Question

I’m thinking about this since a while: I’m build a single-page webapp with ExtJS library.
The whole GUI will be handled with JSON through AJAX requests, so I effectively never use the view functionality (except for the main page, where the view is six lines just to write basic tags).

However, I struck in a problem which I think will happen often during my application: I have a complex json which needs a lot of view helpers to be built, expecially for referencing other resources like images. These json objects are statically written by me, for example I need to configure ext to render some desktop-like icons which needs title and a reference to an image. I think this should be written as a view where params are an array of hashes containing title/image.

That being said, I were thinking about an approach where my json objects will be built by the view, and not by the controller as I’m currently doing.

My questions is:

Is this approach OK? I feel like violating MVC pattern when I try to use image_path helper inside my controller.

It’s important to understand that I’m not trying to fetch something in the view, I’m just passing some model objects as params to views and write them in a json fashion. I can’t (always) use .to_json method because sometimes I need to organize those json objects in a totally different way.

Edit 1:

I’m adding a small question that could become really useful with this approach: is possible to parse (in the controller) a YML.ERB file in the controller but allowing it (the yml) to use all those nice helpers that I have in html.erb files? I would like to use them because is nicer to build some static json objects in yml rather than plain json. If that’s the case, how to do it? Remember that I’m in a controller. Thanks a lot.

Answer 1

You can easily write json directly in your view templates, just like you would be writing erb, or xml. E.g. if you have a controller like this

class FoosController < ApplicationController
  def index
  end
end

And you accept format in your routes, then you can simply create a view

<% # app/views/foos/index.json.erb %>
{ some_json_stuff: "<%= link_to 'home', root_url %>" }

This view will be rendered when you access /foos.json. This enables you to write any custom json with helpers, partials, etc.