get rid of nonsense 404.html

correct 404 handling for invalid pages

app/controllers/application_controller.rb

@@ -65,14 +65,13 @@ class ApplicationController < ActionController::Base
   end
 
   rescue_from Discourse::NotFound do
-    if !request.format || request.format.html?
-      # for now do a simple remap, we may look at cleaner ways of doing the render
-      #
-      # Sam: I am confused about this, we need a comment that explains why this is conditional
-      raise ActiveRecord::RecordNotFound
-    else
-      render file: 'public/404', formats: [:html], layout: false, status: 404
-    end
+
+    f = Topic.where(deleted_at: nil, archetype: "regular")
+    @latest = f.order('views desc').take(10)
+    @recent = f.order('created_at desc').take(10)
+    @slug =  params[:slug].class == String ? params[:slug] : ''
+    @slug.gsub!('-',' ')
+    render status: 404, layout: 'no_js', template: '/exceptions/not_found'
   end
 
   rescue_from Discourse::InvalidAccess do

app/controllers/exceptions_controller.rb

@@ -1,14 +1,9 @@
 class ExceptionsController < ApplicationController
   skip_before_filter :check_xhr
-  layout 'no_js'
 
   def not_found
-    f = Topic.where(deleted_at: nil, archetype: "regular")
-
-    @latest = f.order('views desc').take(10)
-    @recent = f.order('created_at desc').take(10)
-    @slug =  params[:slug].class == String ? params[:slug] : ''
-    @slug.gsub!('-',' ')
-    render status: 404
+    # centralize all rendering of 404 into app controller
+    raise Discourse::NotFound
   end
+
 end

app/controllers/static_controller.rb

@@ -21,7 +21,7 @@ class StaticController < ApplicationController
       return
     end
 
-    render file: 'public/404', layout: false, status: 404
+    raise Discourse::NotFound
   end
 
   # This method just redirects to a given url.

app/controllers/topics_controller.rb

@@ -25,7 +25,10 @@ class TopicsController < ApplicationController
   caches_action :avatar, cache_path: Proc.new {|c| "#{c.params[:post_number]}-#{c.params[:topic_id]}" }
 
   def show
-    create_topic_view
+    opts = params.slice(:username_filters, :best_of, :page, :post_number, :posts_before, :posts_after, :best)
+    @topic_view = TopicView.new(params[:id] || params[:topic_id], current_user, opts)
+
+    raise Discourse::NotFound unless @topic_view.posts.present?
 
     anonymous_etag(@topic_view.topic) do
       redirect_to_correct_topic && return if slugs_do_not_match
@@ -196,11 +199,6 @@ class TopicsController < ApplicationController
 
   private
 
-  def create_topic_view
-    opts = params.slice(:username_filters, :best_of, :page, :post_number, :posts_before, :posts_after, :best)
-    @topic_view = TopicView.new(params[:id] || params[:topic_id], current_user, opts)
-  end
-
   def toggle_mute(v)
     @topic = Topic.where(id: params[:topic_id].to_i).first
     guardian.ensure_can_see!(@topic)