How to move Rails Engine's route to rails main routes?

Question

I'm using Rails 4.2 with Rails Engine to handle my admin panel. I want to move the engine code to the main rails app and part of doing that is moving the routes.

For now, my routes in the Engine my-web-app/lib/admin/config/routes.rb is something like:

Admin::Engine.routes.draw do
  resources :countries, only: [:index]
end

And at my app's routes config/routes.rb :

Rails.application.routes.draw do
  .. some routes ...
  mount GlobalAdmin::Engine => "/admin"
end

Now the engine's route for countries is countries_url NOT admin_countries_url but for URL you'll need to access it with something like admin/countries (this is the default behavior for the engine and I want to keep it this way).

What I did is that I moved my-web-app/lib/admin/config/routes.rb to my-web-app//config/routes.admin.rb and made it look something like:

Rails.application.routes.draw do
  resources :countries, only: [:index]
end

And then in my config/application.rb I added something like this:

config.paths["config/routes.rb"] = [
  Rails.root.join("config/routes.admin.rb"),
  Rails.root.join("config/routes.rb")
]

The problem with this approach is that I have countries_url , however, I can't access it with admin namespace URL like admin/countries . If I add namespace admin something like:

Rails.application.routes.draw do
  namespace :admin do
    resources :countries, only: [:index]
  end
end

Then I'll need to refer to countries url with admin_countries_url which is not the behavior I need.

Any help of how to move the routes from the engine without affecting the previous engine routes?

I'm aware that routes inside an engine are isolated from the application by default. The application and its engines can have routes with the same names, so integrating both can cause some issues, however I want to preserve the exact routes if possible and not to add a namespace and stick with the exact routes names.

Answer 1

Use scope instead of namespace :

Rails.application.routes.draw do
  scope path: "/admin" do
    resources :countries
  end
end

---

max@MaxBook ~/p/sandbox> rails routes
      Prefix Verb   URI Pattern                         Controller#Action
   countries GET    /admin/countries(.:format)          countries#index
             POST   /admin/countries(.:format)          countries#create
 new_country GET    /admin/countries/new(.:format)      countries#new
edit_country GET    /admin/countries/:id/edit(.:format) countries#edit
     country GET    /admin/countries/:id(.:format)      countries#show
             PATCH  /admin/countries/:id(.:format)      countries#update
             PUT    /admin/countries/:id(.:format)      countries#update
             DELETE /admin/countries/:id(.:format)      countries#destroy