Where can I store site-wide variables in Rails 4?

Question

I am new to Rails and come from a ColdFusion background, where we would store global / site-wide variables in the \'application\' scope. This persists the variable across an

Answer 1

This sounds like a perfect example for configuration values stored in config/environments/production.rb and config/environments/development.rb. Just store any value there:

config.my_special_value = 'val'

And access it in your application like this:

Rails.application.config.my_special_value

Always the value of your environment is active.

If you just want to have a „global“ value, store it in your application controller. All your view controllers are derived from your app controller, so you can save any value there as an instance or class variable:

class ApplicationController < ActionController::Base
  MY_CONSTANT_VALUE = "foo"
end

class MyViewController < ApplicationController
  def index
    raise MY_CONSTANT_VALUE.inspect
  end
end

You also could implement an helper:

# app/helpers/application_helper.rb
module ApplicationHelper
  FOO = "bar"
end

# app/controllers/foo_controller.rb
class FooController < ApplicationController
  def index
    raise FOO
  end
end