How to create / instantiate AngularJs controllers on the fly? - javascript

I have a simple controller that works just fine:
app.controller('IndexController', ['$scope', obj.indexPage]);
var obj = {};
obj.indexPage = function ($scope) { // do controller stuff };
I also have an event function that i want to use to load/create/instantiate this controller:
// some callback, doesn't really matter
app.onPage('index', function () {
// load and run controller logic in here
app.controller('IndexController', ['$scope', obj.indexPage]);
}, obj);
there are some issues, like Argument 'IndexController' is not a function, got undefined
Any ideas?
my solution:
app.controller('IndexController', ['$scope', function ($scope) {
var obj = {};
obj.indexPage = function (data) {
// do controller stuff
};
app.onPage('index', function (data) {
obj.indexPage(data);
}, obj);
});

Due to how the angular module system works, you can't instantiate controllers asynchronously like that. You can however, use the $controller service to create controllers on the fly. The same technique below is often used in unit testing.
For example:
angular.module('app', [])
.controller('MyCtrl', function($rootScope, CtrlFactory){
var dynamicCtrl = CtrlFactory.create({$scope: $rootScope.$new()});
console.log(dynamicCtrl.method()); //-> 123
})
.factory('CtrlFactory', function($controller) {
return {
create: function(locals) {
return $controller(
//this is the constructor of the new controller
function($scope){
console.log('Dynamic controller', $scope);
this.method = function() { return 123; };
},
//these are the injected deps
locals
);
}
};
})
For some example usage in a unit testing context, see: https://docs.angularjs.org/guide/controller.
I'll add that you may want to reconsider your reasons for doing this--I can't say I've seen $controller used outside testing.

app.onPage('index', function () {
app.controller('IndexController', obj.indexPage); // this would load the controller to the module
$controller('IndexController', { $scope: $scope }); // This would instantiate the controller, NOTE: $controller service should be injected
}, obj);

Related

Angular Jasmine UI router inject resolve value into test

In my Angular app, UI router resolves a promise into the controller. When trying to test this controller, Karma is complaining about an unknown provider. How do I inject a fake object into the test to represent this resolve object.
My app's code looks something like:
angular.module('myapp')
.config(function($stateProvider, $urlRouterProvider) {
$stateProvider
.state('tab.name', {
...
resolve: {
allTemplates: function(Templates) {
return Templates.all().then(function(templates) {
return templates;
});
}
}
})
})
.controller('QueriesCtrl', function(allTemplates, UserQuery) {
var vm = this;
vm.queries = allTemplates;
vm.goToUrl = function(index, data) {
var processedUrl = UserQuery.process(data, vm.queryTyped[index]);
UserQuery.goToUrl(processedUrl);
};
});
When trying to run tests I get the error
Unknown provider: allTemplatesProvider <- allTemplates <- QueriesCtrl
I've tried creating a spy and injecting it, but this does not work. Here's my test at the moment:
describe('Unit: queriesCtrl', function() {
var controller,
scope,
UserQuery;
beforeEach(function() {
module('myapp');
inject(function($injector) {
UserQuery = $injector.get('UserQuery');
allTemplates = jasmine.createSpyObj('allTemplates', [{a:1}, {a:2}, {b:3}]);
});
});
describe('goToUrl', function() {
beforeEach(inject(function ($rootScope, $controller) {
scope = $rootScope.$new();
controller = $controller('QueriesCtrl as ctrl', {
'$scope': scope
});
}));
it('should call UserQuery.process()', function() {
spyOn(UserQuery, 'process');
scope.ctrl.goToUrl();
expect(UserQuery.process).toHaveBeenCalled();
});
});
});
Since there is no route involved in unit test you would have to inject the allTemplates as a normal object with $controller function. Can you try:
controller = $controller('QueriesCtrl as ctrl', {
'$scope': scope,
'allTemplates':allTemplates
});
Else you can use the $provide API to create a dummy service.
module(function ($provide) {
$provide.value("allTemplates", {[{a:1}, {a:2}, {b:3}]});
Do it first thing in your beforEach block.

Unit testing angular/Ionic project

I have a very simple controller that looks like this.
timeInOut.controller('timeInOutController', function($scope, $filter, $ionicScrollDelegate){
...
});
Whenever I try to create a unit test for it like so...
(function() {
'use strict';
var scope, controller, filter;
describe('timeInOutController', function () {
beforeEach(module('common.directives.kmDateToday'));
beforeEach(inject(function ($rootScope, $controller, $filter) {
scope = $rootScope.$new();
filter = $filter;
controller = $controller('timeInOutController', {
$scope: scope
});
}));
describe('#date setting', function(){
...
});
});
})();
I get the error:
[$injector:unpr] Unknown provider: $ionicScrollDelegateProvider <- $ionicScrollDelegate
Obviously in my example here I'm not trying to inject the $ionicScrollDelegate into the test, that's just because I've tried it any number of ways with no success and don't know which failed attempt to include.
Also in my karma.conf.js file I am including the ionic.bundle.js and angular-mocks.js libraries/files.
I can successfully unit test anything that doesn't use anything $ionic in it, so I know my testing framework is set up correctly, the issue is injecting anything ionic related.
You need to pass in all the parameters if you're going to instantiate your controller via angular. By adding the parameters you are telling angular that any time you create one of these controllers I need these things too because I am dependent upon them.
So my suggestion is to mock up some representation of these dependencies and inject them in when you are creating the controller. They do not have to be (and should not be) the actual services for your unit tests. Jasmine gives you the ability to create spy objects that you can inject so you can verify the the behavior of this unit.
(function() {
'use strict';
var scope, controller, filter, ionicScrollDelegate;
describe('timeInOutController', function () {
beforeEach(module('common.directives.kmDateToday'));
beforeEach(inject(function ($rootScope, $controller, $filter) {
scope = $rootScope.$new();
filter = $filter;
// func1 and func2 are functions that will be created as spies on ionicScrollDelegate
ionicScrollDelegate = jasmine.createSpyObj('ionicScrollDelegate', ['func1', 'func2']
controller = $controller('timeInOutController', {
$scope: scope,
$filter: filter,
$ionicScrollDelegate: ionicScrollDelegate
});
}));
describe('#date setting', function(){
...
});
});
})();
You can find more about spies via jasmine's documentation
You need to create mock objects for all dependencies your controller is using.
Take this controller as an example:
angular.module('app.module', [])
.controller('Ctrl', function($scope, $ionicLoading) {
$ionicLoading.show();
});
Here you are using the $ionicLoading service, so if you want to test this controller, you have to mock that object specifying the methods you're using in the controller:
describe('Test', function() {
// Mocks
var $scope, ionicLoadingMock;
var ctrl;
beforeEach(module('app.module'));
beforeEach(function() {
// Create $ionicLoading mock with `show` method
ionicLoadingMock = jasmine.createSpyObj('ionicLoading', ['show']);
inject(function($rootScope, $controller) {
$scope = $rootScope.$new();
ctrl = $controller('Ctrl', {
$scope: $scope,
$ionicLoading: ionicLoadingMock
});
});
});
// Your test goes here
it('should init controller for testing', function() {
expect(true).toBe(true);
});
});

update angular model from a service

angular.module('app.services', []).service("test", function($http, $rootScope){
this.test=function(){
$rootScope.name="test1";
};
};
angular.module('app.controllers', []).controller('TestController', function ($scope, test) {
test.send();
})
I dont get an error but the changes don't get applied to the UI. I tried $scope.apply() and got an error.
We need to tell Angular which modules your module depends on, In our case the main module is app.controllers.
To call service from different model we need tell to controller where is our service:
['app.services']
JS
var appServices = angular.module('app.services', []);
var appCtrl = angular.module('app.controllers', ['app.services']);
appServices
.service("test", function ($http, $rootScope) {
this.send = function () {
$rootScope.name = "test1";
};
});
appCtrl.controller('TestController', function ($scope, test) {
test.send();
});
Demo Fiddle
I think you should change ".service" by ".factory".
As I can see in the creating services docs there are 3 ways of creating custom services. One of then is using factory way, as the following:
var myModule = angular.module('myModule', []);
myModule.factory('serviceId', function() {
var shinyNewServiceInstance;
//factory function body that constructs shinyNewServiceInstance
return shinyNewServiceInstance;
});
Hope to help.

How do I mock the result in a $http.get promise when testing my AngularJS controller?

After much reading, it seems that the recommended way to call a web service from an AngularJS controller is to use a factory and return a promise from that.
Here I have a simple factory which calls a sample API.
myApp.factory('MyFactory', ['$http',function($http) {
var people = {
requestPeople: function(x) {
var url = 'js/test.json';
return $http.get(url);
}
};
return people;
}]);
And this is how I call it in the controller
myApp.controller('MyCtrl1', ['$scope', 'MyFactory', function ($scope, MyFactory) {
MyFactory.requestPeople(22).then(function(result) {
$scope.peopleList = result;
});
}]);
While it works fine, I would like to be able to mock the result that is passed in when then is called. Is this possible?
My attempt so far has produced nothing. This is my attempt:
//Fake service
var mockService = {
requestPeople: function () {
return {
then: function () {
return {"one":"three"};
}
}
}
};
//Some setup
beforeEach(module('myApp.controllers'));
var ctrl, scope;
beforeEach(inject(function ($rootScope, $controller) {
scope = $rootScope.$new();
ctrl = $controller('MyCtrl1', { $scope: scope, MyFactory: mockService });
}));
//Test
it('Event Types Empty should default to false', inject(function () {
expect(scope.peopleList.one).toBe('three');
}));
The error that I get when running this in karma runner, is
TypeError: 'undefined' is not an object (evaluating 'scope.peopleList.one')
How can I get this test working with my mocked data?
I don't think $httpBackend is what you're after here, you want the whole factory to be mocked without it having a dependency on $http?
Take a look at $q, in particular the code sample under the Testing header. Your issue might be resolved with code that looks like this:
'use strict';
describe('mocking the factory response', function () {
beforeEach(module('myApp.controllers'));
var scope, fakeFactory, controller, q, deferred;
//Prepare the fake factory
beforeEach(function () {
fakeFactory = {
requestPeople: function () {
deferred = q.defer();
// Place the fake return object here
deferred.resolve({ "one": "three" });
return deferred.promise;
}
};
spyOn(fakeFactory, 'requestPeople').andCallThrough();
});
//Inject fake factory into controller
beforeEach(inject(function ($rootScope, $controller, $q) {
scope = $rootScope.$new();
q = $q;
controller = $controller('MyCtrl1', { $scope: scope, MyFactory: fakeFactory });
}));
it('The peopleList object is not defined yet', function () {
// Before $apply is called the promise hasn't resolved
expect(scope.peopleList).not.toBeDefined();
});
it('Applying the scope causes it to be defined', function () {
// This propagates the changes to the models
// This happens itself when you're on a web page, but not in a unit test framework
scope.$apply();
expect(scope.peopleList).toBeDefined();
});
it('Ensure that the method was invoked', function () {
scope.$apply();
expect(fakeFactory.requestPeople).toHaveBeenCalled();
});
it('Check the value returned', function () {
scope.$apply();
expect(scope.peopleList).toBe({ "one": "three" });
});
});
I've added some tests around what $apply does, I didn't know that until I started playing with this!
Gog

What's the recommended way to extend AngularJS controllers?

I have three controllers that are quite similar. I want to have a controller which these three extend and share its functions.
Perhaps you don't extend a controller but it is possible to extend a controller or make a single controller a mixin of multiple controllers.
module.controller('CtrlImplAdvanced', ['$scope', '$controller', function ($scope, $controller) {
// Initialize the super class and extend it.
angular.extend(this, $controller('CtrlImpl', {$scope: $scope}));
… Additional extensions to create a mixin.
}]);
When the parent controller is created the logic contained within it is also executed.
See $controller() for for more information about but only the $scope value needs to be passed. All other values will be injected normally.
#mwarren, your concern is taken care of auto-magically by Angular dependency injection. All you need is to inject $scope, although you could override the other injected values if desired.
Take the following example:
(function(angular) {
var module = angular.module('stackoverflow.example',[]);
module.controller('simpleController', function($scope, $document) {
this.getOrigin = function() {
return $document[0].location.origin;
};
});
module.controller('complexController', function($scope, $controller) {
angular.extend(this, $controller('simpleController', {$scope: $scope}));
});
})(angular);
<script src="https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.3.15/angular.js"></script>
<div ng-app="stackoverflow.example">
<div ng-controller="complexController as C">
<span><b>Origin from Controller:</b> {{C.getOrigin()}}</span>
</div>
</div>
Although $document is not passed into 'simpleController' when it is created by 'complexController' $document is injected for us.
For inheritance you can use standard JavaScript inheritance patterns.
Here is a demo which uses $injector
function Parent($scope) {
$scope.name = 'Human';
$scope.clickParent = function() {
$scope.name = 'Clicked from base controller';
}
}
function Child($scope, $injector) {
$injector.invoke(Parent, this, {$scope: $scope});
$scope.name = 'Human Child';
$scope.clickChild = function(){
$scope.clickParent();
}
}
Child.prototype = Object.create(Parent.prototype);
In case you use the controllerAs syntax (which I highly recommend), it is even easier to use the classical inheritance pattern:
function BaseCtrl() {
this.name = 'foobar';
}
BaseCtrl.prototype.parentMethod = function () {
//body
};
function ChildCtrl() {
BaseCtrl.call(this);
this.name = 'baz';
}
ChildCtrl.prototype = Object.create(BaseCtrl.prototype);
ChildCtrl.prototype.childMethod = function () {
this.parentMethod();
//body
};
app.controller('BaseCtrl', BaseCtrl);
app.controller('ChildCtrl', ChildCtrl);
Another way could be to create just "abstract" constructor function which will be your base controller:
function BaseController() {
this.click = function () {
//some actions here
};
}
module.controller('ChildCtrl', ['$scope', function ($scope) {
BaseController.call($scope);
$scope.anotherClick = function () {
//other actions
};
}]);
Blog post on this topic
Well, I'm not exactly sure what you want to achieve, but usually Services are the way to go.
You can also use the Scope inheritance characteristics of Angular to share code between controllers:
<body ng-controller="ParentCtrl">
<div ng-controller="FirstChildCtrl"></div>
<div ng-controller="SecondChildCtrl"></div>
</body>
function ParentCtrl($scope) {
$scope.fx = function() {
alert("Hello World");
});
}
function FirstChildCtrl($scope) {
// $scope.fx() is available here
}
function SecondChildCtrl($scope) {
// $scope.fx() is available here
}
You don't extend controllers. If they perform the same basic functions then those functions need to be moved to a service. That service can be injected into your controllers.
Yet another good solution taken from this article:
// base controller containing common functions for add/edit controllers
module.controller('Diary.BaseAddEditController', function ($scope, SomeService) {
$scope.diaryEntry = {};
$scope.saveDiaryEntry = function () {
SomeService.SaveDiaryEntry($scope.diaryEntry);
};
// add any other shared functionality here.
}])
module.controller('Diary.AddDiaryController', function ($scope, $controller) {
// instantiate base controller
$controller('Diary.BaseAddEditController', { $scope: $scope });
}])
module.controller('Diary.EditDiaryController', function ($scope, $routeParams, DiaryService, $controller) {
// instantiate base controller
$controller('Diary.BaseAddEditController', { $scope: $scope });
DiaryService.GetDiaryEntry($routeParams.id).success(function (data) {
$scope.diaryEntry = data;
});
}]);
You can create a service and inherit its behaviour in any controller just by injecting it.
app.service("reusableCode", function() {
var reusableCode = {};
reusableCode.commonMethod = function() {
alert('Hello, World!');
};
return reusableCode;
});
Then in your controller that you want to extend from the above reusableCode service:
app.controller('MainCtrl', function($scope, reusableCode) {
angular.extend($scope, reusableCode);
// now you can access all the properties of reusableCode in this $scope
$scope.commonMethod()
});
DEMO PLUNKER: http://plnkr.co/edit/EQtj6I0X08xprE8D0n5b?p=preview
You can try something like this (have not tested):
function baseController(callback){
return function($scope){
$scope.baseMethod = function(){
console.log('base method');
}
callback.apply(this, arguments);
}
}
app.controller('childController', baseController(function(){
}));
You can extend with a services, factories or providers. they are the same but with different degree of flexibility.
here an example using factory : http://jsfiddle.net/aaaflyvw/6KVtj/2/
angular.module('myApp',[])
.factory('myFactory', function() {
var myFactory = {
save: function () {
// saving ...
},
store: function () {
// storing ...
}
};
return myFactory;
})
.controller('myController', function($scope, myFactory) {
$scope.myFactory = myFactory;
myFactory.save(); // here you can use the save function
});
And here you can use the store function also:
<div ng-controller="myController">
<input ng-blur="myFactory.store()" />
</div>
You can directly use $controller('ParentController', {$scope:$scope})
Example
module.controller('Parent', ['$scope', function ($scope) {
//code
}])
module.controller('CtrlImplAdvanced', ['$scope', '$controller', function ($scope, $controller) {
//extend parent controller
$controller('CtrlImpl', {$scope: $scope});
}]);
You can use Angular "as" syntax combined with plain JavaScript inheritance
See more details here
http://blogs.microsoft.co.il/oric/2015/01/01/base-controller-angularjs/
I wrote a function to do this:
function extendController(baseController, extension) {
return [
'$scope', '$injector',
function($scope, $injector) {
$injector.invoke(baseController, this, { $scope: $scope });
$injector.invoke(extension, this, { $scope: $scope });
}
]
}
You can use it like this:
function() {
var BaseController = [
'$scope', '$http', // etc.
function($scope, $http, // etc.
$scope.myFunction = function() {
//
}
// etc.
}
];
app.controller('myController',
extendController(BaseController,
['$scope', '$filter', // etc.
function($scope, $filter /* etc. */)
$scope.myOtherFunction = function() {
//
}
// etc.
}]
)
);
}();
Pros:
You don't have to register the base controller.
None of the controllers need to know about the $controller or $injector services.
It works well with angular's array injection syntax - which is essential if your javascript is going to be minified.
You can easily add extra injectable services to the base controller, without also having to remember to add them to, and pass them through from, all of your child controllers.
Cons:
The base controller has to be defined as a variable, which risks polluting the global scope. I've avoided this in my usage example by wrapping everything in an anonymous self-executing function, but this does mean that all of the child controllers have to be declared in the same file.
This pattern works well for controllers which are instantiated directly from your html, but isn't so good for controllers that you create from your code via the $controller() service, because it's dependence on the injector prevents you from directly injecting extra, non-service parameters from your calling code.
I consider extending controllers as bad-practice. Rather put your shared logic into a service. Extended objects in javascript tend to get rather complex. If you want to use inheritance, I would recommend typescript. Still, thin controllers are better way to go in my point of view.

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