Polymorphic Association in rails - Controllers and Views?

Hi I'm trying to create an event depending on the eventable type. the eventable type is either group or shop.

Is there a special way to do this ?

here is what I have done so far:

Models:

class Event < ActiveRecord::Base
  belongs_to :eventable, polymorphic: true

class Group < ActiveRecord::Base
  has_many :events, as: :eventable

class Shop < ActiveRecord::Base
  has_many :events, as: :eventable

Routes:

resources :events do
  collection do
    get :new_national_event
    get :new_local_event
  end
do

event-controller:

def index
  @search   = Search.new(params[:search])
  @shop = find_user_shop(@search.shop_id)
  @group = @shop.group
  @shop_events = @shop.events
  @group_events = @group.events
end

def new_national_event
  @shop = find_user_shop(@search.shop_id)
  @group = @shop.group
  @event = @shop.events.new
end

def new_local_event
  @shop = find_user_shop(@search.shop_id)
  @event = @shop.events.new
end

view:

<%=link_to 'new national event' new_national_event_path%>
<%=link_to 'new local event' new_local_event_path%>

error:

undefined local variable or method `new_national_event_path' for #<#<Class:0x007f880ee00248>:0x007f880ee37f40>