title: Save Azure Active Directory user id
body: <p>I'm looking for the best practice way of saving user identification data in my MVC application. Users authenticate onto the site using Azure AD. When a user saves data I want the "user id" to be saved on that record to uniquely identify it and also allow users to return their own set of data.</p>
  
  <p>What is the best method to get the users AD unique identifier?</p>