I just recently got introduced to MV* frameworks and have taken a chance to try out Ember.js with the TodoMVC app tutorial they have on their site.
I was considering using Ember for one of my upcoming projects (a Ruby on Rails CRUD app, similar to Twitter in some of the functionality), but I'm still a bit confused and before I take a final decision I would love it if somebody could clear the following concerns:
Is it a good idea to use such an advanced framework as Ember for a medium-sized multi-page CRUD app? Will it improve development time and maintenance compared to an interactivity layer built with jQuery's DOM manipulation and AJAX capabilities? Or is using Ember (and the like) only good when developing complex single-page apps (e.g.: Grooveshark)?
Considering the app will be developed using Rails, and assuming Ember will be used, is it going to be possible to offer a fallback with basic functionality for browsers with JavaScript disabled and/or for search engine crawlers? Will it require code duplication or other dirty tricks? Do you know of any technique that can be used to achieve it?
Will it be possible to adapt the website for mobile browsing (using only CSS) with valid results, or will the overhead imposed by running Ember on the phone make it hard for the device to render the website in a way that keeps it responsive?
We're in the middle of a pretty big Ember project right now, so here are my thoughts on your questions.
We've found Ember to be really productive for creating rich UIs for our single page app, but I don't know that it's going to be that much more helpful if you're creating an app designed for traditional multi-page (viewing pages, submitting forms, etc) layout.
I think this is the clincher - Ember is completely JS-based, so if you need to support browsers without JS, you'd basically have to write a parallel application. If this is a hard requirement for your app, I think Ember (or any MV* JS framework) would be out of the question
We've had very few performance issues on mobile - our site is fully responsive and renders on everything from Blackberries to the latest Chrome on desktop with good performance.
#Scott Rankin, has addressed most of the concerns with going with the Pure Ember approach. I'll add one quick way to make this decision.
Go with Ember/MVVM if the application is behind a login. Then you don't have to consider search engines, as the content is generally private and not supposed to be indexed.
For SEO you have to build atleast part of your content such that it is indexable. A good example of this is the Discourse application. They use Ember but also send down some generated html along with the app html slugs, so that search engines can index them. You can read about their approach here.
We have a different approach which can be seen as a fall back: We pre-render a static version of each page in the application (daily scheduled task). This static version is stored on the server as HTML file. Whenever we sniff as spider/ robot user agent, we deliver that version.
Related
I'm currently developing a Single Page Application (in this case AngularJS), but as it grows I find it more and more tempting to refactor it into a multi page app.
However, I still need the ability to have sophisticated, dynamic UIs on the client (which requires more than just DOM manipulation but awareness of my information model).
I know most people use jQuery for this; I'm afraid it won't get me as far as I want, and I'm wondering if ReactJS is suitable for that job (well, when you're running a small company, not Facebook).
To be quite honest I've tried the single page app route with Angular, Backbone and even Knockout to an extent.
In my efforts I've found the most maintainable solution, especially for large teams is to use a multi-page app and rely on React to create a dynamic single page type experience where it's necessary.
Due to the buzz term SPA I've found a lot of teams think they need to be cutting edge by adding unnecessary complications like an SPA where a standard multi-page MVC app is a much better solution.
To me, React is the perfect solution for the problem of building a large scale website which may act as a multi-page app in some areas where necessary, but use standard sane MVC elsewhere.
React just works very easily with Django, ASP.NET, Ruby etc...
I'm about to embark on a large project based around mobile web apps. I am going to create a mobile web app that will have multiple screens, a search system and a few other features.
I need to establish a primary framework for this application. It seems I have two options; multiple separate HTML pages, or alternatively, use AJAX to download the contents and move divs in and out of the viewport.
I don't have to worry about SEO. I'm primarily looking for good performance. I understand Stack Overflow is a site about questions and answers and this does somewhat involve opinion, but I feel that based on my criteria there should be a solid answer to this question.
I'd highly appreciate it if somebody could share what they think the best option would be for me on this project.
What I believe you're referring to by using AJAX to download the contents is commonly known as a single-page web app. These generally involve rendering data using templates on the client side and sending and receiving the data via AJAX.
For these, there are plenty of excellent JavaScript framework options, including:
Backbone.js
Knockout.js
Angular.js
Ember.js
Of these, Knockout is probably the easiest to learn (seriously, the tutorial is brilliant), but the lack of routing lets it down somewhat. I tend to use Backbone for this type of thing myself, although if I were starting over I would probably go for Angular as it's made by Google and seems to have more momentum. But try a few tutorials and see which one works best for you!
All of these offer a lot of very handy functionality for your use case, as they enable you to load data via AJAX and render it on the client side quite easily. There is a learning curve for all of them, but they result in a much more maintainable and testable client-side application. Believe me, I have tried to build such an application with just jQuery, and I would recommend you avoid it as it gets very painful, very quickly!
Your mileage may vary, but by and large a single-page web app like this should perform better than a more traditional web page because once the application has loaded, all the communication with the server is just sending and receiving JSON. It will also likely be simpler as you can use a lightweight REST framework like Slim, Sinatra, Express or Flask on the server side, and just serve up the static content on the home page, then do everything else via AJAX.
I'd like the perspective of more experienced programmers on the place and use of an Ember.js app.
Initially, I thought Ember.js would be similar to Express, Rails, or CodeIgniter in that they are full fledged frameworks for developing content on many pages.
However, the more I delve into Ember, it appears that it is designed for apps on a single page where the content can change dynamically due to the user's interaction (due in part to a misunderstanding on my part of what a single page app is).
Am I correct? And what are some good examples of sites/apps built with Ember.js?
I've used it for building two full enterprise SPA, one backed by django-rest the other backed by web-api. They are completely Ember, not just web-components etc.
That being said perusing through the Ember users will give some fun examples http://emberjs.com/ember-users/
Discourse is one of the bigger fully fledged sites built with Ember, they've been at it for a while.
I have come accross an sample application with dojo 1.5, but it's not really what I want to achieve : it is not modular at all. I want to make use of the amd, and various design patterns (like MVC) to have a very organize application. Unfortunately, the dojo community and "example" are not quite visible or present (compare to Jquery). There's a lot of cool tutorials on various implementation of specific dojo features, but none that's explain the very basic on how to create a simple (but at the same time, complex) squeleton for a dojo project. I came across the dojo boilerplate project on github, and tried to start from there, but I find it really hard (as a beginner) to implement such trivial things such as an login or basic interface (and separate all that by module, event handling, data, etc.). I just don't want to make a dojo application by using only an index.html and one javascript file, I could do it, but for maintenance and adding stuff, it will just be a complete mess. With this post, I hope to gain some information on this specific subject and perhaps create a tutorial for dojo on how to start up a real web application. For example, applying the mvc pattern, I think a good application tutorial should have a login example (authentification) and a basic modular interface (like some kind of main container, and on various events, the container ui change for instance with different widget). I'll be working on something on github and posting up when I'm done. If your done before go ahead ;)
thank you.
There is TodoMVC at GitHub:
a project which offers the same Todo application implemented using MV*
concepts in most of the popular JavaScript MV* frameworks of today.
It employs dojox.mvc #PEM mentioned. It's not a typical way of building Dojo applications as dojox.mvc was released just on May 16th, 2011, but it is worth looking at. There is also live demo and tutorial Creating Todo MVC in Dojo:
Overview
Part 1: Models
Part 2: Views
Part 3: Controllers
Also have a look at the source code of Dojo Web Builder (+ article Introducing the New Dojo Web Builder).
Last but not least is Maqetta (sources at GitHub), the most complex Dojo application one can find. Look esp. in maqetta.core.client/WebContent/ directory.
Maybe you have not searched enough?
Dojo MVC :
http://livedocs.dojotoolkit.org/dojox/mvc
http://dojotoolkit.org/documentation/tutorials/1.7/data_modeling/
I just don't want to make a dojo application by using only an index.html and one javascript file
But that's basically what Dojo is for and good at...
If you just want to make cute animation on a plain old html website, rather go for jquery, it's sexier.
Now if you want to do a "real web application" then dojo is the right framework. But you'll also have to learn how to use it.
There are a couple issues with building a sample application tutorial.
First, a sample application with what you have described will need a web server to communicate with. Dojo is web server agnostic, so what technology do you choose to for the sample application? Secondly, a server is now required to make the demo available online, or the person interested in looking at the demo would need to install the web server. As simple as this sounds, it is a barrier and prevents a more novice person from continuing.
Second, even with a web server there are many ways to build/architect a web application.
I think a good application tutorial should have a login example
(authentification) and a basic modular interface (like some kind of
main container, and on various events, the container ui change for
instance with different widget)
From what you have posted, it reads like you are looking for a single page application. There are downsides to single page apps (such as SEO) and creating a sample single page application needs to make it clear to the developer what the downsides of using the sample are. It's not the magic bullet for all Dojo/Web applications.
I have a project up on Github and it certainly isn't ready for primetime, but you can take a look. This is a Single Page Application that uses Java/Spring for the backend server. I am a couple days away from checking in the Spring Pet Clinic example which will demonstrate some of the functionality. I also need to update the wiki to describe how to create a sample application.
https://github.com/cswing/evinceframework
Also, I use the theme tester often to take a look at different widgets. Not entirely what you are looking for, but some who get to this question may find the link useful.
http://archive.dojotoolkit.org/nightly/dojotoolkit/dijit/themes/themeTester.html
I would like to know, how powerful/viable are JavaScript only clients based on say, GWT/gxt/vaadin, when compared to DHTML clients such as those made with wicket, tapestry, click etc?
My boss has insisted on using GXT (due to its nice colors and theme) on a project that will most likely become very big with lots of screens. I am against the idea of a javascript only client, especially when the javascript is generated from Java code. I have tried to advice him that we use something like wicket whereby we construct the screens with html but put in ajax where and when neccessary.
How viable is such a JavaScript client? I understand that JavaScript was intended for minor web page enhancements, and not all browsers, especially mobile devices have complete support for JavaScript.
Yes, it is viable for certain applications. Consider Gmail, Google Docs and Google Maps as typical applications where this works, and is probably the most feasible approach.
Some rich UI JavaScript frameworks, such as Ext JS also rely on this technique.
I've built javascript only web apps for ages.
First in SAP projects for big multinationals. And now on a new project:https://beebole-apps.com?demo
So yes it is powerful and viable.
Javascript-only webapp can be extremely powerful, and it's viable for certain applications, say, an Instant-Messenger webapp?
You mentioned that there are lots of screens in your web-app. One of the advantages from GWT/GXT is the fact that you can unit test your UI-layer with JUnit. This is an extra testing you can do on top of, say, Selenium. This is essential if you'd like to make UI testing a part of the continuous integration process, and, as the team grows, you'll definitely want to have tests around to make sure everything works (At least in theory.)
However, if what your boss meant to do is to build an in-house, custom Javascript engine using GWT's JavaScript Native Interface (Link), then I'm not sure...
Another advantage with GWT-like-engine over Wicket is that you can rely on HTML-code-gen to generate standard-compliant (In theory) HTML code. With framework like Wicket, it is hard to ensure every single developer on the team to author good HTML code - Especially when the team gets bigger.
Disclaimer: I'm a member of the Vaadin team.
Our Timeline demo is a good example of what can be achieved with Vaadin and GWT in client side, but I think all of the options presented in this discussions are viable given enough time.
Since you are going to start a big project you should build a simple proof-of-concept app with each of the relevant frameworks. If your PoC includes at least some of the more complex use cases you'll probably can make a pretty informed choice based on the experiences you get while building them.
I urge you to at least evaluate Vaadin. With it you write only server-side Java code and Vaadin will create a slick and professional browser UI for you. Client side can be easily extended using standard GWT (also pure Java), and there are no HTML templates, tag libraries or XML configuration involved at all. A Vaadin UI is fully Ajax'ed and lazy loading out of the box, and it easily integrates with any server side technologies, eg. Spring.
In addition to the development model advantages you get top-notch documentation, a bi-weekly update schedule, a very lively community filled with helpful experts, 100+ useful open source add-ons, and a 10 year old backing company with help on hand should you need it.