It’s not so easy to get *ns* string in ClojureScript as you might expect but here is a tip.
It is impossible to get *ns* string at run-time in ClojureScript (except in self-hosted ClojureScript) but it can be accessed at compile-time only. So you have to use a macro to get it as the following example.
I came up with this idea in the course of implementing set-ns-blacklist! and set-ns-whitelist! (https://github.com/philoskim/debux#debux-config) in my debux library.