I've started testing my Angular app and have question that bother me a lot. For example I have controller (mainController) which is injecting 2 services: authService, configService.
Before testing I should prepare something like that:
describe('controller: testController with testService mock', function() {
var controller, authService, configService;
beforeEach(module('app'));
beforeEach(inject(function($controller, _authService_, _configService_) {
authService = _authService_;
configService = _configService_;
controller = $controller('mainController');
}));
it('should be registered with all dependencies', function() {
expect(controller).to.be.defined;
expect(authService).to.be.defined;
expect(configService).to.be.defined;
});
}
And that's totally clear for me. What if one of services or both have their own dependencies (services) ? Of course I'm gonna add it by passing through the inject function. In small apps that's no big problem. I'm adding as much services as I need. But the question is what if that services are injecting other services and others injecting others and there is a huge hierarchy ? What if we must add 30 services and we can't make a mistake because otherwise it's not gonna work ?
To be honest I've search a lot but there are many testing examples and tutorials but every single one is based on totally basic apps with few controllers and services.
Is there a painless way to handle this ? Maybe there is a way to skip some dependencies or force to automatically inject services with it's dependencies ?
What if one of services or both have their own dependencies (services) ? Of course I'm gonna add it by passing through the inject function
No, you won't. Angular will instantiate these services and inject them where they need to be injected, provided they're in the 'app' module or in one of its dependencies.
There's no reason to inject any service into your test, unless you need to do something with them, like calling one of their methods, or spying them.
Related
My app is following John Papa's styleguide for AngularJS applications:
The styleguide emphasizes using a strongly modular approach to the design of the app. My question is about multiple configurations and their effect on shared services.
Suppose I have a main module like this:
angular.module("app", ["app.feature1"])
.config(function() {
// do some configuration here
console.log("app configured");
});
And a feature module that configures a shared angular service, let's say the $http service:
angular.module("app.feature1", [])
.config(function($http) {
// configure the $http service
console.log("feature1 configured");
});
Is my understanding correct, that the configuration by "feature1" will carry over to the main module, since the $http service is a singleton and therefore shared across modules? Or do I have to configure the $http service in the main module instead, because each module has it's own $http service instance?
Edit: I can confirm that dependency configs are carried over and are executed first. See David's jsfiddle example.
As a matter of best practice, you should configure services as early as possible, which is typically your main module (the app root), and preferably only once to avoid overlapping changes.
Since $http is a singleton (as you mentioned), any changes via configuration will be propagated throughout the application every time you inject $http.
It's also worth mentioning that configuration to services is First In First Out, meaning that if you have two configuration changes, the last-accessed configuration will be the one that is persisted to the service since the previous configuration will be overwritten if they are changing identical components of the service.
In your case, yes, the change to $http in your module will be extended to your main application and any other modules using $http.
Finally, in light of the comments, child dependency configs are resolved before parent configs, as demonstrated by this simple fiddle:
http://jsfiddle.net/maqzo6fv/
HTML:
<div ng-app="app"></div>
JS:
angular.module("app", ["app.feature1"])
.config(function() {
alert('main config');
});
angular.module("app.feature1", [])
.config(function() {
alert('child config');
});
The child config will call alert before main on every load.
Code ...
angular.module('appName').factory('serviceName', ['$http', function ($http) {
Here, I am making Angular's $http service available to my service but how do I make it available to all services in my app without having to define it every time in every service within the app (assuming every service in my app needs access to $http)?
Please could code samples be provided. Many thanks in advance
There seems to be very little help on this issue.
angular.module('appName').factory('globalize', ['$http', function ($http) {
window.$http = $http;
}]);
e.g
http://plnkr.co/edit/HbyX2Bx8c3TNJyvL2ljf?p=preview
there you go, it's global now. But this is not the best thing to do...
Anyone know the best recommended way of creating models in a separate JavaScript file and have these injected into the controllers that need them, rather than creating the models on fly normally in the controller?
This would make it so much easier to pass around the model and you would know exactly what you was passing around.
I have some thoughts on using Services, and inject these where I need i.e. controllers.
Controllers would then pass these onto specific services to do any heavy lifting to keep my controllers nice and light.
Is services the only and recommended way to go ? Or is there a better alternative way ?
Any use of third-party libraries / modules would also be considered.
I think services are the way to go. Not only are they injectable but they are also Singletons - meaning wherever they are injected, the same instance is shared.
Example of a service which uses the $http service to make an asynchronous call to retrieve data:
app.factory('customerService', function($http) {
var customers = [];
$http({ url: 'api/customers/all', method:'GET'}).success(function(data) {
angular.copy(data, customers);
});
return {
customers: customers
};
});
In your controller or directive, you can then inject the service and bind customers to your scope:
app.controller('ctrl', function($scope, customerService) {
$scope.customers = customerService.customers;
});
The best way to do it is by service for couple of reasons.
If you use ng-view and routing the service is not reloading and your data is safe in service
It's easy injectable to controllers
Provides two-way data binding between controllers
working plunker with two-way data binding between controllers
http://plnkr.co/edit/pt2xwlYqvY3r840tHJ92?p=preview
NOTE: if you don't have a dot in your model you are doing something wrong ;)
I believe services are the best way for this.
I have used scope inheritance to place some methods that most of my app would need at once such as a routing method I attached these to the .run () method of my main module/app.
You could separate your models into separate modules if you needed to structure your app that way.
I am building a web application with AngularJS and have built out a AngularJS Service that my controller uses to create, retrieve, update, delete data from. I want to farm out the UI work to another developer, but I don't want them to require the dependencies that the AngularJS Service does. I'd like to build a Mock Service and just return mock data rather than call the live REST service.
My App is set up like this:
var myApp = angular.module('myApp', ['ui.bootstrap']);
My Controller currently hooks up to the Service using:
myApp.controller('TodoCtrl', function TodoCtrl($scope, $JSOMService) {
$JSOMService.DoStuff();
});
And my Service is defined like this
myApp.service('$JSOMService', function ($q, $http) { ... });
What the are best ways to handle switching out the service for another one? This is a little different from Unit Testing and I wondered if there are any common ways of doing this?
For now I'm just having a slightly different code base where I just switch out the Angularjs Service javascript files loaded to handle this.
You can get access directly to the provider service, which controls injections. It would look something like this, where $provide is injected:
$provide.value('$JSOMService', MockJSOMService());
This will basically say, whenever someone asks for $JSOMService, give them whatever was returned from MockJSOMService.
You can set this up at the when you set up your app. Like this:
myApp.run(['$provide', function($provide) {
$provide.value('$JSOMService', MockJSOMService());
}]);
This is basically how you could switch out services. Admittedly a little funky, but I hope this helps!
In our app, we are making cross domain requests, and so we have to use CORS. Since IE does this in a non-standard way, we created our own service (which has a dependency on $http for non-IE requests) that would handle all this for us. This all works fine within this app. However we have some non-app specific library code that needs to make requests. So, if these services in our library code simply use $http, the requests would not work in the app that needs to do CORS. However, we don't want these services injecting our CORS service, because that would break requests in apps that aren't doing cross-domain requests.
With all that being said, my end goal is to have the library code inject and use $http for all necessary requests. Then, in the specific apps, it could define how $http works. I initially thought I could just redefine the provider for $http. Something like this:
angular.module("myCorsApp").provider("$http", function() {
return {
$get: function(CORShttpService) {
return CORShttpService;
}
}
});
However, this results in the following error:
Circular dependency: CORShttpService <- $http <- $compile
I'm not sure I understand where the circular dependency is coming from. Does $compile have a dependency on the providers or something?
My real question is if I'm even going about this the right way. If there wasn't the circular dependency, I would think this would accomplish exactly what I want. Is there some workaround I can do to make this work? Is there a better/more correct way of doing this?
If it helps at all, the CORShttpService has the following dependencies: $q, $rootScope, $http, $timeout. Thanks for any help.
After digging around a bunch in the Angular docs, I decided that the best approach here was to "decorate" the $http service. This done with the decorator function of the $provide service. So, I ended up with something like this:
angular.module("myCorsApp").config(function($provide) {
$provide.decorator("$http", ["$delegate", "$q", "$rootScope", "$timeout", function($http, $q, $rootScope, $timeout) {
return function(requestConfig) {
//CORS logic using $http (basically what was the CORShttpService)
}
}]);
});