update $scope info from another controller - angularjs

Question

How can i make the testservice factory return the result from the post request?, or make the app, factory update some $scope details thats within the overallcontroller ?
how can i update information within the overallcontroller from another controller?
app.factory('testservice', ['$http', 'auth', function($http, auth) {
var o = {
posts : []
};
o.test = function() {
return $http.post('/poster', null, {
headers: {Authorization: 'Bearer '+auth.getToken()}
}).success(function(data){
console.log(Data);
});
};
return o;
}]);
app.controller('overallController', ['$scope', 'posts', 'testservice', 'auth','$interval',
function($scope, posts, testservice, auth, $interval) {
$scope.data = {cash:"12879999",location:"test2",gang:"None","username":"test",
xp: 1290,
health: 100,
wanted: 30,
energy: 90};
var databackground = function() {
console.log("logging...");
var t = testservice.test;
console.log(t);
}
databackground();
$interval(databackground, 30000);
}]);
example html
<div class="main" ng-controller="overallController">
<section class="sides left" style="background:blue; height:100px;">
<ul>
<li ng-hide="isLoggedIn()">Logg inn</li>
</ul>
</section>
<div ng-controller"othercontroller">
// call made from some code here
</div>
</div>

Answer 1

Change your service to
o.test = function() {
return $http.post('/poster', null, {
headers: {Authorization: 'Bearer '+auth.getToken()}
}).then(function(response){
return response.data;
});
};
And in your controller, do call the service, and get the results back in the promise:
testservice.test().then(function(data) {
$scope.data = data;
});
Read more about how to use promises here

Answer 2

You return the promise from your service, you would listen for that to resovle and get hold of your data.
Using $rootScope is heavy handed approach and should be used as a last resort. Services and event are preferable.
var databackground = function() {
console.log("logging...");
testservice.test()
.then(function (res) {
console.log(res.data); //Here is your data
});
}
EDIT: Your service should change slightly also. Firstly .success and .error are deprecated. Use .then and .catch instead.
If you wish to just return data out of your service just do:
o.test = function() {
return $http.post('/poster', null, {
headers: {
Authorization: 'Bearer ' + auth.getToken()
}
});
};
However if you want to transform the data in your service you can but ensure your return it or your controller wont get anything:
o.test = function() {
return $http.post('/poster', null, {
headers: {
Authorization: 'Bearer ' + auth.getToken()
}
})
.then(function (res) {
res.data.test = 'lol';
return res;
})
};

Answer 3

Try referencing $rootScope instead of $scope.
This will allow controllers and factories to interact with each other.