Auto Authenticate a external user and display the Power BI Report/Dashboard

Hey Guys,

I am new to Power BI.

I have  requirement where the power BI report needs to be accessible only by users external to the power BI account. (Power BI Embedded to Web Portal)

1. Let's say I have created a online web portal which has Login Credentials.

2. I will then embed the Power BI report in one of the pages of the Web Portal using the "Publish to Web" option.

Is there a way to auto authenticate the User and display the dashboard without asking them to Create/Login to a Power BI account?

Anybody else with the link should essentially not be able to access the Power BI report.

I also do not want to add the users Manually in User's Role (as this is not feasible for many users). 

Can I keep a seperate table not related to any of the other tables which contains a list of usernames Example:([email protected]) which the report can use as reference with maybe USERNAME() or USERPRIINCIPALNAME() DAX function to check the user before displaying the report.