401_interceptor.js

app.config(function($httpProvider) {

  $httpProvider.interceptors.push(function($q, $location) {
    return {
      // Reject unauthenticated requests
      responseError: function(rejection) {
        if (rejection.status === 401) {
          $location.nextAfterLogin = $location.path();

          //prevent redirect to login or logout after login
          if ($location.nextAfterLogin === '/logout' ||
            $location.nextAfterLogin === '/login') {
            delete $location.nextAfterLogin;
          }

          $location.path('/login');
        }
        
        return $q.reject(rejection);
      }
    };
  });
});