Question

How do i cache a routes in to a variable, with lambda, but how to create it outside of the routes block?

somefile.rb that is loaded before the routes.rb block gets called:

x = lambda do
  namespace :test do

    root to: 'application#index'

    get 'page/:page', to: 'pages#show', as: :page

  end
end

routes.rb:

Rails.application.routes.draw do

  x.call if yep

end

Code like this doesn’t work because of some DSL class loading error. I don’t really understand how the scope works inside of blocks.

Answer 1

You can simply pass your lambda to the draw method directly:

# config/routes.rb
conditional_routes = lambda {
  namespace :test do
    root to: 'application#index'
    match 'page/:page' => 'pages#show', as: :page
  end
}

TestApp::Application.routes.draw do
  # default routes
end

TestApp::Application.routes.draw(&conditional_routes) if yep

In this example, I’m defining the lambda in the same file (config/routes.rb), but you could put it in an initializer or a library file or wherever you like:

# config/initializers/conditional_routes.rb
module ConditionalRoutes
  def self.routes
    lambda {
      # ...
    }
  end
end

# config/routes.rb
TestApp::Application.routes.draw(&ConditionalRoutes.routes)