Default format

get 'photos/:id', to: 'photos#show', defaults: { format: 'jpg' }

defaults format: :json do
  resources :photos
end

Routes files

Create a new directory config/routes Add a routes file into this directory, for example admin.rb

# config/routes/admin.rb
namespace :admin
  roots 'users#index'
end

In the main routes file (config/routes.rb) we could import the routes file above like follow:

# config/routes.rb
draw :admin

Listing routes

# List all routes
rails routes
rails routes --expanded # display in expanded table format

# Find routes by grep
rails routes -g new_comment
# is equivalent to
rails routes | grep new_comment

# Find routes by controller
rails routes -c users
rails routes -c admin/users
rails routes -c Comments
rails routes -c Articles::CommentsController

References

• Rails Routing from the Outside In