I am new to ReactJS and trying to figure out a good design but couldn't reach a decision from Googling. Here is my problem:

I have some old JavaScript code that deals mostly with my app's WebSocket logics and a little bit of DOM manipulation using the WebSocket data. I wanted to refactor those code into React component because they seem much cleaner and maintainable. But from what I have gathered, React components are used for rendering HTML elements, which leaves me wondering whether it makes sense to have some pure logical React components that renders nothing or to keep all WS logic in my old JS and only refactor the parts that requires rendering.

Thanks!