Accessing currentUser in Angularjs - angularjs

Question

I currently have the following code in my app.js config which is used on secure routes:
var checkLoggedin = function($q, $timeout, $http, $location, $rootScope){
// Initialize a new promise
var deferred = $q.defer();
// Make an AJAX call to check if the user is logged in
$http.get('/api/loggedin').success(function(user){
// Authenticated
if (user !== '0')
$rootScope.user = user; //IS THIS ADVISABLE???
$timeout(deferred.resolve, 0);
// Not Authenticated
else {
$timeout(function(){deferred.reject();}, 0);
$location.url('/login');
}
});
return deferred.promise;
};
The back end returns the user object.
I would like to be able to access the current user from different controllers and wondered whether I should make use of $rootscope (as shown above) or whether a Service would be the way to go.
Any code samples would be much appreciated if Service is the way forward.

Answer 1

If you only want to use your user variable in the views, reading from the rootScope is fine. However, if you in a controller want to use that user for something, you can't read it directly from the rootScope, as that variable may not yet have been set by your checkLoggedin function.
For instance, if you have code like this in a controller
.controller('NavbarCtrl', function ($scope, $rootScope) {
if ($rootScope.user) {
// do logged in stuff
}
//...
it may fail, as the promise has not yet set the user variable in the rootscope.
It's a bit annoying, but to guarantee that the variable always is set, one will need to reed it as a promise. So I would try to always access the logged in user through a service.
.service('PersonService', function ($http) {
return {
getCurrentUser: function() {
return $http.get('/api/person/me', {cache: true});
// or you can use something similar to your code above
}
}
});
Is an example. As you can see, I have enabled cache, so multiple calls to the function will not create new calls to the back end.
Then use it like this:
.controller('NavbarCtrl', function ($scope, PersonService) {
PersonService.getCurrentUser().success(function(user) {
$scope.user = user;
// or maybe do something else
$scope.showButton = user.permissionLevel > 5;
});
// .....