app.js snip

.run(['$cookies', 'user', 'forge', function($cookies, user, forge){

        //Check for cookies.
        var token = $cookies["X-Shrug-Token"];
        if( token ) {
            forge.sessions.get({id: token},
            function success(data) {
                user.login(data);
            },
            function error() {
                user.logout();
            })
        }   else {
           //clear
           console.log('no token');
           user.logout();
        }



    }]);

login_controller.js

'use strict';

appCtrl.controller('LoginCtrl',['$scope','forge', 'user', '$route', '$location', function($scope, forge, user, $route, 
    $location) {

    $scope.login = function (){
        $scope.authError = null;

        forge.login($scope.username, $scope.password).then(
            function success(response) {
                if(response && response.data) {
                    user.login(response.data);
                   
                    $scope.username = $scope.password = null;
                    $route.reload();
                }
            },
            function error(response) {
                console.log(response);
                if(response && response.status===401) {
                    $scope.authError = 'Access Denied. Try Again.';
                }else{
                    // problem with request to server
                    $scope.authError = 'Login Server offline, please try later';    
                }
            
            });


    },
    $scope.logout = function(){
        user.logout();
        $location.path('/');

    }

}]);

sessions_controller.rb

class Api::SessionsController < Devise::SessionsController
  
  before_filter :authenticate_user!, :except=>[:create]

  respond_to :json
  def show
    
    render  :status => 200,
            :json => { :success => true,
                      :info => "Logged in",
                      :user => current_user,
                      :auth_token => current_user.authentication_token }
  end


  def create
    resource = warden.authenticate!(:scope => resource_name, :recall => "#{controller_path}#failure")
    render :status => 200,
           :json => { :success => true,
                      :info => "Logged in",
                      :user => current_user,
                      :auth_token => current_user.authentication_token }
  end

  def destroy
    warden.authenticate!(:scope => resource_name, :recall => "#{controller_path}#failure")
    current_user.update_column(:authentication_token, nil)
    sign_out
    render :status => 200,
           :json => { :success => true,
                      :info => "Logged out",
                      :csrfParam => request_forgery_protection_token,
                      :csrfToken => form_authenticity_token

           }
  end

  def failure
    render :status => 401,
           :json => { :success => false,
                      :info => "Login Credentials Failed"
          }
  end


end

user.js snip

 var service = {
        login: function(sessionData){
          // console.log(sessionData);

          $cookies["X-Shrug-Token"] = sessionData.auth_token;
          $http.defaults.headers.common['X-Shrug-Token']=sessionData.auth_token;
          tokenHandler.set( sessionData.auth_token );

          $rootScope.loggedUser = new forge.users(sessionData.user);
           // console.log($rootScope.loggedUser);

          $rootScope.$broadcast('user_login', $rootScope.loggedUser)

        },

        logout: function() {
            var session = $cookies["X-Shrug-Token"];
            delete $cookies["X-Shrug-Token"];
            tokenHandler.clear();
            session && forge.sessions.delete({id: session}, 

                function(data) {
                 
                  $http.defaults.headers.common['X-CSRF-Token'] = 
                    data["csrfToken"];
                  
                }, {});
            $rootScope.loggedUser = null;
            $rootScope.$broadcast('user_logout', $rootScope.loggedUser)

        }

    }
    return service;