Combining Ruby on Rails and Backbone

I was wondering this for quite a while and haven't really found an answer for this yet.

Why would you use Backbone.js exaclty 开发者_运维问答inside a Rails application? Is it to extend functionality, have a more MVC pattern for your JS, build better API's...?

At the moment I can't see a reason why you would want to use it for something, because I don't think I understand the concept of Backbone.js

The big advantage of rails is that you have one platform and one language that you use that will handle the server-code and can generate the client-code (using the views).

Undoubtedly this theoretical advantage quickly starts slipping once you want to improve your user-experience with javascript and jquery. So actually you still have to learn two languages.

But still: all your models, business-rules, ... is handled on the server-side in Ruby. This also means that the server always has to be reachable.

What a javacript/client MVC (like Backbone.js, Sproutcore, ...) can offer you is a more native application feel. A single web-page application, like e.g. Gmail. Depending on your requirements there are some very valid use-cases for such a platform. E.g. in places or devices with low connectivity it could be very useful (with HTML5) to have a web-application that does not need to be "online" all the time. It could save data and edits to the local storage and sync back to the server/database when the device is back online.

But, there is a big disadvantage when developing client MVC applications in combination with Rails: you will have to do some double development (it is the same when you are using flex/silverlight). Your models will need to be defined both on the server and on the client. I can imagine that some improvements could be made, like on the client MVC you are actually using presenter-classes, which on the server-side could be stored in different models/tables. But still there will be duplication of logic, models, ...

So that's why I think that for most applications, at the moment, it is not wise to switch to some client MVC framework. It will be a lot more work.

But when you do need the look and feel of a real native application, or a one-page-web application, then a javascript client MVC framework is the way to go. And if you do need a client MVC framework, I would propose Sproutcore.

To simply ajaxify your current rails application (reduces load-time of every single page), take a look at pjax-rails.

(better late than never - hope this is useful to someone) The description on backbonejs's website seems like a lot of words thrown together without much meaning. There is a big hype around it but what's all the fuss about?

The premise behind backbone is that modern day, single page web apps (think gmail) quickly become a very complex interaction between syncing dom elements, UI events and the backend. You could easily find yourself storing data within the dom elements, and then having to somehow extract the data again to update the database. If you don't structure your code very carefully, you'll quickly end up with spaghetti code full of complex bindings, or code without backbone.

Using backbone's models, collections and views gives you a well thought out structure to work within, allowing you to build large apps without being overwhelmed by their complexity. What's more, it ties in beautifully with a restful backend.