Rails 4 nested routes without all RESTful routes

Question

I have a SchedulesController which corresponds to a Schedule class which is not an ActiveRecord model. The only action in SchedulesController is show .

Then I have a Shift ActiveRecord model and a ShiftsController .

In the schedules/show view, there is a link the user can click to bring in a form for a new Shift . This form is retrieved from the ShiftsController via an ajax request. Because the request url will be packaged as schedules/shifts/new , I need the shifts routes to be nested within the schedules routes.

However, I'd like to avoid generating all the RESTful routes for schedules , just to keep things clean. I only need show . This takes care of that:

# config/routes.rb

get "schedules/show"
resources :schedules, only: [] do
  collection do
    resources :shifts
  end
end

Note that I use get "schedules/show" because I don't want show to be handled the usual way, where it requires an ID. I might change the show action to display to resolve that confusion. Anyway, here are the routes that this generates:

$ rake routes
Prefix         Verb   URI Pattern                          Controller#Action
schedules_show GET    /schedules/show(.:format)            schedules#show
shifts         GET    /schedules/shifts(.:format)          shifts#index
               POST   /schedules/shifts(.:format)          shifts#create
new_shift      GET    /schedules/shifts/new(.:format)      shifts#new
edit_shift     GET    /schedules/shifts/:id/edit(.:format) shifts#edit
shift          GET    /schedules/shifts/:id(.:format)      shifts#show
               PATCH  /schedules/shifts/:id(.:format)      shifts#update
               PUT    /schedules/shifts/:id(.:format)      shifts#update
               DELETE /schedules/shifts/:id(.:format)      shifts#destroy

This solution works; I can pull in the new_shift form on the schedules/show page. The problem is that it creates all the RESTful routes for schedules/shifts , and I only need one right now, new . So I tried this:

# config/routes.rb

get "schedule/show"
resources :schedules, only: [] do
  collection do
    resources :shifts, only: [:new]
  end
end

And that's where I run into a problem. Here are the routes:

$ rake routes
Prefix         Verb URI Pattern                     Controller#Action
schedules_show GET  /schedules/show(.:format)       schedules#show
new_shift      GET  /schedules/shifts/new(.:format) shifts#new

That looks okay to me (?). But when I go to the schedules/show page and click the link that's supposed to bring in the new_shift form, I get this exception:

Started GET "/schedules/shifts/new" for 127.0.0.1 at 2013-09-29 19:59:52 -0400
  ActiveRecord::SchemaMigration Load (0.9ms)  SELECT "schema_migrations".* FROM "schema_migrations"
Processing by ShiftsController#new as HTML
  Rendered shifts/new.html.erb within layouts/application (135.6ms)
Completed 500 Internal Server Error in 272ms

ActionView::Template::Error (undefined method `shifts_path' for #<#<Class:0x7578de90>:0x7578d4d0>):
    1: <%= form_for @shift do |f| %>
    2:   <%= f.text_field :start_time %>
    3:   <%= f.text_field :end_time %>
    4: <% end %>
  app/views/shifts/new.html.erb:1:in `_app_views_shifts_new_html_erb__535553616_985195992'
  app/controllers/shifts_controller.rb:8:in `new'

I assume #<#<Class:0x7578de90>:0x7578d4d0> refers to my Schedule class, which as I said above is not an ActiveRecord model. But why does it not work here, but does when I do it the other way? In both cases, the GET /schedules/shifts/new(.:format) route is exactly the same when I run rake routes .

Any ideas? Thanks!

Answer 1

By Rails conventions, your form is trying to do a POST request to a path named shifts_path , only it cannot find that path method because there isn't a route defined for the #create action.

You need a route for #create as well as #new .

resources :shifts, only: [:new, :create]