How can I add logged in user

[M By]

This is my get api call that returns me the current logged in user

AJS.$.ajax({
    url: "/rest/auth/latest/session",
    type: 'GET',
    contentType: 'application/json',
    async: true,
    success: function(data) {
        user = data.name;

    }
});

 I tried AJS.params.loggedInUser.How can I do that?