app.js

var app = angular.module('someApp', [
  'ngCookies',
  'ngResource',
  'ngSanitize',
  'ui.bootstrap',
  'ui.router'
]);

// (Routes not here for brevity)

app.config(['$httpProvider', function($httpProvider) {
        $httpProvider.defaults.useXDomain = true;
        $httpProvider.defaults.withCredentials = true;
        delete $httpProvider.defaults.headers.common['X-Requested-With'];

        $httpProvider.interceptors.push('notLoggedInInterceptor');
  }
]);

// register the interceptor as a service
app.factory('notLoggedInInterceptor', function($q, $location, $rootScope) {
  return {
    // optional method
    'request': function(config) {
      // do something on success
      return config || $q.when(config);
    },

    // optional method
   'requestError': function(rejection) {
      // do something on error
      return $q.reject(rejection);
    },

    // optional method
    'response': function(response) {
      // do something on success
      return response || $q.when(response);
    },

    // optional method
   'responseError': function(rejection) {
      // do something on error
        console.log('Response Error caught.');
        if(rejection.status === 401){

          if($location.path() == '/login' && rejection.config.method == "POST") {
            toastr.error('Please try again','Login failed!')
          };

          $rootScope.user = {};
          $rootScope.redirectTo('/login');

          if($location.path() != '/'  && $location.path() != '/login'){
            var deferred = $q.defer();

            var req = {
              config: rejection.config,
              deferred: deferred,
              location: $location.path()
            };

            $rootScope.requestsUnauthenticated = req;

            return deferred.promise;

          }

        }
        else if(rejection.status === 403){

          $rootScope.redirectTo('/dashboard');

          return $q.reject(rejection);
        }else{
          return $q.reject(rejection);
        }
    }
  };
});


app.config(function ($locationProvider) {
  $locationProvider.html5Mode(false); //change this to switch between hashbang mode and html5 mode
});

app.run(function($rootScope, $http, $location, $timeout) {

    // Handling of 401
    $rootScope.requestsUnauthenticated = null;

    // I have not the slightest clue why Angular is hiding $location while routing sometimes.
    $rootScope.redirectTo = function(path) {
      $timeout(function() {
        $rootScope.$apply(function() {
          $location.path(path);
        });
      })
    };

    /**
    * On ‚event:loginConfirmed’, resend all the 401 requests.
    * Which have been intercepted by unauthenticated-filter
    */
    $rootScope.$on('event:loginConfirmed', function() {
      console.log('LoginConfirmed invoked.');
      var request = $rootScope.requestsUnauthenticated;

      if(request){
        retry(request);
      }else{
        // redirect to dashboard
        $rootScope.redirectTo('/dashboard');
      }

      $rootScope.requestsUnauthenticated = null;

      function retry(req) {
        $http(req.config).then(function(response) {
           req.deferred.resolve(response);
           $rootScope.redirectTo(req.location);
        });
      }
    });

});

});

Authentication.js

app.factory('Authentication', function($http, $rootScope, $location, $timeout){

    var Auth = {};

    Auth.unsetUser = function() {
        $rootScope.user = {};
    };

    Auth.setUser = function(data) {
        $rootScope.user = data;

        // Determine if user is admin
        $rootScope.user.isAdmin = false;

        for (var i = $rootScope.user.roles.length - 1; i >= 0; i--) {
            if($rootScope.user.roles[i].name == 'Administrator'){
                $rootScope.user.isAdmin = true;
                break;
            }
        };
    }

    Auth.load = function(){
        $http.get(API_SERVER_HOST+'/login')
            .success(function(data, status) {
                console.log('Call completed with status '+status+' and data '+JSON.stringify(data));
                if(status == 200)
                {
                    Auth.setUser(data);
                }
                else
                {
                    console.log('Auth.load status: '+status);
                    Auth.unsetUser();
                }
            })
            .error(function(data, status) {
                Auth.unsetUser();
                console.log('Call completed with status '+status+' and data '+JSON.stringify(data));
            });
    };


    Auth.login = function(credentials){
        $http.post(API_SERVER_HOST+'/login', credentials).success(function(data, status) {
            if(status == 200){
                Auth.load();
                console.log('Already logged in! User: '+JSON.stringify($rootScope.user));
            }else{
                console.log('Call completed with status '+status+' and data '+JSON.stringify(data));
                Auth.setUser(data);
                $rootScope.$broadcast('event:loginConfirmed');
            }

        })
        .error(function(data, status) {
            Auth.unsetUser();
            console.log('Call completed with status '+status+' and data '+JSON.stringify(data));
        });;
    };


    Auth.logout = function(){
        $http.get(API_SERVER_HOST+'/logout').success(function(data,status) {
            Auth.unsetUser();
            console.log('User logged out!');
            $timeout(function() {
                $rootScope.redirectTo('/login');
            });
        }).error(function(data, status) {
            Auth.unsetUser();
            console.log('Logout failed!');
        });
    };

  return Auth;
});