Dynamic namespaced controllers w/ fallback in Rails

Question

I have a somewhat bizarre requirement for a new Rails application. I need to build an application in which all routes are defined in multiple namespaces (let me explain). I want to have an application in which school subjects (math, english, etc) are the namespaces:

%w[math english].each do |subject|
  namespace subject.to_sym do
    resources :students
  end
end

This is great and it works but it requires me to create a namespaced StudentsController for each subject which means if I add a new subject then I need to create a new controller.

What I would like is to create a Base::StudentsController and if, let's say the Math::StudentsController exists then it will be used and if it doesn't exist, then we can dynamically create this controller and inherit from Base::StudentsController.

Is this something that is possible? If so then how would I go about implementing this?

Answer 1

With routes defined this way:

%w[math english].each do |subject|
  scope "/#{subject}" do
    begin
      "#{subject.camelcase}::StudentsController".constantize
      resources :students, controller: "#{subject}::students", only: :index
    rescue
      resources :students, controller: "base::students", only: :index
    end
  end
end

rake routes outputs:

students GET /math/students(.:format)    base::students#index
         GET /english/students(.:format) english::students#index

if english/students_controller.rb is present and math/students_controller. is absent.