Resource file is undefined on scope - angularjs

Question

I have a resource file that sometimes is read, and sometimes is undefined and crashes all the application. I do not know why it only works sometimes and it is causing me trouble to figure a solution out. On my controllers I am passing the service that I created to read the file which is appResourcesService:
app.controller('CommonController', ['$scope', '$location', 'appResourcesService',
function ($scope, $location, appResourcesService)
And the service to read resoruces is the following:
'use strict';
app.factory('appResourcesService', ['$resource', function ($resource) {
var appResourcesServiceFactory = {};
appResourcesServiceFactory.getResources = function ($scope, language, locale) {
var languageFilePath = 'resources/AppResources.json';
$resource(languageFilePath).get().$promise.then(function (data) {
$scope.appResources = data;
}, function (reason) {
var defaultLanguageFilePath = 'resources/AppResources.json';
$resource(defaultLanguageFilePath).get(function (data) {
$scope.appResources = data;
});
});
};
return appResourcesServiceFactory;
}]);
Like I said, sometimes it works without any kind of problem, but sometimes when in the controller I reach the piec eof code $scope.appResources, appResources is undefined. I think it is maybe because it reaches there before the file is read, but I am not being able to find a solution to avoid it.

Answer 1

Your factory should return a promise.
It's the job of your controller to handle data. (I use $http as it's cleaner)
app.factory('appResourcesService', ['$http', function($http) {
var appResourcesServiceFactory = {};
appResourcesServiceFactory.getResources = function () {
var languageFilePath = 'resources/AppResources.json';
return $http.get(languageFilePath).then(function(response) {
return response.data;
});
)};
return appResourcesServiceFactory;
}]);
You resolve the promise inside the controller with .then to get the data and set your scope.
appResourcesServiceFactory.getResources().then(function(data) {
$scope.appResources = data;
})