Error handling when data is not resolved in Angular UI router - angularjs

Question

I am using angular-ui-router's resolve to get data from server before moving a state. I want to inform user if the request has failed. I have service that will response error the request has failed. My question is how can I detect the failure in ui-router resolve and trigger some Modal service like pop up.
I have read some related posts online, but I am still confused how to make it happen. Thanks in advanced!
Config and Service:
angular.module('myApp',['ui.router', 'ngAnimate', 'ui.bootstrap'])
.config(function ($stateProvider, $locationProvider) {
$locationProvider.html5Mode(true);
$stateProvider
.state('customer', {
url: '/customer',
templateUrl: '/customer.html',
controller: 'CustomerCtrl',
resolve: {
/*
* How to inject CustomerService here
* How to catch the server error
* How to trigger a popup
*/
data: cusomter_data
}
});
})
.service('CustomerService', function($http, $q) {
return ({
getGeneral: getGeneral
});
function getGeneral(customer_id) {
var request = $http({
method: "get",
url: '/customer',
params: {
customer_id: customer_id
}
});
return (request.then( handleSuccess, handleError));
}
function handleError (response){
if (!angular.isObject(response.data) || !response.data.message) {
return($q.reject("Failed to retrieve customer information."));
}
return($q.reject(response.data.message));
}
function handleSuccess(response) {
return (response.data);
}
});

Answer 1

After some research, I found out a solution by creating a errorModal service and inject it to resolve. Here is my solution.
$stateProvider
.state('customer', {
url: '/customer',
templateUrl: '/customer.html',
controller: 'CustomerCtrl',
resolve: {
data: function(CustomerService, SelectedCustomerService, errorModalService) {
var shared = SelectedCustomerService;
return CustomerService.getData(shared.customerid).then(
function (data) { return data; },
function(error) {
var modalOptions = {
closeButtonText: 'Close',
headerText: 'Customer Error',
bodyText: error
};
errorModalService.showModal({}, modalOptions);
}
);
}
}
});