Rails上嵌套资源和简单资源红宝石中的多态注释4

Question

I have following relationship routes:

resources :courses, only: [:index, :show] do
  resources :enrols, only: [:new, :create]
  resources :lectures, only: [:show]
end

resources :code_casts, :path => 'casts', :as => 'casts', only: [:index, :show]
resources :blogs, :path => 'blog', :as => 'blog', only: [:index, :show] do
  resources :blog_votes, only: [:create, :destroy]
end

I want polymorphic comments in courses, lectures, code_casts and blog.

Problem is lecture has a parent of course so route will be course/course_id/lecture/id and blog path will blog/id where comments will have different show pages.

Answer 1

If I understand the problem correctly, there is nothing special about deeply nested resources. So you might need something like this

# routes.rb
concern :commentable do
  resources :comments
end

resources :courses, only: [:index, :show] do
  resources :enrols, only: [:new, :create]
  resources :lectures, only: [:show], concerns: [:commentable]
end

resources :code_casts, :path => 'casts', :as => 'casts', only: [:index, :show]
resources :blogs, :path => 'blog', :as => 'blog', only: [:index, :show], concerns: [:commentable] do
  resources :blog_votes, only: [:create, :destroy]
end

This will create nested comments resources for lectures and blogs. Than you need to differentiate the path in a comments controller

# comments_controller
def create
  Comment.create(commentable: commentable, other_params...) # assuming you have `commentable` polymorphic belongs_to
end

# a little more ugly than Ryan suggests
def commentable
  if request.path.include?('blog') # be careful. any path with 'blog' in it will match
    Blog.find(params[:id]) 
  elsif params[:course_id] && request.path.include?('lecture')
    Course.find(params[:course_id).leactures.find(params[:id]) # assuming Course has_many lectures
  else
    fail 'unnable to determine commentable type'
  end
end

All 'magic' is in commentable method, where youare checking the path and determine which commentable object to pick. I use similar approach, but this exact code is written by memory without testing. Hopefully you've got the idea.