Question

In my app I have a user model, school model, course model, and a syllabus model. A user or school could create courses which I have set through a polymorphic association (course belongs_to :hostable, and school/user has_many :courses, as: :hostable) , and a course has_one syllabus. My question is how to configure the routes for the nested course model which also has a syllabus model nested within it.

resources :users do
  resources :courses do
   resources :syllabus
  end 
    member do
    put :enroll
   end
  end

 resources :schools do
  resources :courses do 
   resources :syllabuses
  end
   member do
  put :apply, :enroll
  end
end

So users can enroll in courses by clicking a button on the course page, in my courses controller I have:

def enroll
  @course = Course.find(params[:id])
  current_user.coursegroups.create(host_course_id: @course.id, role: 'applicant')
  respond_with @course
end

So, is this the correct way to configure my routes?

Answer 1

Stefan’s right that you should be careful about nesting resources more than one level deep, but I personally don’t find nesting unmanageable until two levels. Either way, it’s just a personal preference.

For your routes, the one thing that immediately jumps out at me is that nesting everything inside users and schools isn’t necessary, since it sounds like you’ll be logging in as a user or school. Routes with the logged-in user in them are very difficult to manage: users can’t share them and they don’t really reflect the state of the specified resource. For example:

/users/1/courses/14/syllabus/3

Theoretically, courses/14/syllabus/3 should work the same for every logged-in user, but anyone trying to share a link to this would need to include their own user ID number first, which is somewhat silly. Instead structure your routes like so:

resource :sessions
resources :courses do
  resources :syllabus
  member do
    put :apply, :enroll
  end
end

In your session, allow either a user or school to log in, and vary what they see in the views (and what resources they’re allowed to access) based on who’s logged in using something like CanCan. Now your routes will reflect the actual resource (/courses/14/syllabus/3) correctly.