I'm working on a UML project and needed a tool to render State Machine Diagram on a website. I found this cool API but I don't understand how to use it, I'm very new to Node js.

Basically I would like to understand how this website works.

My goal is to be able to pass a .smcat (or JSON) file to the server and call the render function to display the generated svg on my application each time there is a modification on it.