How to get Google UserId from active user session in App Maker?

Question

Is there a way to get "User Google Id" from the session in App Maker. In the documentation its only mentioned how to retrieve the email of the logged in user Session.getActiveUser().getEmail() but no where it says how to get the id. I need this because the user email might sometimes changes. So I need the user id to keep track of users and related permission tasks. Or is there something I'm missing out here in how this should be implemented.

Answer 1

A team member has figured it out. This should be done using Apps Script - which works within App Maker environment using server side script.

var GoogleUser = (function (){

    /**
     * 
     * @param {string} email
     */
    function getUserObjByEmail(email){

        // Same as using AdminDirectory class.
        var apiUrl = "https://www.googleapis.com/admin/directory/v1/users/"+email+"?fields=id";
        var token = ScriptApp.getOAuthToken();
        var header = {"Authorization":"Bearer " + token};
        var options = {
            "method": "GET",
            "headers": header
        };

        var response = JSON.parse(UrlFetchApp.fetch(apiUrl, options));
        return response;
    }


    /**
     * 
     * @param {string} email - User email.
     */
    function getIdByEmail(email){
        return getUserObjByEmail(email)['id'];
    }

    var publicApi = {
        getIdByEmail: getIdByEmail
    };

    return publicApi;
})();

Note that using var apiUrl = "https://www.googleapis.com/admin/directory/v1/users/"+email+"?fields=id"; is not going to be asynchronously called because its already happening in the server.