work.
  • meow.html which sends the notifications (let's be honest: the cats) to all the registered clients. It should also tell you how many clients are registered.

Then watch the 🐱 roll in.