Scoping controllers in rails routes

6_routes.rb

as :user do
    # Sessions
    get '/login' => 'users/sessions#new', as: :new_user_session
    
    # Registration
    controller 'users/registrations' do
      get '/signup', action: :new, as: :new_user_registration
    end
end

# can also do sth like this:
match '/auth/:provider/callback', to: 'sessions#create', via: [:get, :post]

## the ways we write in #sessions and #registrations are inter-changeable.