#3

backend/app/controllers/posts_controller.rb

@@ -1,5 +1,14 @@
 class PostsController < ApplicationController
-  before_action :set_post, only: [:good, :bad, :destroy]
+  before_action :set_post, only: [:show, :good, :bad, :destroy]
+
+  def show
+    render json: @post.as_json.merge(image_url: (
+        if @post.image.attached?
+          Rails.application.routes.url_helpers.rails_blob_url(@post.image, only_path: true)
+        else
+          nil
+        end))
+  end
 
   # POST /posts/:id/good
   def good

backend/app/controllers/thread_posts_controller.rb

@@ -10,7 +10,14 @@ class ThreadPostsController < ApplicationController
             .select('posts.*, (good - bad) AS score')
             .order("#{ sort } #{ order }")
 
-    render json: posts
+    render json: posts.map { |post|
+      post.as_json.merge(image_url: (
+          if post.image.attached?
+            Rails.application.routes.url_helpers.rails_blob_url(post.image, only_path: true)
+          else
+            nil
+          end))
+    }
   end
 
   # POST /api/threads/:thread_id/posts

backend/app/controllers/threads_controller.rb

@@ -1,8 +1,10 @@
 class ThreadsController < ApplicationController
   # GET /api/threads
   def index
-    threads = Topic.order(updated_at: :desc)
-    render json: threads
+    threads = Topic.includes(:posts).order(updated_at: :desc)
+    render json: threads.map { |t|
+      t.as_json(methods: [:post_count])
+    }
   end
 
   # GET /api/threads/:id
@@ -15,7 +17,7 @@ class ThreadsController < ApplicationController
   def create
     thread = Topic.new(thread_params)
     if thread.save
-      render json: thread, status: :created
+      render json: thread.as_json, status: :created
     else
       render json: { errors: thread.errors.full_messages }, status: :unprocessable_entity
     end
@@ -24,6 +26,6 @@ class ThreadsController < ApplicationController
   private
 
   def thread_params
-    params.require(:thread).permit(:title, :description)
+    params.require(:thread).permit(:name, :description)
   end
 end