Question

I’m getting my data from a service and then setting the data to my bean object and want to using the same data in my view displaying it in a form in rails view now. Now I want to validate this form using backbone.

I’m new to both Rails and Backbone.

Kindly give me an idea on how to proceed on this.

Answer 1

I think perhaps you are confused about how web applications work. Backbone is a client-side framework; it uses Javascript code that is run in your users’ browsers. Rails is a server-side framework; it uses Ruby code that runs on your server.

Given all that, your Backbone code and your Rails code by definition have to be completely separate. The two can communicate in only two ways:

1) Your Rails code can write <script> tags to the page (inside a .html.erb file) and put variable data there; for instance:

<script>
var myVarFromRails = '<%= someRailsVariable %>';
</script>

When that comes back from the server (ie. when you view source the page) that will get converted to:

<script>
var myVarFromRails = 'foo';
</script>

(assuming ‘foo’ was the value of someRailsVariable).

2) Your Javacript code can make AJAX requests to Rails URLs, and whatever the Rails code spits out there will come back as the response to your AJAX request. In other words you can do:

 $.ajax({url: someRailsUrl, complete: function(response) {
      // whatever the server sent back will be inside the "response" variable
 }});

Other than that the two are pretty much entirely separate, and if you want to do the same thing in both of them (eg. validate a form) you essentially have to write the code twice, once for Ruby and once for Javascript.

I say “essentially” because there are Rails plug-ins which do #1 and #2 for you in different ways. I’m not a Rails expert, and even if I was there are so many of these plug-ins that you really need to look for yourself to find out what exists and what makes sense for your codebase.

Hope that helps.

* EDIT *

I know I just said I wouldn’t list libraries, but then I realized it’d be more helpful if I at least provided a few to get you started. Just don’t take these as canon; they’re simply some popular libraries at the moment, but they may or may not be right for you.

1. https://github.com/codebrew/backbone-rails
2. https://github.com/meleyal/backbone-on-rails
3. https://github.com/aflatter/backbone-rails
4. https://learn.thoughtbot.com/products/1-backbone-js-on-rails
5. http://kiranb.scripts.mit.edu/backbone-slides/

That last two aren’t actually libraries, they’re a book/presentation, but I thought they might be useful.