Rails routes cached in a variable - ruby-on-rails-3

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)

Answer 2

In your initializer:
class Routes
attr_accessor :routes
def initialize(routes)
#routes = routes
end
module Helper
def test_namespace
Routes.new(self).create_routes
end
end
def self.install!
ActionDispatch::Routing::Mapper.send :include, Routes::Helper
end
def create_routes
routes.namespace :test do
root to: 'application#index'
get 'page/:page', to: 'pages#show', as: :page
end
end
end
Routes.install!
In your routes
Rails.application.routes.draw do
test_namespace if yep
end
I'm REALLY not sure it will work, but it might give you ideas.

Answer 3

It's usually a good practice to keep the route declarations explicit within routes.rb. The routes.rb file is intended to be the only place you have to look to see how routes are defined.
Also, no need to make a call to routes.draw twice.
routes.rb
TestApp::Application.routes.draw do
constraints(Yep) do
namespace :test do
root to: 'application#index'
get 'page/:page', to: 'pages#show', as: :page
end
end
end
lib/yep.rb
class Yep
def self.matches?(request)
# if this returns true, your routes block will be drawn
end
end