Rails 5: Action Cable Demo
Action Cable is the highlight feature of Rails 5. It makes it very easy to work with WebSockets in Rails. You have access to your full domain model and everything is neatly abstracted on both the server and client side.
Action Cable is what drives the chat, notification, and other live features in Basecamp 3. It was extracted directly from that use.
I made a brief tutorial showing how it works. Enjoy!