Get logged in user info from another website

I’m already using discourse connect where I allow members of specific group to sign in to my website using discourse.
I do have a composer right in my react app to allow user to create topic directly from my react app without needing to create an account in my react app. So I need to know the user info who is logged in on discourse.
The problem with SSO is that it requires a full page reload which I need to avoid to make my feature work.