you can find a ruleset for websecockets in the MWG Ruleset Library. Websocket handling is activated with an Event in a rule.
You may add this rules after the user authentication to enable websockets based on user/Groups.
show a screenshot or manual pls.
You can find the Rule in the Library as Troja mentioned.
Add -> Rule Set from Library -> Common Rules -> WebSocket Handling
This is pretty much straight forward. It enables the WebSocket Handling, after that you can allow sites/clients/users to use WebSockets and block for all others.