When creating integration tests for my Ember components I can pick up fired actions (aka, with on handler) and text properties set in the DOM (aka, with $(target).text().trim()). I can even pass in a bound value and watch it's value change so long as it's a two-way binding (aka, {{my-comp value=value}}). But what I often want to do is observe a property within the component without binding to it. With a unit test this would be easy but unit tests are quite awkward in many ways so I'm trying to accomplish most my testing needs in integration tests these days.
Any help would be greatly appreciated.
p.s. the Ember Inspector seems to indicate that what I'm trying to achieve is definitely possible
Related
In Ember.js, I currently want to test a UI feature present. Essentially, once a model variable changes, I expect to see a UI element appear (a checkmark). I have tried creating a model within the acceptance test but this unfortunately did not work as I did.
I just wanted to know which function to use to set model variables.
A model typically would involve unit tests, but like you've said you're testing the visual result of something being set on a model. I would recommend an integration test. If you are able to refactor (or maybe this is the case already), the part of the template into a component then you can create an ember test for the component and pass in the model set up perfectly how you would like.
If this test really does depend on the model being setup a specific way I would look at how your application sets up that model to begin with and try to replicate those actions with click and fillIn helpers. Another way is say, your application wants to setup a user but relies on a network request to do this, then you could use pretender.js and fake the response to that request so that the application's inputs are setup from the network in the way you're after.
I would really try to do this an acceptance test though, the composable nature of components allows them to be tested in stricter isolation, these tests will run faster, and you're worrying less about side effects.
I want to use (some of) my own ember components in a nested way. Think
{{#form-helper data=model}}
{{form-field datakey="name"}}
{{form-field datakey="street}}
{{form-field datakey="city}}
{{/form-helper}}
Generalized: I've got two components that are meant to work together in a nested way. The outer one provides some environment that is consumed by the inner one. http://alexspeller.com/simple-forms-with-ember/ has this explained in some more detail and uses the inner components parentView to access the outer context. Great.
Now, ember components are meant to fill in for web components as long as they aren't ready for prime time, but from what I understand web components are meant to be encapsulated. The only way to exchange information are data binding and events.
If this is correct and ember strives to replace its own components with web components, would this solution be future proof. Can I rely on ember delivering some kind of parentView access after the switch to real web components?
If not, what would be the right, the ember way to do this? A component outside and view helpers inside? Some usage of binding and events that I am currently unaware of?
I know I've got a solution for now, but I'm developing a solution that will be in use for quite a long time, so I want to avoid anything that's essentially deprecated at the time of writing my code.
So I've created an require.js and backbone.js (actually marionette.js) application that basically is some sort of mobile app builder.
Now I want to create tests for it, basically testing this scenario:
Navigate to an existing project, e.g site.com/build/1234
Drag a component, check if it is added correctly.
Change properties of a component and see if they are updated correctly. I.e: I've a properties panel which lists the properties
of the selected component, than for example I've a property which
is a selectmenu and changes the size (small, medium, large). I
should be able to test this.
Now I've been searching on google, however since there are so many testing frameworks, i'm not sure which one to pick and which one provides the functionalities I need.
Potentially PhantomJS seems to be something I could use, however please advice me with some specific information.
Thanks.
if you want to actually simulate clicks, look into selenium (http://docs.seleniumhq.org/projects/webdriver/)
If you just want to test that your Backbone components(views, controllers, etc) and templates are working correctly, you can use a js test runner such as Karma (http://karma-runner.github.io/0.12/index.html) to run your tests. Sinon can mock out your ajax calls for you as well. It can use PhantomJs as a rendering engine, so you can actually render your views, and use view.$() style DOM inspection to verify the output of your views.
I seem to be getting more and more confounded at what appears, on the surface at least to be pretty basic architectural questions regarding building ember apps.
Which Controller type?
In the last month or so, I've seen people implement controllers through Ember.Controller, Ember.ArrayController, Ember.ObjectController, and Ember.ArrayProxy. Removing ArrayController and ArrayProxy (due to them being identical), what are common use cases between each type?
So far, i've been able to gather that:
ArrayControllers/Proxies should be used when you have n elements within the view you intend to control
ObjectControllers should be used when the view is simple enough to maintain it's state in a single object, or be a single instance of a model's object.
Controllers --- ? No idea.
What are some basic differences between the controller types? There doesn't seem to be concrete information on when to use which, and for which use case. The API docs are good at telling me the nitty gritty of each of them, but not WHEN to use each.
The relationship between a View and a Controller can be baffling
When a View is connected via a routes ConnectOutlets function call, what exactly happens between the controller and the view?
Are events tied into the view itself (which seems to be the case) and if so, where on earth do you interact with the controller singleton to perform CRUD-esq things on its properties? this.get('controllerName') doesn't seem to do the trick, and nearly each post or tutorial or code sample out there does this a different way.
Models that aren't
I realize that Ember Data looks to help solve some of the more irritating parts of dealing with data and keeping it in sync, but at a larger perspective, in the concept of "MVC", ember doesn't really seem to have a Model of any kind. It's just some object that gets subclassed from a specific thing and then tracked....somewhere? Somehow? Magical?
#trek sufficed that an Ember.Object could manage ajax'ing data and handling state on the client just fine, but if you look at something like the todomvc.com ember app, it uses a localStorage paradigm that is COMPLETELY different in implementation then everything i've looked at.
How EXACTLY should the 'Model' part of the MVC equation be done here?
Views make me want to murder children
There seems to be a significant number of ways to construct a "view" in terms of displaying markup to a user.
ContainerViews, using subviews / childviews
nested outlets
Handlebars templates + an outlet
using #each foo in controller
Injection through literals (template: Ember.Handlebars.compile('<h1>foo</h1>') etc)
With that in mind, what's the 'proper' way to build modular UI components with ember? This more than anything is a major pain point for the adoption of this framework for me.
I love the direction that Ember is going with application development on the web. The concepts seem simple, but the verbosity is that of Objective-C (which makes sense given it's lineage) but I swear to god I feel like i'm fighting the god damned framework more than i'm actually working on my application. The verbosity of the syntax and the lack of structured documentation outside of API documentation (which lets face it, 300k of javascript is a significant amount of code to throw some breakpoints down and try to debug your issues).
I realize the challenge that you guys are up against, but hopefully this at least makes you pause for a minute and think of how you could make life easier for the incoming developer who's worked with other frameworks (or hell, even worked within an MVC framework, like rails or django or backbone or angular) and say "this is how we think ember should be used".
Take some of the opinionated software design decisions and apply them toward the community. We'll do nothing but be cheerleaders for you if you do it, promise.
Please don't hurt any children. AFAIK the ember-core team are all over 18, so any ember-view-related frustration is clearly better directed towards adults. With that in mind...
Which Controller Type?
You've got the "what" right, but maybe missing the "why". Controller can be a little misleading, especially coming from rails. Think of these controller singletons as representing the state (in-memory) of your application.
Which kind of controller to use depends on what is required for that part of your application. For example, a back-of-napkin sketch for any app might have a topnav, postList, postDetails section. In ember, each is represented by one or more view/controller pairs. In this app I would expect to see ApplicationController and NavigationController extending Ember.Controler while postList would extend ArrayController and PostDetails would be an ObjectController.
You could do it all using just Ember.Controller but ObjectController and ArrayController are really useful for wrapping model data. Any non-trivial ember app will probably use all three.
The relationship between a View and a Controller
A controller's job is to provide the context in which the view will be rendered. Ideally you'd like to keep logic out of views, so a typical controller will have lots of computed properties to do things like:
transform data from the underlying model objects
sort/filter/select a list of objects
reflect application state
whats the deal with connectOutlets? This is where you should be using the requested route/context to decide which views/data should be plugged into the outlets of your application. The controller's connectOutlet method has a bunch of magic to make it easy, but maybe too much magic. What happens (afaik) when you call: parentcontroller.connectOutlet 'child' is
Ember creates an instance of ChildView
The {{outlet}} handlebars helper in parentController's view is bound to this childView instance
The childView is rendered with the router.childController singleton as it's context
where to do crud stuff?: Typically in an action on the router. This seems crazy at first. Think of ember router not like rails but as a stateManager that just happens to also handle routing. In near-future router API will change to make this more clear. Anyway, use router actions to do things like create model instances, commit/rollback transactions and trigger state change. This is easy to do if you use the handlebars {{action}} helper for links/buttons as it targets the router by default.
Views on the other hand should have logic for "reacting to browser events" - that means really low-level stuff like show/hide something on mouseover or integrate with 3rd party libraries to do effects and animations.
You might find this screencast helpful in understanding how to do CRUD-esq things:
http://blog.bigbinary.com/2012/09/06/crud-application-in-emberjs.html
Models WTF?
Agreed in Ember any object could be used as a 'Model'. I think #trek does a good job of demonstrating how one might accomplish this via Ember.Object. This works great for a simple app, and six months back maybe would've been your best bet as ember-data was really immature. I'm not clear on the history of ember's todomvc app, but for sure it was written months ago. For sure it should be updated, but meantime I'd not recommend using it to learn about current ember best-practices.
Instead, you should go with ember-data. Over the last few months it has really evolved and should be the default choice for any new, non-trivial ember app. #tomdale just gave a great presentation on this topic, I'd recommend having a look: https://speakerdeck.com/tomdale/ember-data-internals
what's the 'proper' way to build modular UI components with ember?
For building modular UI components:
ContainerViews, using subviews / childviews
Injection through literals (template: Ember.Handlebars.compile ...)
For building an individual application:
nested outlets
Handlebars templates + an outlet
using #each foo in controller
Building modular UI components is a totally different problem than building an application. Ember.View and it's subclasses were designed for this purpose. You can easily extend/combine them to compose widgets with custom behaviors and share those widgets across applications.
At least that's how i've seen it done. If they are for internal use could also reference handlebars templates instead of object literals, but if planning to distribute the object literals approach seems best.
A great real-world example of this is the ember-bootstrap project. I learned a lot about working with ember-views by reading through that project's source. http://emberjs-addons.github.com/ember-bootstrap/
TLDR
Pick controller that maps to type of data being represented
Controllers provide context for the view and remember application state
Use ember data for your models
Use subclasses of Ember.View to make components
Be nice to children
I've found absolutely nothing on Google with regard to A/B testing with a client-side framework such as ember.js.
The goal is to serve up adjusted content (different nav items, header phrasing etc.) in order to A/B test our UI/UX. I should note that nothing significant (i.e. sitemap) is changing, just some minor presentational aspects.
There are several possible approaches, namely using different view templates / helper snippets, or serving up a different stylesheet. Both have advantages and challenges, and ideally the same visitor would always be served the same version. Results would be fed through a service like Mixpanel.
I fear I may have to roll my own solution here, but would love to hear any suggestions / pointers.
At their root, most A/B javascript testing frameworks cookie a user as being in the "A" or "B" group, give you a way to ask if a user is "A" or "B" and report "results" back to a service to measure. This can plug into Ember or other client-side frameworks in a way that is fairly orthogonal to the framework.
I would recommend exposing the "A"- or "B"-ness of the user as a property on your user (in Ember, probably your UserController). Then you can use your framework's standard branching or conditionals to render the "A" UI or the "B" UI.
I have actually built a pretty robust A/B Testing tool using Ember for my startup. We are actually thinking of open sourcing it if there was a demand for it. I can let you know the basic idea of how it works for now though.
I have landingPage objects, that can then have a bunch of A/B tests associated with the, When a user comes to the landing page, they are assigned a cookie, and for each A/B test that are assigned either A or B.
I have used two different approaches within jade to handle A/B testing.
For styling type things, I use something like this
and set the .css property in the view to either test-a or test-b
or if it is for text I will do something like this
{{view view.landingPageText}}
and the landingPageText would be set to either the text for A or the test for B.
This thing also dynamically sets up mixpanel, mailchimp, and uses parse.com and node. You can see the code in action here.
http://golf.nextstudioapps.com/