21 ms·

EmberJS Confuses Me

291 points by statenjason 14y ago

gosukiwi 14y ago
Well, I don't know EmberJS but for the handlebars code you showed, seems like the controller is somewhat more like a ViewModel (MVVM pattern), maybe learning KnockoutJS first would help a bit?
- msarchet 14y ago
  Rob has done knockout, and that's pretty unrelated I feel. I've spent a lot of time doing Knockout and a fair amount of time in Angular and Backbone, and personally I sort of agree with what rob is saying. I feel like they have taken MVC and just loosely applied it in Ember, because they have Models Views and Controllers. I see and understand where his confusion is coming from. I probably also haven't spent enough time with Ember to get it, but I also don't feel like I want to.
  - gosukiwi 14y ago
    Well maybe it helps to wrap your mind around Ember controllers. From what I read, I'd rather use Backbone.
pilgrim689 14y ago
> The downside to this approach is that your HTML is "compromised", if you will, and many developers don't like that. My thought is that it's already compromised using Handlebars so what's the difference here? Personally I have no issue using the ng-* directives. Some people do, and I respect that. I'm a bit off-topic, but you don't need to "compromise" your HTML with AngularJS, you can place "data-" in front of your attributes and you're HTML-compliant again :).
- robconery 14y ago
  Absolutely true - I should add that in. I think people look at that, however, and don't like functionality etc. shoved into the DOM. But your point stands.
  - MatthewPhillips 14y ago
    This is addressed in the article, the Handlebar templates have functionality too.
- xaritas 14y ago
  When I hear this argument I believe the concern is not the syntax of the binding with respect to the HTML spec, but rather the declaration of bindings in HTML at all. So the issue is not "ng-click" vs. "data-ng-click", but that "ng-click" in any form is no different than the pre-JS MVC horrors of onclick="mutateGlobalStateAndPerformIO()"; which is precisely the barbaric approach we thought we were vanquishing. I think that some people prefer to see bindings sprinkled on the DOM via code, as part of the bootstrapping process. I haven't used Backbone for a year but I'm pretty sure it is a strong proponent of "let nothing live in the DOM" school of thought. I don't subscribe to that, by the way, but that's the argument.
  - daigoba66 14y ago
    > onclick="mutateGlobalStateAndPerformIO()" What's wrong with that? Other than scoping problems (which Angular solves), this is far more in line with classic view-controller than anything else.
    - xaritas 14y ago
      Nothing, but some feel rather strongly averse to it, and plainly view this as Angular's self-evident fatal flaw. As I said I do not subscribe to this line of thinking. My allusion to the horror and barbarism of the pre-JS MVC was merely a jape.
    - MatthewPhillips 14y ago
      What happens when you want to add a second, unrelated, thing? Just stick it on the end in the onclick? Create a new function called doTwoThings()? This is one of the reasons I prefer using an observer pattern over MVC.
      - aidos 14y ago
        That doesn't really happen though - also, Ng-click is a specific directive you can choose not to use. A more general argument is that any behaviour specified in markup is bad. I'd counter that by saying that it's already there in HTML. Input boxes for example have behaviour intrinsic to their being. So angular let's you create a (for example) richtext tag. You attach behaviour to that tag, say on click. In the HTML it's as clean as <richtext>. Within the directive you can make it behave as you please. I think that people see the shortcut directives used in angular (eg Ng-click) and the purists shout "unclean"! The reality is that You can do things a slightly longer way and end up with something thy looks a lot like the observer pattern.
clintjhill 14y ago
The examples provided to describe the difference between controllers in Ember and Angular do not appear to be different to me at all. In fact I'd argue that they are identical. It feels to me as though the author is wanting them to be different because maybe it's a style preference from the templating perspective?
- robconery 14y ago
  The examples were to show how $scope is used in Angular vs direct use of the Controller/Model proxy in Ember. This makes a bit more sense to me, personally.
  - clintjhill 14y ago
    Except you could write identical code in Ember as well when you extend the controller. Replace "$scope" with "content" and it's identical.
    - robconery 14y ago
      Interesting - didn't know this. $scope is injected by Angular and available to the view - is this the same thing? I didn't think Ember had a DI aspect to it.
jacquesc 14y ago
Really nice constructive writeup (as always by Rob), and I think it should be addressed by some better EmberJS docs and tutorials. They do a good job explaining the "what", but it could probably use more "why". It took me a while as well to figure out why controllers proxied to models. However it started to make a lot of sense in when building an app, since the controllers are there to stay around, and the models are swappable. Having the option to easily swap out a model at the controller level is worth the extra layer abstraction. That and the ability to add additional UI specific properties on the controller that don't necessarily belong in the model (since they don't need to be persisted).
ZoFreX 14y ago
Thanks for sharing this Rob, it was actually very informative about Ember to a newbie!
jfarmer 14y ago
I've never used EmberJS and am not familiar with any of the front-end JavaScript frameworks, but I don't get what's confusing. It looks like instead of the controller pushing data to the view, the view asks the controller for data (which it might proxy to the model). This makes sense with a long-running controller, right? On the web both the controller and view are ephemeral -- they last for just that one request -- but if the controller is running continuously then it needs to reflect changes in the models as they happen. The model(s) the controller references can change without the view changing its reference to the controller. Without something like this the view would render stale data. I'm assuming this is why we have a controller.model, to add that layer of indirection. What am I missing? How is this more complicated making the controller<->view relationship pull instead of push?
- robconery 14y ago
  The controller is the data. The model is grafted onto it for convenience. This ties the view to the model to the controller which is sort of orthogonal to "separation of concerns". In my opinion at least.
  - clintjhill 14y ago
    The controller is responsible for rendering the view when the data changes. It does graft the model data - and any other data you want renderable into the view. I wouldn't characterize it as "the data" however.
    - robconery 14y ago
      {{#each controller}} {{name}} {{/each}} How is the controller not the data as far as the View is concerned?
      - acoleman616 14y ago
        As mentioned above, the proxied model data is actually stored in a controller's "content" field. So that snippet is actually just shorthand for {{#each controller.content}} {{/each}}
pspeter3 14y ago
Watching the peep code screen cast helped a lot
- BaconJuice 14y ago
  can you post a link to this?
  - rizumu 14y ago
    https://peepcode.com/products/emberjs https://peepcode.com/products/emberjs
ghurlman 14y ago
Here's the Google cache: http://webcache.googleusercontent.com/search?hl=en&biw=1256&bih=787&sclient=psy-ab&q=cache%3Ahttp%3A%2F%2Fwekeroad.com%2F2013%2F03%2F06%2Fember-confuses-me&oq=cache%3Ahttp%3A%2F%2Fwekeroad.com%2F2013%2F03%2F06%2Fember-confuses-me&gs_l=hp.3...9193.10065.1.10319.6.6.0.0.0.0.70.287.5.5.0.les%3B..0.1...1c.1.5.psy-ab.Z1SKTeDnL-M&pbx=1 http://webcache.googleusercontent.com/search?hl=en&biw=1... text-only: http://webcache.googleusercontent.com/search?q=cache:http://wekeroad.com/2013/03/06/ember-confuses-me&hl=en&biw=1256&bih=787&strip=1 http://webcache.googleusercontent.com/search?q=cache:http://...
randall 14y ago
The Angular example is a bit incorrect... when you do an ng-repeat, you're going to do like ng-repeat="person in people" and then each template item will be like {{person.name}} as opposed to just {{name}}. Just a little clarity in the code. Thanks for the writeup!
- robconery 14y ago
  This is fixed - thank you.
ef4 14y ago
> When talking routes, urls, and resources - that's a RESTful consideration and involves stateless state "stuff" (sidestepping the REST debate here). What is this concept doing in a desktop app?. Ember is explicitly not about "desktop apps". That's actually why Ember broke off from Sproutcore. Ember is very opinionatedly focused on building web applications that are native to the web and stick to web conventions. The best web applications still behave like the web is supposed to behave: they have shareable, bookmarkable URLs that allow the application's state to be recreated. This is a big reason Ember's router is different than the other examples you mentioned -- in Ember the router automatically handles a lot more of the state reconstruction stuff.
- robconery 14y ago
  The team has been rather clear that Ember is Desktop MVC, not web/server based: https://twitter.com/trek/status/309315009291378690 https://twitter.com/trek/status/309315009291378690 They say as much in their guides as well.
  - ef4 14y ago
    > The team has been rather clear that Ember is Desktop MVC, not web/server based That's orthogonal to what I'm talking about. I agree that their use of the term "MVC" is much closer to the original meaning it had on the desktop (like in Cocoa) than the meaning in server-side frameworks like Rails. But I'm not talking about what MVC means. I'm talking about what kind of applications Ember is intended to be used to build. A flagship example would be Discourse, which is very deeply web-focused, and nothing like the way you would structure a desktop application.
    - robconery 14y ago
      Your assertion is that "Ember is not about desktop apps". Yes, it is entirely about Desktop apps in terms of structure and approach. These apps are built on the web. One look at the Discourse Ember code and I think you'll understand perfectly the confusion I'm writing about. But I'm curious: do you use Ember or are your responses "what you think"
pixelcort 14y ago
Think of Ember controllers as proxies, or pointers if you will. The idea is you can have a commentsController instance, and when you switch to a different post, the view(s) bound to it will automatically pick up the new comments array that is swapped out on behind the controller. Routing is just rewiring the pointers on your controllers and getting the right views up on the page.
avolcano 14y ago
While I actually totally agree with the confusion in the router, I want to explain what I see in Ember's MVC: As far as I attempted to implement it in my app (https://github.com/thomasboyt/noted-app https://github.com/thomasboyt/noted-app), it seemed simple enough. Models were data; all they contained was their properties and operations that controlled their properties. I mainly used controllers as the "state" for parts of my app. In Ember, this doesn't even need to mean it's tied to a specific model type. For example, my Dropbox integration is handled within a controller that's bound to several separate views (in this case, those views included buttons that triggered syncing and modals that displayed the progress of syncing). There's no "Dropbox model," just other models that I'm using this controller to sync. Controllers are not simply an intermediary between models and views, they are an intermediary between state and views. > I'm trying my best to reconcile this with the notion that a controller (classically speaking) is supposed to ... well control the view. Here, it's not doing that. I think what the author was looking for in controllers is what's actually handled by, well, views. The view handles any user interaction, and then uses the controller to change the state of various bits (whether calling methods in the controller or simply updating properties on it). To sum up: model is data, controller is state (including instance(s) of models), and the view is user interaction. Templates can bind to properties on any of these. Routes are what hook these components together depending on the page.
- robconery 14y ago
  Seems reasonable, but the Ember team sees it differently... they put state in the router: >Most of your controllers will be very small. Unlike other frameworks, where the state of your application is spread amongst many controllers, in Ember.js, we encapsulate that state in the router. This allows your controllers to be lightweight and focused on one thing.
  - avolcano 14y ago
    Well, clearly, they are crazy people. Nah, kidding. So they're totally right that there's a significant amount of state in the router, in that that's where you define which model and controller (and, depending on how fancy you get, what views and templates) to use on a given page. So those are essentially state. The state that can make a controller fat is essentially state that's too important for a view but doesn't need to be universal to the page. For example, with my Dropbox controller, the controller has a state property that handles the various permutations of the state of syncing (i.e. it could be doing nothing, currently saving, done saving, failed saving, etc.). This state is set by the controller on the controller, and used by multiple views to determine things like which label a progress modal should have. For example, if you had a controller representing a list, you might want to keep track of which item is selected on the controller. That way, if there are multiple views that can act on the currently selected item (for example - you might have a list item view that has a template that renders the item, and then a separate view that are buttons that trigger actions that act on the current item), they all have access to it. Plus, I always think of state defined in a router as being limited to specific pages/routes, whereas some of my controllers are used on several different routes.
mark_l_watson 14y ago
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seivan 14y ago
Wonder how many iOS developers feel home with Ember? I don't. I also do Rails, and I feel more at home with Batman than Ember.
tree_of_item 14y ago
I think the problem is MVC itself is a confused mess. It means whatever each person wants it to mean, since it's too easy to make up a bunch of reasonable sounding argumentation for whatever you want to do if you use the words model, view, and controller a lot.
- agpen 14y ago
  Yeah, I even wrote my own MVC framework for a small project and I still don't know what MVC is "supposed" to mean because every single implementation example I see is completely different and at odds.
- chipsy 14y ago
  This is the comment I agree with most. Replace a solution defined as a "design pattern" with one defined as a data structure and you get a lot more clarity. The problem MVC solves can be recomposed as "synchronization of concurrent, related, mutable data structures." The relations are definable as a DAG for each direction; the synchronization process with a cyclical graph.
  - rapind 14y ago
    "Synchronization of concurrent, related, mutable data structures" is totally clear to me.
- sergiosgc 14y ago
  That, coupled with the fact that MVC (the classic, desktop MVC) seems shoehorned in webapps, makes me weary when frameworks tout their MVCness before stating their distinctive features. BTW, I'm much more adept of removing the controller and going to a tightly coupled stack of view-model with the use of the observer pattern where needed. Controllers remind me of that extra indirection that seems useful in design but is never really used and is thus just unnecessary complexity.
- e12e 14y ago
  I feel that as with many things in Computer Science, the original MVC-stuff is regrettably "under-read"[1] by a lot people. I highly recommend having a look at the various links on: http://heim.ifi.uio.no/~trygver/themes/mvc/mvc-index.html http://heim.ifi.uio.no/~trygver/themes/mvc/mvc-index.html for those that haven't read what the original model-view-controller-user idea was all about. It makes more sense from a Smalltalk/Self/Object-C/Message-passing style of object orientation ("true object orientation") than from java -- in this sense it should be a good fit for javascript as well -- but unfortunately java/c++ style object orientation (really "class-inheritance orientation") have bastardized MVC to mean something subtly different (I am not quite sure what, exactly, but I don't think I'm the only one...). [1] "Well, I'm an old-fashioned guy. And I also happen to believe in history. The lack of interest, the disdain for history is what makes computing not-quite-a-field." -- Alan Kay http://www.drdobbs.com/architecture-and-design/interview-with-alan-kay/240003442 http://www.drdobbs.com/architecture-and-design/interview-wit...
terbanator 14y ago
Your examples are incorrect. The Route's model is set as the content of the controller, so all you need to say is #each item in content. Your model is set as the "content" of your controller, so your model is not "nowhere to be found"
- terbanator 14y ago
  http://jsfiddle.net/sgterban/kDqBs/ http://jsfiddle.net/sgterban/kDqBs/ - Example
  - drogus 14y ago
    You should use {{#each item in controller}}, otherwise you won't get things like sorting of filtering right. Yes, content is an underlying array, but controller may present it differently (filter out, sort, paginate etc.).
- twinturbo 14y ago
  content is wrong. You should be using controller. This works with arrangedContent. {{each content}} will not work with anything like SortableMixin.
newishuser 14y ago
Don't give up! Ember has a steep learning curve but once you've got a bunch of it memorized development gets much easier.
- jonny_eh 14y ago
  I learned Angular instead since it was easier to get my feet wet with it and seemed to make sense to me. Am I missing something by not using Ember?
jhysum 14y ago
Instead of controlling the view directly from the controller, the view uses the controller object (proxy to model) in any way it wants allowing you to change the view without changing the controller and same with the controller. I think the issue you are facing is thinking that you are tightly coupled to the controller by using the controller object, depending on what you think about how much coupling is too much coupling you can argue that just using one object might really be decoupling. I'm not sure if I was able to get my point across.
Tichy 14y ago
I think the way controllers work here is similar to Ruby on Rails? It confused me in Rails at first (coming from the Java world), but I think it is essentially just a hack to allow for "easier" passing of data to the view (the controller gets exposed to the view). So instead of scope.whatever = "hello world" you can write this.whatever = "hello world" (OK not really shorter, but something like that). That usage of Controllers is not part of the MVC pattern, I'd say. It's just a recycling of the controller instance - not forbidden, just confusing if you wonder what it has to do with MVC. Actually it's also the RoR way to have short lived controllers (a controller is instantiated for every request), other frameworks use one static controller instance instead.
anarchotroll 14y ago
Seems like the big confusion about the controller is that it is closer to a ViewModel (think MVVM) than to a Controller itself. Potatos, Potahtos.
- mcgwiz 14y ago
  That's the hunch I had reading this (as someone with no EmberJS experience). To digress a little, it's not much different than the terminology confusion in Backbone, where: - Router(s) work as front controllers, - templates (along with the browser's DOM) as views, and - Views as presenters (from the MVP pattern). Models are flavored with the Active Record pattern. Presenters and views are tightly coupled. MVC and MVP coexist because the controllers respond to navigational input (mapping to model-presenter pairs) and the presenters respond to page-specific input (mapping to model manipulations and, possibly, server calls).
- Kiro 14y ago
  Model, View AND ViewModel? What kind of confusing terminology is that? I use KnockoutJS but I still don't understand why it's not just called MVC.
devinrhode2 14y ago
At first read, I thought your point about routing was really good - why not have route('about').template('aboutTemplate').controller('aboutController') - and then I realized this is all reapeating the same mumbo jumbo. This is all automatically matched up by the naming convention (which frustrates me too, but until I figure out a better way...)
andreipop 14y ago
Take a look at Yehuda's talk from Seattle: http://www.youtube.com/watch?v=4Ed_o3_59ME http://www.youtube.com/watch?v=4Ed_o3_59ME - I think it explains a few things very well, and helped me out a ton
sandstrom 14y ago
Although really old (and outdated) I found this Sprout Core introduction useful. The first 3-4 minutes was enlightening for me. http://vimeo.com/24487742 http://vimeo.com/24487742
tonycoco 14y ago
Curious for yourself? Try following my simple starter app tutorial of Rails + Ember.js here: http://www.devmynd.com/blog/2013-3-rails-ember-js http://www.devmynd.com/blog/2013-3-rails-ember-js Though, I understand the pain of coming from a server-side MVC architecture, I found it refreshing that Ember.js takes the "desktop" MVC approach. Our web apps are now living on the client, acting like desktop apps. Most people struggle with this reverse at first, but can conceptually catch on if shown the way. I think what really needs to happen is a good screencast or two walking through these concepts. I'm interested in putting something together and will when I have the time.
- tmzt 14y ago
  While there is quite a deal of information on integrating ember-data with rails, there is much less on integrating it with other server-side MVC/REST frameworks. This means that using it with another framework often means modifying that interaction pattern to be more like how rails views ajax, complete with the root objects ({"model":{}}). This may more accurately apply to the REST driver in ember-data, but that is quite tightly coupled with the rest of it.
  - tonycoco 14y ago
    That's def a job for the adapters. Django, for instance, has a REST adapter that has been worked on here: https://github.com/toranb/ember-data-django-rest-adapter https://github.com/toranb/ember-data-django-rest-adapter As far as the root objects are concerned, I've always been a fan of that part of Rails. Not to say that it cannot be easily gotten rid of with something like this (for ActiveResource)... ActiveResource::Base.include_root_in_json = false Or, like in my example app, with this (for ActiveModelSerializers)... https://github.com/rails-api/active_model_serializers#1-disable-root-globally-for-in-arrayserializer-in-an-initializer https://github.com/rails-api/active_model_serializers#1-disa...
- ffreire 14y ago
  There seems to be some very positive buzz around this screencast mentioned both in the OP's blog and around HN in general: https://peepcode.com/products/emberjs https://peepcode.com/products/emberjs . I found it particularly instructive but found that it only scratched the surface of this new framework. At least, it scratched enough off the top that I feel comfortable rooting through source and API documentation to figure out the rest. YMMV, of course.
sideproject 14y ago
I come from Backbonejs background with which I have worked for about 1.5 years. So I feel quite comfortable with it. I decided to try Emberjs - not for any other reason than trying to pick up something else and see how other JS framework approaches. I gave full two-days worth of time into it. Initially I thought - "How different can it get?" Plus, I believe even if it's very foreign I'll just keep reading, googling, stackoverflowin', youtube-tutorialin' to get my head around. I gave up though. Here's my hopefully constructive rant, though my views are probably not as deep as the OP's. * Many of the posts on the net are outdated. I followed a few tutorials here and there, and then things didn't work, so I asked on Stackoverflow, then the answer I got was "Dude, your code is outdated". Sure this is probably similar thing for other frameworks - but I'm just sayin' * Models - So there is Ember Object, which you can use as models, but you can also use Ember-data.js which is more "glorified" data. Documentation wasn't clear on the difference. Plus, Ember-data.js was quite hard to get started with. It didn't work well with other versions of Emberjs. I really had to dig in to find the right one to start off with. I ended up cloning a github repo of a tutorial that worked, because nothing else did. * Documentation on "convention over configuration" - OK, so convention over conf. is fine. But the official documentation and many of the tutorials didn't explain what all the conventions there were. I went through a tutorial app, which only had Controller, but things just "worked", because the Emberjs builds all other things for you. Well I didn't know that! THE BEST INTRO EMBERJS VIDEO I found was this. http://toranbillups.com/blog/ http://toranbillups.com/blog/ It finally made sense in the end for me. * But in the end, among all other things I wanted to do, I gave up, because the frustration was mounting up. I guess I can still persist through it. But I just finished AngularJS tutorial demo and in 2 hours, it makes sense to me.
- rxcfc 14y ago
  The Ember teams has been planning for a sweep of all outdated information about Ember. We'll be updating SO questions and asking blog authors to add a disclaimer. Ember Data is a completely optional component of Ember that seeks to bring ORM-like abilities to the client side. It's not as far along or as stable as core Ember. For what it's worth, you can easily just use jQuery.ajax and create Ember.Objects from the response. We probably do need better documentation in this area to make this clear. That said, it's not fair to count Ember Data as a point against Ember since no other framework has anything at all similar in scope. Our overview documentation is lacking. This is something that we're actively working on improving. The hardest part for new developers coming to Ember is that the paradigms are very different than what they're used to. We believe that the paradigms are the correct ones, but we need to do a better job explaining them.
tericho 14y ago
I'm by no means an "expert" but I shared the same struggles and after 2 weeks of trying to build a complex app I gave up. I switched to Angular (which I also had never used before) and got the same app up and running in a couple days with even more functionality because I was able to hash lots of the trickier "outside-the-box" functionality that I could not for the life of me get working in Ember. That being said I really like Ember's syntax, Handlebars integration, core values (performance & stability specifically) and have the utmost respect for its creators. I'm hoping since it hit 1.0 that lots of new sample apps, blog posts and SO-type Q&A resources will start showing up and actually stay relevant for more than a month.
nirvanatikku 14y ago
+1. you hit the nail on the head and articulated what I was feeling when I played with ember.
richo 14y ago
> I think Yehuda is a very nice and smart person I always get confused by this. I don't understand how being nice factors into technical decisions? (For the record, I also think wycats is nice, but I don't really care when I'm trying to decide whether or not what he's saying makes sense)
- rcourtie 14y ago
  I assume it's to say that he doesn't have some sort of vendetta or dislike of Yehuda that's coloring his opinion.
- davidw 14y ago
  If you need help, want to suggest a modification, or otherwise need to interact with the author(s) of something you're using, it's nice to have friendly people to deal with, rather than assholes, all else being equal.
  - richo 14y ago
    I hadn't thought of it that way.
stevewilhelm 14y ago
> Ember is explicitly not about "desktop apps". That's actually why Ember broke off from Sproutcore. Ember is very opinionatedly focused on building web applications that are native to the web and stick to web conventions. This may be the issue. I think most of us never really wanted to build web applications, but we were forced to do so due to browser and framework limitations. We really just wanted to build the best damn desktop app possible that just happened to be deployed in a browser via the Web. This might explain our confusion and disappointment when client side frameworks don't deliver on that desire.
- rxcfc 14y ago
  Are you implying that Ember doesn't deliver on this desire to build desktop class applications in the browser? If so, can you explain where it falls short?
- Pherdnut 14y ago
  Most of whom? I came up in JS on the client-side. Nothing has been more frustrating over the years than watching all of the inflexible bloat and tightly coupled BS people have been piling on to the client-side in order to pretend it was something that it is not. Web forms sucked ass. Everything Java tried to do to pretend the client-side wasn't there has left massive legacy potholes all over the web. Just deal with the thing as it is already and learn something new. You're a programmer for chrissakes. I might indulge in writing OS apps with webkit but I don't try to add a server to the process if it's just a local desktop app in order to make it more like what I'm used to. HTML, CSS and JS properly applied are doing 4/5ths of what these frameworks are pointlessly reinventing. All you have to do is learn them properly. The rest, keeping data loosely coupled, is basic 'duh' OOP. All the stuff that's already there works surprisingly well if you actually give it a chance. Or have you not noticed that web technology solutions are spreading like wildfire into other domains or that we can implement and modify GUIs using client-side-web-technology a lot faster than desktop OS UI developers have ever been able to? FFS, they don't deliver on that desire because it's proven time and time again to be a complete waste of time to try to.
BlindRubyCoder 14y ago
The whole point of EmberJS confuses me.
gavanwoolery 14y ago
I have not used Ember, but you mention MVC, which immediately brings to mind Sencha. I have used Sencha a lot, and although I think it is mostly great, I do not like how they try to pidgeon-hole you into the MVC methodology, which just does not make sense in many contexts.
selvan 14y ago
I tried Emberjs and Angularjs recently, as both framework offered two-way binding between view & model, at client side. Angularjs was easy to pickup and I have completed what I wanted to do in about half a day, except one issue, angularjs template rendering is DOM driven. I wanted server-side templates, hence I have to boot phantomjs at server-side. I didn't quite like booting phantomjs for server-side templates. Since Emberjs offered, handlebar based templates, I was happy that I could render my templates at server-side. So tried emberjs, it took about 3 days, to get it done. Many out dated tutorials & documents spread across internet about older versions of Emberjs. Documentation at emberjs.com is minimal and not helpful. I started looking at source code of discourse.org and try to understand how they used ember. I felt the power of emberjs when I needed complete control of context and rendering of nested templates. It was real beauty.
- deleted 14y ago
  [deleted]
- Kiro 14y ago
  In what circumstances would you want server-side templates and how come it's easier with Handlebars?
  - davedx 14y ago
    SEO.
    - e12e 14y ago
      Not only SEO. If you need to build a webapp that is also a web page (eg: blog, wiki, cms) -- you want a rich client, but also relatively plain pages -- and ideally you want to share code/templates where it makes sense.
      - masklinn 14y ago
        Also to improve "bootup time", from request to usable: server-rendered templates can be cached, can provide at least visible content before javascript even has to run and can use beefy servers & the like. At that point the client "only" has to do the events binding wiring and it's done.
fcatalan 14y ago
Ember confuses me too. I've worked with many server and desktop MVC frameworks for almost 20 years. I'm familiar with MVC, it plays simple and easy, like rock-paper-scissors. My problem with Ember is that it seems to be more like "rock-paper-scissors-lizard-spock but for us the rock punches through the paper and the scissors cut the rock like butter. And you can play without actually showing your hand". Confusing.
pradeepin 14y ago
Yes, I too agree EmberJS always a confusing library, Following are my resaons. 1)They say it follows MVC. Its actually MVC but MVP, if you look closely at the implementation. 2)Controller job is not precisely defined. Example: Even the data validations are done at controller level not a model level So i switched to Backbone.js, which is very flexible library with tons of plugins that can be used when needed. Since implementation of UI is different from requirement to another requirement. I feel EmberJS doesn't satisfy this, which leads to people using Backbone.js. Regarding AngularJS, please use it only if you are new javascript and prefer learning Angular Javascript (which is not javascript by the way) :)
- ganarajpr 14y ago
  Regarding AngularJS, please use it only if you are new javascript and prefer learning Angular Javascript (which is not javascript by the way) :) I am not sure you "know" javascript. If you are saying that there is an Angular version of javascript then you are terribly mistaken. Angular is probably one of the only mainstream framework that stays true to javascript. All other frameworks ( Backbone, Ember etc.. ) are the ones that actually mould javascript into an OOP language. I would say that Angular uses the prototype chain ( you know javascript is a prototypical language right? ) the best. The whole scope object inherits prototypicaly while in all other frameworks we create an illusion of OOP. Someone correct me if I am wrong here. Just for clarity, I believe that when you write Angular code you are writing the purest form of javascript. Because thats what you are writing there. Just plain javascript. There is no constructs imposed by the framework at all. This is probably why most people think "Angular's javascript" is not javascript. They have been always fed layers on top of javascript because "javascript is somehow not optimal, not right" and it has to be "changed" and "corrected" . OOP is shoved down the throat. This is probably gone on to the extent that when someone actually writes in pure javascript it starts looking like a foreign language !!
  - WickyNilliams 14y ago
    Before berating other people's knowledge, you should probably make sure that what you are saying is infallible. So with that I ask you: Do you realise that JS is an object oriented language? Prototypes are a means for inheritance (i.e. reuse of code), just as classes are in more traditional languages - it does not mean JS is not OO. My interpretation of the GP comment is that he means angular to JS is like jQuery to JS, it's effectively a DSL that you have to learn in itself. Someone once said "people don't write javascript anymore, they write jQuery". That's what I think he meant
xmlninja 14y ago
You are not alone.
jondot 14y ago
In the past I've been working on enterprise application suites for the desktop. The kind of monstrous applications that run on electronics manufacturing floors. Such a typical application has a shell, modules, inter-module communication, dynamic module loading, plugins, and much much more. One can think of it as Eclipse with its ecosystem. To build such a system on the Enterprise with its typical NIH (not invented here) paranoid attitude was VERY hard. I had to reinvent a lot of wheels. On the Web, I've used backbone for a long time now, since almost the time it was out. I saw the same problems building complex applications with it (that backbone-marionette amends to a great deal). For a larger project, I evaluated Angular. Had very strong negative feelings about it. Then I tried Ember. It took me a long time to "get" it. The only thing that kept me motivated is knowing that Yehuda, Tom and Trek and other capable people are contributing on it. I kept fighting through the outdated tutorials, the outdated videos, and even the peepcode video was embarrassingly confusing to me at some point. But then it hit me. Ember and its infrastructure, the way its MVC is rigged, was very similar to what I was building from scratch on the desktop many years ago. It truly IS the one framework that "gets" desktop, or client-side, applications. The causer of my confusion was that I didn't completely let go of the "Web-think" for building application. I was stuck at either server-side MVC (MVP), or bare-bones frameworks such as Backbone. It's been just too long out of the real complex desktop game for me, to realize what that I'm looking at is a proper MVC framework. So for me, Ember ended up as being great - it still takes me back to the way I was building desktop applications, and I'm sure it will become even better and better. To understand it, you need to cold-boot your thoughts into that classic desktop MVC place; and if you were never in it, I think Ember is an excellent way to get into it as opposed to other frameworks.
itsbits 14y ago
I have been into MVC frameworks for 4-5 months now...mostly used BackBoneJS before switching to EmberJS..conceptually I did felt EmberJS very tough in the beginning..i was worried whether i made the right choice in using EmberJS for my product..but now with the latest 1.0rc2, its so easy in development..routing has been improved very much..Binding is the awesome feature i liked and helps me thgh..an added advantage over BackBone...i cant say about angular..but am quiet happy with EmberJS...
melc 14y ago
i've been using ember for the past three months in a fairly complex project and i'm very happy with it ; a platform that builds business web apps dynamically for devices (20+ pages,250+ fields per app with validations, calculated fields, conditional flows etc , rendering/theming in jqm -> packaged with phonegap) and client web browsers (render/theme in bootstrap),the backend is in java. So, i certainly don't feel the same way for emberjs as the writer. I had decided to build the frontend in a js mvc framework and the candidates were backbone, emberjs (pre version), angularjs. Read about them and gave backbone a try, however from the documentation only emberjs approach felt better maybe because of a similar in-house development java framework that we work on. So i tried to give emberjs a try at the same time, due to the tight deadlines. I dropped backbone, and spent more time on emberjs because everything simply worked and fitted together nicely. All these binding mechanisms are great and actually work :) . Haven't tried angularjs. The system now works with emberjs (pre and rc) with a nice layered architecture and separate independent business logic modules. My advice is to read the documentation carefully and choose what fits better to your needs and coding styles.
nXqd 14y ago
The only reason is you are in love with AngularJS. I will find someone who really hates angularJS because if we have a lot of validation, it will become a messy of ng-*. So no matter which framework we use, we should talk about real world project. Not simple usage that only exists in trying and testing. Use the framework, you love and you will make it beautiful no matter what :D
- jonascopenhagen 14y ago
  > I will find someone who really hates angularJS because if we have a lot of validation, it will become a messy of ng-* Are you talking about HTML validation? AngularJS supports using data-ng-* which means it's valid HTML.
- ebiester 14y ago
  At this point, you write a directive. Your directive should be watching your model and adjusting as appropriate, rather than trying to fit everything into the provided.
sudhanshu80 14y ago
We have applied EmberJS to a fairly complex application backed by Rails backend. We had to deal with complex JSONs delivered by backend which were schemaless MongoDB documents. At lot many places we had non RESTful Rails controllers. So when we started with EmberJS we had a worry the documentation was not proper, there were very few reference projects. After a few weeks of thrill and steep learning we settled on with things. We have applied a lot of functionalities offered by Ember to our code. Migrated from router from old to new api of pre 4. But we feel in our team it was right thing to apply Ember. The way overall MVC imposes structured programming, the way HTML is seperated from JS, the way ember data can have serializer and adapter customized, two way bindings all of it had been useful. We struggled at few places with deep nested JSONs in hasMany/belongsTo relation in embedded JSONs. But doing workarounds were easy. We used fixtures to hasten development while backend was not yet ready. All in all we believe that we made a good choice to stick with Ember, though it looks difficult to comprehend on the start but thats also getting better with time.
visarga 14y ago
I just think the basic idea is to keep things as separate as possible, to keep complexity down. Just encapsulate things OOP-like, hide the guts, and provide a clean access API to them. That makes it manageable.
Pherdnut 14y ago
I'm confused by all of these MVetc... libraries. We had routing behavior to content/views covered already. How is anything that does more than help isolate/manage data more than cruft in regards to having some sort of MVC-but-not-really-style-app on the client-side-web? IMO, it's all just pointless abstraction of the type that JS devs should have learned to avoid from observing server-side fail over the years. What really blows my mind is the number of these frameworks that embed pointless behavior dependencies directly in the HTML and act like they're doing us a favor. That's awesome, now we're back to changing things in multiple places to make adjustments to our apps that used to happen in one place following basic "duh" best practices that the authors of these frameworks don't appear to have ever understood properly. HTML is the router you saps! Hell, how about we add pointless-in-a-language-with-first-class-function IOC fail, config files and pointless dependency management as well? Wait WHAT!? ARE YOU !@#$ING SERIOUS!?

291 points by statenjason 14y ago

Well, I don't know EmberJS but for the handlebars code you showed, seems like the controller is somewhat more like a ViewModel (MVVM pattern), maybe learning KnockoutJS first would help a bit?

msarchet 14y ago
Rob has done knockout, and that's pretty unrelated I feel. I've spent a lot of time doing Knockout and a fair amount of time in Angular and Backbone, and personally I sort of agree with what rob is saying. I feel like they have taken MVC and just loosely applied it in Ember, because they have Models Views and Controllers. I see and understand where his confusion is coming from. I probably also haven't spent enough time with Ember to get it, but I also don't feel like I want to.
- gosukiwi 14y ago
  Well maybe it helps to wrap your mind around Ember controllers. From what I read, I'd rather use Backbone.

pilgrim689 14y ago

> The downside to this approach is that your HTML is "compromised", if you will, and many developers don't like that. My thought is that it's already compromised using Handlebars so what's the difference here? Personally I have no issue using the ng-* directives. Some people do, and I respect that. I'm a bit off-topic, but you don't need to "compromise" your HTML with AngularJS, you can place "data-" in front of your attributes and you're HTML-compliant again :).

robconery 14y ago
Absolutely true - I should add that in. I think people look at that, however, and don't like functionality etc. shoved into the DOM. But your point stands.
- MatthewPhillips 14y ago
  This is addressed in the article, the Handlebar templates have functionality too.
xaritas 14y ago
When I hear this argument I believe the concern is not the syntax of the binding with respect to the HTML spec, but rather the declaration of bindings in HTML at all. So the issue is not "ng-click" vs. "data-ng-click", but that "ng-click" in any form is no different than the pre-JS MVC horrors of onclick="mutateGlobalStateAndPerformIO()"; which is precisely the barbaric approach we thought we were vanquishing. I think that some people prefer to see bindings sprinkled on the DOM via code, as part of the bootstrapping process. I haven't used Backbone for a year but I'm pretty sure it is a strong proponent of "let nothing live in the DOM" school of thought. I don't subscribe to that, by the way, but that's the argument.
- daigoba66 14y ago
  > onclick="mutateGlobalStateAndPerformIO()" What's wrong with that? Other than scoping problems (which Angular solves), this is far more in line with classic view-controller than anything else.
  - xaritas 14y ago
    Nothing, but some feel rather strongly averse to it, and plainly view this as Angular's self-evident fatal flaw. As I said I do not subscribe to this line of thinking. My allusion to the horror and barbarism of the pre-JS MVC was merely a jape.
  - MatthewPhillips 14y ago
    What happens when you want to add a second, unrelated, thing? Just stick it on the end in the onclick? Create a new function called doTwoThings()? This is one of the reasons I prefer using an observer pattern over MVC.
    - aidos 14y ago
      That doesn't really happen though - also, Ng-click is a specific directive you can choose not to use. A more general argument is that any behaviour specified in markup is bad. I'd counter that by saying that it's already there in HTML. Input boxes for example have behaviour intrinsic to their being. So angular let's you create a (for example) richtext tag. You attach behaviour to that tag, say on click. In the HTML it's as clean as <richtext>. Within the directive you can make it behave as you please. I think that people see the shortcut directives used in angular (eg Ng-click) and the purists shout "unclean"! The reality is that You can do things a slightly longer way and end up with something thy looks a lot like the observer pattern.

clintjhill 14y ago

The examples provided to describe the difference between controllers in Ember and Angular do not appear to be different to me at all. In fact I'd argue that they are identical. It feels to me as though the author is wanting them to be different because maybe it's a style preference from the templating perspective?

robconery 14y ago
The examples were to show how $scope is used in Angular vs direct use of the Controller/Model proxy in Ember. This makes a bit more sense to me, personally.
- clintjhill 14y ago
  Except you could write identical code in Ember as well when you extend the controller. Replace "$scope" with "content" and it's identical.
  - robconery 14y ago
    Interesting - didn't know this. $scope is injected by Angular and available to the view - is this the same thing? I didn't think Ember had a DI aspect to it.

jacquesc 14y ago

Really nice constructive writeup (as always by Rob), and I think it should be addressed by some better EmberJS docs and tutorials. They do a good job explaining the "what", but it could probably use more "why". It took me a while as well to figure out why controllers proxied to models. However it started to make a lot of sense in when building an app, since the controllers are there to stay around, and the models are swappable. Having the option to easily swap out a model at the controller level is worth the extra layer abstraction. That and the ability to add additional UI specific properties on the controller that don't necessarily belong in the model (since they don't need to be persisted).

ZoFreX 14y ago

Thanks for sharing this Rob, it was actually very informative about Ember to a newbie!

jfarmer 14y ago

I've never used EmberJS and am not familiar with any of the front-end JavaScript frameworks, but I don't get what's confusing. It looks like instead of the controller pushing data to the view, the view asks the controller for data (which it might proxy to the model). This makes sense with a long-running controller, right? On the web both the controller and view are ephemeral -- they last for just that one request -- but if the controller is running continuously then it needs to reflect changes in the models as they happen. The model(s) the controller references can change without the view changing its reference to the controller. Without something like this the view would render stale data. I'm assuming this is why we have a controller.model, to add that layer of indirection. What am I missing? How is this more complicated making the controller<->view relationship pull instead of push?

robconery 14y ago
The controller is the data. The model is grafted onto it for convenience. This ties the view to the model to the controller which is sort of orthogonal to "separation of concerns". In my opinion at least.
- clintjhill 14y ago
  The controller is responsible for rendering the view when the data changes. It does graft the model data - and any other data you want renderable into the view. I wouldn't characterize it as "the data" however.
  - robconery 14y ago
    {{#each controller}} {{name}} {{/each}} How is the controller not the data as far as the View is concerned?
    - acoleman616 14y ago
      As mentioned above, the proxied model data is actually stored in a controller's "content" field. So that snippet is actually just shorthand for {{#each controller.content}} {{/each}}

pspeter3 14y ago

Watching the peep code screen cast helped a lot

BaconJuice 14y ago
can you post a link to this?
- rizumu 14y ago
  https://peepcode.com/products/emberjs https://peepcode.com/products/emberjs

ghurlman 14y ago

Here's the Google cache: http://webcache.googleusercontent.com/search?hl=en&biw=1256&bih=787&sclient=psy-ab&q=cache%3Ahttp%3A%2F%2Fwekeroad.com%2F2013%2F03%2F06%2Fember-confuses-me&oq=cache%3Ahttp%3A%2F%2Fwekeroad.com%2F2013%2F03%2F06%2Fember-confuses-me&gs_l=hp.3...9193.10065.1.10319.6.6.0.0.0.0.70.287.5.5.0.les%3B..0.1...1c.1.5.psy-ab.Z1SKTeDnL-M&pbx=1 http://webcache.googleusercontent.com/search?hl=en&biw=1... text-only: http://webcache.googleusercontent.com/search?q=cache:http://wekeroad.com/2013/03/06/ember-confuses-me&hl=en&biw=1256&bih=787&strip=1 http://webcache.googleusercontent.com/search?q=cache:http://...

randall 14y ago

The Angular example is a bit incorrect... when you do an ng-repeat, you're going to do like ng-repeat="person in people" and then each template item will be like {{person.name}} as opposed to just {{name}}. Just a little clarity in the code. Thanks for the writeup!

robconery 14y ago
This is fixed - thank you.

ef4 14y ago

> When talking routes, urls, and resources - that's a RESTful consideration and involves stateless state "stuff" (sidestepping the REST debate here). What is this concept doing in a desktop app?. Ember is explicitly not about "desktop apps". That's actually why Ember broke off from Sproutcore. Ember is very opinionatedly focused on building web applications that are native to the web and stick to web conventions. The best web applications still behave like the web is supposed to behave: they have shareable, bookmarkable URLs that allow the application's state to be recreated. This is a big reason Ember's router is different than the other examples you mentioned -- in Ember the router automatically handles a lot more of the state reconstruction stuff.

robconery 14y ago
The team has been rather clear that Ember is Desktop MVC, not web/server based: https://twitter.com/trek/status/309315009291378690 https://twitter.com/trek/status/309315009291378690 They say as much in their guides as well.
- ef4 14y ago
  > The team has been rather clear that Ember is Desktop MVC, not web/server based That's orthogonal to what I'm talking about. I agree that their use of the term "MVC" is much closer to the original meaning it had on the desktop (like in Cocoa) than the meaning in server-side frameworks like Rails. But I'm not talking about what MVC means. I'm talking about what kind of applications Ember is intended to be used to build. A flagship example would be Discourse, which is very deeply web-focused, and nothing like the way you would structure a desktop application.
  - robconery 14y ago
    Your assertion is that "Ember is not about desktop apps". Yes, it is entirely about Desktop apps in terms of structure and approach. These apps are built on the web. One look at the Discourse Ember code and I think you'll understand perfectly the confusion I'm writing about. But I'm curious: do you use Ember or are your responses "what you think"

pixelcort 14y ago

Think of Ember controllers as proxies, or pointers if you will. The idea is you can have a commentsController instance, and when you switch to a different post, the view(s) bound to it will automatically pick up the new comments array that is swapped out on behind the controller. Routing is just rewiring the pointers on your controllers and getting the right views up on the page.

avolcano 14y ago

While I actually totally agree with the confusion in the router, I want to explain what I see in Ember's MVC: As far as I attempted to implement it in my app (https://github.com/thomasboyt/noted-app https://github.com/thomasboyt/noted-app), it seemed simple enough. Models were data; all they contained was their properties and operations that controlled their properties. I mainly used controllers as the "state" for parts of my app. In Ember, this doesn't even need to mean it's tied to a specific model type. For example, my Dropbox integration is handled within a controller that's bound to several separate views (in this case, those views included buttons that triggered syncing and modals that displayed the progress of syncing). There's no "Dropbox model," just other models that I'm using this controller to sync. Controllers are not simply an intermediary between models and views, they are an intermediary between state and views. > I'm trying my best to reconcile this with the notion that a controller (classically speaking) is supposed to ... well control the view. Here, it's not doing that. I think what the author was looking for in controllers is what's actually handled by, well, views. The view handles any user interaction, and then uses the controller to change the state of various bits (whether calling methods in the controller or simply updating properties on it). To sum up: model is data, controller is state (including instance(s) of models), and the view is user interaction. Templates can bind to properties on any of these. Routes are what hook these components together depending on the page.

robconery 14y ago
Seems reasonable, but the Ember team sees it differently... they put state in the router: >Most of your controllers will be very small. Unlike other frameworks, where the state of your application is spread amongst many controllers, in Ember.js, we encapsulate that state in the router. This allows your controllers to be lightweight and focused on one thing.
- avolcano 14y ago
  Well, clearly, they are crazy people. Nah, kidding. So they're totally right that there's a significant amount of state in the router, in that that's where you define which model and controller (and, depending on how fancy you get, what views and templates) to use on a given page. So those are essentially state. The state that can make a controller fat is essentially state that's too important for a view but doesn't need to be universal to the page. For example, with my Dropbox controller, the controller has a state property that handles the various permutations of the state of syncing (i.e. it could be doing nothing, currently saving, done saving, failed saving, etc.). This state is set by the controller on the controller, and used by multiple views to determine things like which label a progress modal should have. For example, if you had a controller representing a list, you might want to keep track of which item is selected on the controller. That way, if there are multiple views that can act on the currently selected item (for example - you might have a list item view that has a template that renders the item, and then a separate view that are buttons that trigger actions that act on the current item), they all have access to it. Plus, I always think of state defined in a router as being limited to specific pages/routes, whereas some of my controllers are used on several different routes.

mark_l_watson 14y ago

Until tomorrow there is a 37% discount on the MEAP http://www.manning.com/skeie/ http://www.manning.com/skeie/ The discount code is m137

seivan 14y ago

Wonder how many iOS developers feel home with Ember? I don't. I also do Rails, and I feel more at home with Batman than Ember.

tree_of_item 14y ago

I think the problem is MVC itself is a confused mess. It means whatever each person wants it to mean, since it's too easy to make up a bunch of reasonable sounding argumentation for whatever you want to do if you use the words model, view, and controller a lot.

agpen 14y ago
Yeah, I even wrote my own MVC framework for a small project and I still don't know what MVC is "supposed" to mean because every single implementation example I see is completely different and at odds.
chipsy 14y ago
This is the comment I agree with most. Replace a solution defined as a "design pattern" with one defined as a data structure and you get a lot more clarity. The problem MVC solves can be recomposed as "synchronization of concurrent, related, mutable data structures." The relations are definable as a DAG for each direction; the synchronization process with a cyclical graph.
- rapind 14y ago
  "Synchronization of concurrent, related, mutable data structures" is totally clear to me.
sergiosgc 14y ago
That, coupled with the fact that MVC (the classic, desktop MVC) seems shoehorned in webapps, makes me weary when frameworks tout their MVCness before stating their distinctive features. BTW, I'm much more adept of removing the controller and going to a tightly coupled stack of view-model with the use of the observer pattern where needed. Controllers remind me of that extra indirection that seems useful in design but is never really used and is thus just unnecessary complexity.
e12e 14y ago
I feel that as with many things in Computer Science, the original MVC-stuff is regrettably "under-read"[1] by a lot people. I highly recommend having a look at the various links on: http://heim.ifi.uio.no/~trygver/themes/mvc/mvc-index.html http://heim.ifi.uio.no/~trygver/themes/mvc/mvc-index.html for those that haven't read what the original model-view-controller-user idea was all about. It makes more sense from a Smalltalk/Self/Object-C/Message-passing style of object orientation ("true object orientation") than from java -- in this sense it should be a good fit for javascript as well -- but unfortunately java/c++ style object orientation (really "class-inheritance orientation") have bastardized MVC to mean something subtly different (I am not quite sure what, exactly, but I don't think I'm the only one...). [1] "Well, I'm an old-fashioned guy. And I also happen to believe in history. The lack of interest, the disdain for history is what makes computing not-quite-a-field." -- Alan Kay http://www.drdobbs.com/architecture-and-design/interview-with-alan-kay/240003442 http://www.drdobbs.com/architecture-and-design/interview-wit...

terbanator 14y ago

Your examples are incorrect. The Route's model is set as the content of the controller, so all you need to say is #each item in content. Your model is set as the "content" of your controller, so your model is not "nowhere to be found"

terbanator 14y ago
http://jsfiddle.net/sgterban/kDqBs/ http://jsfiddle.net/sgterban/kDqBs/ - Example
- drogus 14y ago
  You should use {{#each item in controller}}, otherwise you won't get things like sorting of filtering right. Yes, content is an underlying array, but controller may present it differently (filter out, sort, paginate etc.).
twinturbo 14y ago
content is wrong. You should be using controller. This works with arrangedContent. {{each content}} will not work with anything like SortableMixin.

newishuser 14y ago

Don't give up! Ember has a steep learning curve but once you've got a bunch of it memorized development gets much easier.

jonny_eh 14y ago
I learned Angular instead since it was easier to get my feet wet with it and seemed to make sense to me. Am I missing something by not using Ember?

jhysum 14y ago

Instead of controlling the view directly from the controller, the view uses the controller object (proxy to model) in any way it wants allowing you to change the view without changing the controller and same with the controller. I think the issue you are facing is thinking that you are tightly coupled to the controller by using the controller object, depending on what you think about how much coupling is too much coupling you can argue that just using one object might really be decoupling. I'm not sure if I was able to get my point across.

Tichy 14y ago

I think the way controllers work here is similar to Ruby on Rails? It confused me in Rails at first (coming from the Java world), but I think it is essentially just a hack to allow for "easier" passing of data to the view (the controller gets exposed to the view). So instead of scope.whatever = "hello world" you can write this.whatever = "hello world" (OK not really shorter, but something like that). That usage of Controllers is not part of the MVC pattern, I'd say. It's just a recycling of the controller instance - not forbidden, just confusing if you wonder what it has to do with MVC. Actually it's also the RoR way to have short lived controllers (a controller is instantiated for every request), other frameworks use one static controller instance instead.

anarchotroll 14y ago

Seems like the big confusion about the controller is that it is closer to a ViewModel (think MVVM) than to a Controller itself. Potatos, Potahtos.

mcgwiz 14y ago
That's the hunch I had reading this (as someone with no EmberJS experience). To digress a little, it's not much different than the terminology confusion in Backbone, where: - Router(s) work as front controllers, - templates (along with the browser's DOM) as views, and - Views as presenters (from the MVP pattern). Models are flavored with the Active Record pattern. Presenters and views are tightly coupled. MVC and MVP coexist because the controllers respond to navigational input (mapping to model-presenter pairs) and the presenters respond to page-specific input (mapping to model manipulations and, possibly, server calls).
Kiro 14y ago
Model, View AND ViewModel? What kind of confusing terminology is that? I use KnockoutJS but I still don't understand why it's not just called MVC.

devinrhode2 14y ago

At first read, I thought your point about routing was really good - why not have route('about').template('aboutTemplate').controller('aboutController') - and then I realized this is all reapeating the same mumbo jumbo. This is all automatically matched up by the naming convention (which frustrates me too, but until I figure out a better way...)

andreipop 14y ago

Take a look at Yehuda's talk from Seattle: http://www.youtube.com/watch?v=4Ed_o3_59ME http://www.youtube.com/watch?v=4Ed_o3_59ME - I think it explains a few things very well, and helped me out a ton

sandstrom 14y ago

Although really old (and outdated) I found this Sprout Core introduction useful. The first 3-4 minutes was enlightening for me. http://vimeo.com/24487742 http://vimeo.com/24487742

tonycoco 14y ago

Curious for yourself? Try following my simple starter app tutorial of Rails + Ember.js here: http://www.devmynd.com/blog/2013-3-rails-ember-js http://www.devmynd.com/blog/2013-3-rails-ember-js Though, I understand the pain of coming from a server-side MVC architecture, I found it refreshing that Ember.js takes the "desktop" MVC approach. Our web apps are now living on the client, acting like desktop apps. Most people struggle with this reverse at first, but can conceptually catch on if shown the way. I think what really needs to happen is a good screencast or two walking through these concepts. I'm interested in putting something together and will when I have the time.

tmzt 14y ago
While there is quite a deal of information on integrating ember-data with rails, there is much less on integrating it with other server-side MVC/REST frameworks. This means that using it with another framework often means modifying that interaction pattern to be more like how rails views ajax, complete with the root objects ({"model":{}}). This may more accurately apply to the REST driver in ember-data, but that is quite tightly coupled with the rest of it.
- tonycoco 14y ago
  That's def a job for the adapters. Django, for instance, has a REST adapter that has been worked on here: https://github.com/toranb/ember-data-django-rest-adapter https://github.com/toranb/ember-data-django-rest-adapter As far as the root objects are concerned, I've always been a fan of that part of Rails. Not to say that it cannot be easily gotten rid of with something like this (for ActiveResource)... ActiveResource::Base.include_root_in_json = false Or, like in my example app, with this (for ActiveModelSerializers)... https://github.com/rails-api/active_model_serializers#1-disable-root-globally-for-in-arrayserializer-in-an-initializer https://github.com/rails-api/active_model_serializers#1-disa...
ffreire 14y ago
There seems to be some very positive buzz around this screencast mentioned both in the OP's blog and around HN in general: https://peepcode.com/products/emberjs https://peepcode.com/products/emberjs . I found it particularly instructive but found that it only scratched the surface of this new framework. At least, it scratched enough off the top that I feel comfortable rooting through source and API documentation to figure out the rest. YMMV, of course.

sideproject 14y ago

I come from Backbonejs background with which I have worked for about 1.5 years. So I feel quite comfortable with it. I decided to try Emberjs - not for any other reason than trying to pick up something else and see how other JS framework approaches. I gave full two-days worth of time into it. Initially I thought - "How different can it get?" Plus, I believe even if it's very foreign I'll just keep reading, googling, stackoverflowin', youtube-tutorialin' to get my head around. I gave up though. Here's my hopefully constructive rant, though my views are probably not as deep as the OP's. * Many of the posts on the net are outdated. I followed a few tutorials here and there, and then things didn't work, so I asked on Stackoverflow, then the answer I got was "Dude, your code is outdated". Sure this is probably similar thing for other frameworks - but I'm just sayin' * Models - So there is Ember Object, which you can use as models, but you can also use Ember-data.js which is more "glorified" data. Documentation wasn't clear on the difference. Plus, Ember-data.js was quite hard to get started with. It didn't work well with other versions of Emberjs. I really had to dig in to find the right one to start off with. I ended up cloning a github repo of a tutorial that worked, because nothing else did. * Documentation on "convention over configuration" - OK, so convention over conf. is fine. But the official documentation and many of the tutorials didn't explain what all the conventions there were. I went through a tutorial app, which only had Controller, but things just "worked", because the Emberjs builds all other things for you. Well I didn't know that! THE BEST INTRO EMBERJS VIDEO I found was this. http://toranbillups.com/blog/ http://toranbillups.com/blog/ It finally made sense in the end for me. * But in the end, among all other things I wanted to do, I gave up, because the frustration was mounting up. I guess I can still persist through it. But I just finished AngularJS tutorial demo and in 2 hours, it makes sense to me.

rxcfc 14y ago
The Ember teams has been planning for a sweep of all outdated information about Ember. We'll be updating SO questions and asking blog authors to add a disclaimer. Ember Data is a completely optional component of Ember that seeks to bring ORM-like abilities to the client side. It's not as far along or as stable as core Ember. For what it's worth, you can easily just use jQuery.ajax and create Ember.Objects from the response. We probably do need better documentation in this area to make this clear. That said, it's not fair to count Ember Data as a point against Ember since no other framework has anything at all similar in scope. Our overview documentation is lacking. This is something that we're actively working on improving. The hardest part for new developers coming to Ember is that the paradigms are very different than what they're used to. We believe that the paradigms are the correct ones, but we need to do a better job explaining them.

tericho 14y ago

I'm by no means an "expert" but I shared the same struggles and after 2 weeks of trying to build a complex app I gave up. I switched to Angular (which I also had never used before) and got the same app up and running in a couple days with even more functionality because I was able to hash lots of the trickier "outside-the-box" functionality that I could not for the life of me get working in Ember. That being said I really like Ember's syntax, Handlebars integration, core values (performance & stability specifically) and have the utmost respect for its creators. I'm hoping since it hit 1.0 that lots of new sample apps, blog posts and SO-type Q&A resources will start showing up and actually stay relevant for more than a month.

nirvanatikku 14y ago

+1. you hit the nail on the head and articulated what I was feeling when I played with ember.

richo 14y ago

> I think Yehuda is a very nice and smart person I always get confused by this. I don't understand how being nice factors into technical decisions? (For the record, I also think wycats is nice, but I don't really care when I'm trying to decide whether or not what he's saying makes sense)

rcourtie 14y ago
I assume it's to say that he doesn't have some sort of vendetta or dislike of Yehuda that's coloring his opinion.
davidw 14y ago
If you need help, want to suggest a modification, or otherwise need to interact with the author(s) of something you're using, it's nice to have friendly people to deal with, rather than assholes, all else being equal.
- richo 14y ago
  I hadn't thought of it that way.

stevewilhelm 14y ago

> Ember is explicitly not about "desktop apps". That's actually why Ember broke off from Sproutcore. Ember is very opinionatedly focused on building web applications that are native to the web and stick to web conventions. This may be the issue. I think most of us never really wanted to build web applications, but we were forced to do so due to browser and framework limitations. We really just wanted to build the best damn desktop app possible that just happened to be deployed in a browser via the Web. This might explain our confusion and disappointment when client side frameworks don't deliver on that desire.

rxcfc 14y ago
Are you implying that Ember doesn't deliver on this desire to build desktop class applications in the browser? If so, can you explain where it falls short?
Pherdnut 14y ago
Most of whom? I came up in JS on the client-side. Nothing has been more frustrating over the years than watching all of the inflexible bloat and tightly coupled BS people have been piling on to the client-side in order to pretend it was something that it is not. Web forms sucked ass. Everything Java tried to do to pretend the client-side wasn't there has left massive legacy potholes all over the web. Just deal with the thing as it is already and learn something new. You're a programmer for chrissakes. I might indulge in writing OS apps with webkit but I don't try to add a server to the process if it's just a local desktop app in order to make it more like what I'm used to. HTML, CSS and JS properly applied are doing 4/5ths of what these frameworks are pointlessly reinventing. All you have to do is learn them properly. The rest, keeping data loosely coupled, is basic 'duh' OOP. All the stuff that's already there works surprisingly well if you actually give it a chance. Or have you not noticed that web technology solutions are spreading like wildfire into other domains or that we can implement and modify GUIs using client-side-web-technology a lot faster than desktop OS UI developers have ever been able to? FFS, they don't deliver on that desire because it's proven time and time again to be a complete waste of time to try to.

BlindRubyCoder 14y ago

The whole point of EmberJS confuses me.

gavanwoolery 14y ago

I have not used Ember, but you mention MVC, which immediately brings to mind Sencha. I have used Sencha a lot, and although I think it is mostly great, I do not like how they try to pidgeon-hole you into the MVC methodology, which just does not make sense in many contexts.

selvan 14y ago

I tried Emberjs and Angularjs recently, as both framework offered two-way binding between view & model, at client side. Angularjs was easy to pickup and I have completed what I wanted to do in about half a day, except one issue, angularjs template rendering is DOM driven. I wanted server-side templates, hence I have to boot phantomjs at server-side. I didn't quite like booting phantomjs for server-side templates. Since Emberjs offered, handlebar based templates, I was happy that I could render my templates at server-side. So tried emberjs, it took about 3 days, to get it done. Many out dated tutorials & documents spread across internet about older versions of Emberjs. Documentation at emberjs.com is minimal and not helpful. I started looking at source code of discourse.org and try to understand how they used ember. I felt the power of emberjs when I needed complete control of context and rendering of nested templates. It was real beauty.

deleted 14y ago
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Kiro 14y ago
In what circumstances would you want server-side templates and how come it's easier with Handlebars?
- davedx 14y ago
  SEO.
  - e12e 14y ago
    Not only SEO. If you need to build a webapp that is also a web page (eg: blog, wiki, cms) -- you want a rich client, but also relatively plain pages -- and ideally you want to share code/templates where it makes sense.
    - masklinn 14y ago
      Also to improve "bootup time", from request to usable: server-rendered templates can be cached, can provide at least visible content before javascript even has to run and can use beefy servers & the like. At that point the client "only" has to do the events binding wiring and it's done.

fcatalan 14y ago

Ember confuses me too. I've worked with many server and desktop MVC frameworks for almost 20 years. I'm familiar with MVC, it plays simple and easy, like rock-paper-scissors. My problem with Ember is that it seems to be more like "rock-paper-scissors-lizard-spock but for us the rock punches through the paper and the scissors cut the rock like butter. And you can play without actually showing your hand". Confusing.

pradeepin 14y ago

Yes, I too agree EmberJS always a confusing library, Following are my resaons. 1)They say it follows MVC. Its actually MVC but MVP, if you look closely at the implementation. 2)Controller job is not precisely defined. Example: Even the data validations are done at controller level not a model level So i switched to Backbone.js, which is very flexible library with tons of plugins that can be used when needed. Since implementation of UI is different from requirement to another requirement. I feel EmberJS doesn't satisfy this, which leads to people using Backbone.js. Regarding AngularJS, please use it only if you are new javascript and prefer learning Angular Javascript (which is not javascript by the way) :)

ganarajpr 14y ago
Regarding AngularJS, please use it only if you are new javascript and prefer learning Angular Javascript (which is not javascript by the way) :) I am not sure you "know" javascript. If you are saying that there is an Angular version of javascript then you are terribly mistaken. Angular is probably one of the only mainstream framework that stays true to javascript. All other frameworks ( Backbone, Ember etc.. ) are the ones that actually mould javascript into an OOP language. I would say that Angular uses the prototype chain ( you know javascript is a prototypical language right? ) the best. The whole scope object inherits prototypicaly while in all other frameworks we create an illusion of OOP. Someone correct me if I am wrong here. Just for clarity, I believe that when you write Angular code you are writing the purest form of javascript. Because thats what you are writing there. Just plain javascript. There is no constructs imposed by the framework at all. This is probably why most people think "Angular's javascript" is not javascript. They have been always fed layers on top of javascript because "javascript is somehow not optimal, not right" and it has to be "changed" and "corrected" . OOP is shoved down the throat. This is probably gone on to the extent that when someone actually writes in pure javascript it starts looking like a foreign language !!
- WickyNilliams 14y ago
  Before berating other people's knowledge, you should probably make sure that what you are saying is infallible. So with that I ask you: Do you realise that JS is an object oriented language? Prototypes are a means for inheritance (i.e. reuse of code), just as classes are in more traditional languages - it does not mean JS is not OO. My interpretation of the GP comment is that he means angular to JS is like jQuery to JS, it's effectively a DSL that you have to learn in itself. Someone once said "people don't write javascript anymore, they write jQuery". That's what I think he meant

xmlninja 14y ago

You are not alone.

jondot 14y ago

In the past I've been working on enterprise application suites for the desktop. The kind of monstrous applications that run on electronics manufacturing floors. Such a typical application has a shell, modules, inter-module communication, dynamic module loading, plugins, and much much more. One can think of it as Eclipse with its ecosystem. To build such a system on the Enterprise with its typical NIH (not invented here) paranoid attitude was VERY hard. I had to reinvent a lot of wheels. On the Web, I've used backbone for a long time now, since almost the time it was out. I saw the same problems building complex applications with it (that backbone-marionette amends to a great deal). For a larger project, I evaluated Angular. Had very strong negative feelings about it. Then I tried Ember. It took me a long time to "get" it. The only thing that kept me motivated is knowing that Yehuda, Tom and Trek and other capable people are contributing on it. I kept fighting through the outdated tutorials, the outdated videos, and even the peepcode video was embarrassingly confusing to me at some point. But then it hit me. Ember and its infrastructure, the way its MVC is rigged, was very similar to what I was building from scratch on the desktop many years ago. It truly IS the one framework that "gets" desktop, or client-side, applications. The causer of my confusion was that I didn't completely let go of the "Web-think" for building application. I was stuck at either server-side MVC (MVP), or bare-bones frameworks such as Backbone. It's been just too long out of the real complex desktop game for me, to realize what that I'm looking at is a proper MVC framework. So for me, Ember ended up as being great - it still takes me back to the way I was building desktop applications, and I'm sure it will become even better and better. To understand it, you need to cold-boot your thoughts into that classic desktop MVC place; and if you were never in it, I think Ember is an excellent way to get into it as opposed to other frameworks.

itsbits 14y ago

I have been into MVC frameworks for 4-5 months now...mostly used BackBoneJS before switching to EmberJS..conceptually I did felt EmberJS very tough in the beginning..i was worried whether i made the right choice in using EmberJS for my product..but now with the latest 1.0rc2, its so easy in development..routing has been improved very much..Binding is the awesome feature i liked and helps me thgh..an added advantage over BackBone...i cant say about angular..but am quiet happy with EmberJS...

melc 14y ago

i've been using ember for the past three months in a fairly complex project and i'm very happy with it ; a platform that builds business web apps dynamically for devices (20+ pages,250+ fields per app with validations, calculated fields, conditional flows etc , rendering/theming in jqm -> packaged with phonegap) and client web browsers (render/theme in bootstrap),the backend is in java. So, i certainly don't feel the same way for emberjs as the writer. I had decided to build the frontend in a js mvc framework and the candidates were backbone, emberjs (pre version), angularjs. Read about them and gave backbone a try, however from the documentation only emberjs approach felt better maybe because of a similar in-house development java framework that we work on. So i tried to give emberjs a try at the same time, due to the tight deadlines. I dropped backbone, and spent more time on emberjs because everything simply worked and fitted together nicely. All these binding mechanisms are great and actually work :) . Haven't tried angularjs. The system now works with emberjs (pre and rc) with a nice layered architecture and separate independent business logic modules. My advice is to read the documentation carefully and choose what fits better to your needs and coding styles.

nXqd 14y ago

The only reason is you are in love with AngularJS. I will find someone who really hates angularJS because if we have a lot of validation, it will become a messy of ng-*. So no matter which framework we use, we should talk about real world project. Not simple usage that only exists in trying and testing. Use the framework, you love and you will make it beautiful no matter what :D

jonascopenhagen 14y ago
> I will find someone who really hates angularJS because if we have a lot of validation, it will become a messy of ng-* Are you talking about HTML validation? AngularJS supports using data-ng-* which means it's valid HTML.
ebiester 14y ago
At this point, you write a directive. Your directive should be watching your model and adjusting as appropriate, rather than trying to fit everything into the provided.

sudhanshu80 14y ago

We have applied EmberJS to a fairly complex application backed by Rails backend. We had to deal with complex JSONs delivered by backend which were schemaless MongoDB documents. At lot many places we had non RESTful Rails controllers. So when we started with EmberJS we had a worry the documentation was not proper, there were very few reference projects. After a few weeks of thrill and steep learning we settled on with things. We have applied a lot of functionalities offered by Ember to our code. Migrated from router from old to new api of pre 4. But we feel in our team it was right thing to apply Ember. The way overall MVC imposes structured programming, the way HTML is seperated from JS, the way ember data can have serializer and adapter customized, two way bindings all of it had been useful. We struggled at few places with deep nested JSONs in hasMany/belongsTo relation in embedded JSONs. But doing workarounds were easy. We used fixtures to hasten development while backend was not yet ready. All in all we believe that we made a good choice to stick with Ember, though it looks difficult to comprehend on the start but thats also getting better with time.

visarga 14y ago

I just think the basic idea is to keep things as separate as possible, to keep complexity down. Just encapsulate things OOP-like, hide the guts, and provide a clean access API to them. That makes it manageable.

Pherdnut 14y ago

I'm confused by all of these MVetc... libraries. We had routing behavior to content/views covered already. How is anything that does more than help isolate/manage data more than cruft in regards to having some sort of MVC-but-not-really-style-app on the client-side-web? IMO, it's all just pointless abstraction of the type that JS devs should have learned to avoid from observing server-side fail over the years. What really blows my mind is the number of these frameworks that embed pointless behavior dependencies directly in the HTML and act like they're doing us a favor. That's awesome, now we're back to changing things in multiple places to make adjustments to our apps that used to happen in one place following basic "duh" best practices that the authors of these frameworks don't appear to have ever understood properly. HTML is the router you saps! Hell, how about we add pointless-in-a-language-with-first-class-function IOC fail, config files and pointless dependency management as well? Wait WHAT!? ARE YOU !@#$ING SERIOUS!?