TLS是否在整个wss连接中使用或仅在连接时使用？

I plan to write an secure websocket server in golang. My question is:

Is TLS used throughout the entire connection when using wss://, or is it just used when upgrade from http(s) to websocket protocol?

The reason I ask is that as I understand the websocket protocol has nothing to do with http except that the connection is initiated via http(s).

So, if I use ListenAndServeTLS in my Go program, can I ensure that the entire websocket conversation is secure?