Rails routing using devise and subdomain constraint

Question

I am trying to route root to devise sign in path under a subdomain constraint.

My config/routes.rb look something like this

Rails.application.routes.draw 
  constraints subdomain: 'admin' do
    devise_scope :admin do
      root to: 'devise/sessions#new'

      # here I override devise routes
    end
  end

  root to: 'pages#homepage'

  # rest of the routes  
end

I am getting the error Could not find devise mapping for path "/".

Any suggestions as to how I route to root path in a subdomain with devise scope?

Thanks

Answer 1

To add an authentication constrain to a route use the devise authenticated method:

Rails.application.routes.draw 
  constraints subdomain: 'admin' do
    authenticated :admin do
      # the root page for authenticated users
      root 'admin#dashboard', as: :authenticated_root
    end
    root to: 'devise/sessions#new'
  end

  # this is for no subdomain
  root to: 'pages#homepage'
end