AngularJS service with HTTP request, offline status - angularjs

I have a AngularJS app with a service that load a HTTP request, that works all fine, but...
When my app is offline at the beginning, i show a "offline" page with a retry button, when i click the button and the APP is online I need the service to load the data.
The problem is that nothing happen when I click the button, the online check works fine but the web service is never called :(
my service:
.service('webService', function ($http, $q){
var defferer = $q.defer()
var webservice_url = "http://mywebservice_url/";
$http.get(webservice_url+"?action=get_settings").success(function(data) {
defferer.resolve(data);
});
return defferer.promise;
})
my controller:
.controller('NetworkCtrl', function($scope, $location, $timeout, webService) {
$("#tryagain-button").click(function(e) {
e.preventDefault();
if(checkifonline()) {
webService.then(function(data) {
$scope.data = data;
});
}
});
})

First of all, using jQuery within an controller is absolutely not how angularjs works. Use the ng-click directive. Even if your service would be implemented correctly, it wouldn't work since AngularJS will not get notified about model changes in the scope (you would need to use $apply, but just stick to the ng-click directive)
Second, the service function takes a constructor function. Within this constructor you're making an http request (while you're offline) and the promise is resolved. You will never make a new request, since the service always retuns the same promise. Your service should look like:
.service('webService', function ($http){
var webservice_url = "http://mywebservice_url/";
this.getSettings = function(){
return $http.get(webservice_url+"?action=get_settings");
};
})
and your controller:
.controller('NetworkCtrl', function($scope, $location, $timeout, webService) {
$scope.onClick = function(){
webService.getSettings().success(function(data){
$scope.data = data;
}
}
})
and your HTML button:
<button ng-click="onClick()">reload</button>

Related

In an Angular.js controller's scope function code doesn't run below a $timeout statement inside

I have a button for which I have set ng-click="refresh()". The console logs before the timeout function logs correctly but the console log inside the $timeout block and after the block doesn't seem to log. If I remove the $timeout block every console log works. I even checked with $interval instead of $timeout but same behaviour.
I wanted to do something like this here
I'm using Angular.js 1.4.0
This is my implementation inside the controller
$scope.refreshing ={state: false};
$scope.refresh = function(){
console.log($scope);
$scope.refreshing.state = true;
$scope.search(); //sends an http request and loads results.
console.log('this logs');
// $scope.refreshing.state = false;
$timeout(function(){
console.log('this doesnt log')
$scope.refreshing.state = false;
},2000);
console.log('this doesnt log')
}
You'll want to make sure your dependency injection is wired up properly. For example:
angular
.module("MyApp")
.controller("MyController", ["$scope", "$timeout", MyController]);
function MyController($scope, $timeout) {
// controller code
}
See John Papa's AngularJS style guide for some best practices relating to controllers.

Angular JS: Uncaught SyntaxError: Unexpected token

I have one error in $http.json line.
Here is my code:
var myApp = angular.module('myApp', ["ionic"]);
myApp.service("Pressed", ["$http", "$log", Pressed]);
myApp.controller("AppCtrl", ["$scope", "Pressed", "$log", AppCtrl]);
function AppCtrl($scope, Pressed, $log){
$scope.refresh = function(){
Pressed.getBlogs();
}
}
function Pressed($http, $log) {
this.getBlogs = function() {
$http.jsonp('http://oasisgroups.com/oApp/product.php?callback=JSON_CALLBACK()')
.success(function(result){
$log.info(JSON.stringify(result.product));
});
};
}
When I click on refresh button, an error is displayed in the console:
You can also here find the respective service.
I believe the main issue is that the service doesn't seem to support a jsonp call. No matter how I call the service you provided it only responds with standard JSON results and not with the JSON wrapped in the callback function. Your screen shot of Chrome even shows the raw JSON, not JSONP response from the service. If a service doesn't support JSONP you can't force it to, that is something each service does on a case by case basis depending on how it is written. So the root cause of your error is that AngularJS is expecting the callback function to be part of the response, it cannot find it, and you get the error you are seeing.
I have constructed a jasmine test for your code and it passes. That is the best I can do to confirm that your code is correct and the issue is outside of your Angular code.
Unless the web service actually responds with the expected callback function wrapping the JSON, you need to switch to a standard $http.get() and deal with any potential XSS issues that you might encounter in a different way.
You can see a working JSONP example with this url. You will note that it starts with "getdata" and then wraps the JSON content inside that function's (). Your service is not doing that with the callback query string attribute.
var myApp = angular.module('myApp', []);
myApp.controller("AppCtrl", ["$scope", "Pressed", "$log", function ($scope, Pressed, $log) {
$scope.refresh = function () {
Pressed.getBlogs($scope);
}
}]);
myApp.service('Pressed', ['$http', '$log', function ($http, $log) {
var pressed = {};
pressed.getBlogs = function ($scope) {
$http.jsonp('http://oasisgroups.com/oApp/product.php?callback=JSON_CALLBACK')
.success(function (data,status,headers,config) {
$log.info(JSON.stringify(data));
$scope.products = data.product;
console.log('Found ' + data.product.length + ' products');
})
.error(function () {
console.log("Error during http get request.");
});
};
return pressed;
}]);
Then the test would look something like this:
describe('bad_jsonp', function () {
var service, scope;
beforeEach(module('myApp'));
beforeEach(angular.mock.inject(function ($rootScope) {
scope = $rootScope.$new();
}));
beforeEach(inject(function($httpBackend, _Pressed_) {
backend = $httpBackend;
service = _Pressed_;
}));
it('test that service response contains the attribute product', function () {
backend.expect("JSONP","http://oasisgroups.com/oApp/product.php?callback=JSON_CALLBACK").
respond(200,
{"success":1,"msg":"success","product":[{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/160112WP_20160112_17_57_49_Pro__1452604019_113.193.193.146.jpg","title":"Shreenath Ji"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/1601124e199090-c030-4f01-be11-c5140cf20273__1452603831_113.193.193.146.jpg","title":"Acrylic Jali"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/1601128a718e95-7df0-4189-876e-204b715cf90d__1452603868_113.193.193.146.jpg","title":"Acrylic Jali"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/16011229b095c9-b897-4942-831f-92073f527374__1452603895_113.193.193.146.jpg","title":"Wooden Decorative"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/16011255ce3155-3956-4cfb-8dd5-39021713d350__1452603914_113.193.193.146.jpg","title":"Acrylic Jali Oranage"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/160112WP_20160112_17_33_11_Pro__1452603994_113.193.193.146.jpg","title":"Acrylic Jali Green"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/160112607c733c-8dd5-442c-a584-6179339abb0e__1452603974_113.193.193.146.jpg","title":"Acrylic Jali White"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/160112300cca44-e783-48f7-b035-59ef0529ad53__1452603956_113.193.193.146.jpg","title":"Wooden Decorative"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/16011279e7c001-6663-4dfe-91ce-70cc87e6ca2d__1452603940_113.193.193.146.jpg","title":"Wooden Decorative"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/160112WP_20160112_17_58_35_Pro__1452604069_113.193.193.146.jpg","title":"Corian Design "},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/160112WP_20160112_17_59_14_Pro__1452604098_113.193.193.146.jpg","title":"Corian Design "},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/160112WP_20160112_18_00_34_Pro__1452604138_113.193.193.146.jpg","title":"AalaBuster"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/160112WP_20160112_18_01_20_Pro__1452604320_113.193.193.146.jpg","title":"AalaBuster"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/160112WP_20160112_18_02_08_Pro__1452604343_113.193.193.146.jpg","title":"Corian wash basin"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/160112WP_20160112_18_02_25_Pro__1452604370_113.193.193.146.jpg","title":"3d Corian Design"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/160112WP_20160112_18_02_43_Pro__1452604393_113.193.193.146.jpg","title":"3d Corian Design"},{"image":"http:\/\/oasisgroups.com\/images\/oacgallery\/160112WP_20160112_18_03_13_Pro__1452604424_113.193.193.146.jpg","title":"3d Wooden Decorative"}]}
);
expect(service).toBeDefined();
service.getBlogs(scope);
backend.flush();
console.log(scope.products);
var products = scope.products;
expect(products.length).toBe(17);
expect(products[0].title).toBe("Shreenath Ji");
});
});
The test doesn't include the actual callback in the response content because the mocking framework handles that wrapping and unwrapping for you just like AngularJS does in the first place, so it isn't an exact test but it is as close as I can get with what we have.

How to make controller wait untill app.run finishes

In my application, I'm getting some data in app.run using $http.get()
The result from this is required to proceed to the controller.
Currently my controller is executing before the completion of this $http.get
How can I make my controller's execute after the execution of $http.get()
app.run(function ($rootScope, $http, $cookies) {
var currentLanguageId = angular.fromJson($cookies.get('mykey')).UserInfo.Country;
$http.get('myurl').then(function (serviceInfo) {
$rootScope.serviceURL = serviceInfo.data.serviceURL;
}, function (error) {
alert('error service info');
});
run can't handle asynchronous work at the moment. See this issue : https://github.com/angular/angular.js/issues/4003
You have multiple solutions for that. You can get your data without Angular and start Angular manually ( How to wait for a promise in a Run block in Angular? )
Or you can use the resolve of your route to do this : AngularJS : Initialize service with asynchronous data
You can use angular scope event. When data is fetched, you can broadcast an event from $rootScope to all controllers and receive this event in target controller.
You may use $rootScope.$broadcast();in the app.run and then use $rootScope.$on() in your controller.
app.run(function ($rootScope, $http, $cookies) {
var currentLanguageId = angular.fromJson($cookies.get('mykey')).UserInfo.Country;
$http.get('myurl').then(function (serviceInfo) {
$rootScope.serviceURL = serviceInfo.data.serviceURL;
$rootScope.$broadcast('serviceInfoReceived')
}, function (error) {
alert('error service info');
});
});
In your Controller
app.controller ('myCtrl' , function($rootScope) {
$rootScope.$on("serviceInfoReceived", function(){
console.log($rootScope.serviceURL)
});
})
Hope this may help you.
This is an old question, however the $rootScope.$on solution will not always work. It will depend on the timing of the controller registering the listener. The way I have found that works is to set a $rootScope property, and then configure a recursive timeout to wait for it to be set.
function waitForRun() {
if($rootScope.runFinalized){
// do something
} else {
$timeout(waitForRun, 500)
}
}
waitForRun();
and after the last .run block:
.run(function($rootScope) { $rootScope.runFinalized = true; })
Ugly, but it works.

how can refresh my scope after ajax call

I am newbie for angularjs.I have list of persons and each person have edit and delete button. when i click to edit button ng-dialog box was open and show person details and person can change and save information on database,behind save button ajax call trigger and update information on database.
Updating information on database work well but on UI side my view doesn't reflect my database changes.
I had tried to apply "$scope.$apply();" method but i got error message "$digest already in progress".
Please help me,how can refresh my scope after ajax call.
You can use shared service for that and broadcast any event through this service. Broadcasted event can be listened in any controller with $scope.$on.
For example:
angular.module("app", []).factory("sharedService", function($rootScope){
var mySharedService = {};
mySharedService.values = {};
mySharedService.personWasUpdated = function(){
$rootScope.$broadcast('update');
}
return mySharedService;
});
Ctrl for person editing.
app.controller('personEditController', ['$scope', 'sharedService', '$http', function ($scope, sharedService, $http) {
$scope.updatePerson = function(newPerson){
$http.post("../some URL/..", {person: newPerson})
.success(function(data){
sharedService.personWasUpdated(); //event broadcasing
})
};
}
Ctrl for displaying list of persons.
app.controller('personController', ['$scope', 'sharedService', '$http', function ($scope, sharedService, $http) {
var loadPersonsData = function(){
$http.get("../some URL/..").
.success(function(data){
$scope.persons = data;
})
};
loadPersonsData(); //first load
$scope.$on('update', function () {
loadPersonsData(); // load after update of any person
});
}
Try with $scope.$digest(); or use $http instead jQuery ajax or others

How to call controller method from service in Angular?

I wonder if I can call controller method from service.
I know that Service is singleton and I can't inject $scope to the service.
In my case I manage Google Maps in service and want to open modal Dialog when user right clicks on Polygon.
As I know, to open/create new instance of dialog, somehow Service must notify controller to do that.
This is a template with controller + method and service: Template
var myApp = angular.module('myApp', []);
function MyCtrl($scope, gridService, $timeout) {
// how to call "foo" method from service?
$scope.foo = function(){
alert('called from service');
};
}
myApp.service('gridService', ['$timeout', function ( $timeout) {
var grid = {
fetching: false,
pristine: true,
pageType: 'Edit'
}
return {
gridSetup: function () {
return grid;
},
setGridSetup: function (newGrid) {
}
}
}]);
Thanks,
The answer is simple: you don't.
The service exists to manipulate data, nothing else. And it really shouldn't care "why" it's doing what it's doing. You ask the service to do something and wait for a response.
Personally I prefer using promises to resolve async operations (i.e. to notify the controller about a state change) since it's heavily supported by many angular services like $http.
But feel free to use callbacks of you wish.
Usually you do not need to call controller from the service - in general the single service could be used by any controller so service shall know nothing about them. In most cases controller calls to the service in react to some user's action and then you need to update view from controller somehow when service did its work (get response from server, etc.). I see following general ways how to do it.
1. Use callbacks.
//controller
$scope.onButtonClick = function() {
$scope.label = "wait, loading...";
function onSuccess(result) {
$scope.label = "done! result is " + result;
}
myService.doSomeWork(param1, param2, onSuccess);
}
//service
doSomeWork: function(param1, param2, onSuccess) {
$.get({...}, onSuccess);
}
So you provide a callback for each action.
2. Subscribe on events
You may use jQuery for events subscribing/triggering
//controller
$(myService).on('update', function() {
$scope.lastUpdateTime = new Date();
});
$scope.onButtonClick = function() {
myService.doUpdate();
}
//service
doUpdate: function() {
$.get({...}, function onOk() {
$(this).trigger('update');
});
}
3. Use promises
A lot of built-in angular services return promise objects, you may use them too:
//controller
myService.doSomething(param1).then(function(result) {
$scope.result = result;
});
//service
doSomething: function(param1) {
return $http.get({...});
}
4. Share some data
An example is $resource service - for example when you call query method it returns empty array-like object that could be safely put to scope and then fills it with values when http request is done.
//controller
$scope.options = myService.options;
$scope.onClick = function() { myService.update() }
//service
options: [],
update: function() {
var self = this;
$http.get({...}).success(function(res) {
self.options.splice(0, self.options.length); //to keep same array
self.options.push.apply(self.options, res.data.options);
});
}
In all these cases services and controllers are separated, services could be used with any controller and you may easily write unit-tests on services that will not break if you change your controller/view part somehow.
A possible solution would be to have a dialog service which you can inject into the grid service. So when the user right clicks on the polygon the handler would call open on the dialog service.
Take a look at the modal service on angular ui as an example.

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