I just finished adding support for a WebSocket based notification service to Tsugi. It is not a full-up WebSocket server or SocketIO server where you can put a bunch of business logic and data storage in the socket server – it is just a low-latency notification service that can be used to make applications quicker and more efficient compared to techniques like polling. Here is some documentation on the approach:
http://do1.dr-chuck.com/tsugi/phpdoc/Tsugi/Core/WebSocket.html
Here is a simple test harness that exercises Web Sockets that you can run in your Tsugi:
https://github.com/tsugiproject/socket-test
Here is a more complete chat application with messages, presence, and history and uses notification to work better. It functions whether or not WebSocket notification is available – it is just more sluggish and has a performance impact when WebSockets are not available:
https://github.com/tsugitools/michat
You can play with the Chat tool at:
https://www.tsugicloud.org/tsugi/store/details/michat
I am going to record a walkthrough video of socket-test and michat sometime soon.