AngularJS Directive data binding not happening from controller - angularjs

Question

I am facing the problem of data binding from controller to directive because of delay in response from the server.
To better understand just see a small program below.When I remove the timeout function, binding happens.
<msg track="{{customer}}"></msg>
angular.module('myApp').directive('msg', function() {
return {
scope: {
track :"#"
},
link : function(scope, element, attrs) {
},
template : "<a href>{{track}}</a>"
}
});
angular.module('myApp').controller('HomeCtrl', ['$scope', function($scope) {
setTimeout(function() {
$scope.customer = "shreyansh";
}, 5000);
// assume some service call inside controller
// service1.getData().then(function(data){$scope.customer = data})
}]);
How can i fix above problem so that above code should render as
<msg track="shreyansh" class="ng-isolate-scope">shreyansh</msg>.
Any help is appreciated.
Thanks

Answer 1

var app = angular.module('plunker', []);
app.factory('myService', function($http) {
var promise;
var myService = {
getData: function() {
if (!promise) {
promise = $http.get('test.json').then(function(response) {
return response.data;
});
}
return promise;
}
};
return myService;
});
app.controller('MainCtrl', function(myService, $scope) {
myService.getData().then(function(d) {
$scope.data = d;
});
});
app.directive('msg', function() {
return {
restrict: 'E',
scope: {
track: "#"
},
link: function(scope, element, attrs) {
},
template: "<a href>{{track}}</a>"
}
});
<msg track="{{data.name}}"></msg>
test.json file
{
"name": "Pete"
}