How to find UserName in a custom visual

Thanks for your reply Sam!!

No, I'm not looking for the USERNAME() DAX function. I'm actually looking for a simple way to get the username from my custom visual's JavaScript code.

When I view the page source of the PowerBI webpage, I see the below global JavaScript object taht actually has the username.

But I'm not 100% sure if I can rely on that object, so that it might not change in future breaking my code.

var powerbi = {
        session : {
            userInfo: {
                name:  '[email protected]',
                givenName: xxxxx,
                surname: xxxxx,
                puid: xxxxx,
                uoid: xxxxx,
                alternateEmail: ''
            }
        }
    };