posts: fix search queries not being logged to NewRelic in some cases (#4900)

Fix the /posts index controller not logging the normalized search query
to NewRelic when the search failed, either because of a tag limit error,
a search timeout, or a RSS feed rate limit error.

Also don't log the number of search results when it's an API request or
failed search. This is to avoid doing a potentially slow full post count
when it's not otherwise needed.

app/controllers/posts_controller.rb

@@ -4,6 +4,8 @@ class PostsController < ApplicationController
   respond_to :html, :xml, :json, :js
   layout "sidebar"
 
+  before_action :log_search_query, only: :index
+  after_action :log_search_count, only: :index, if: -> { request.format.html? && response.successful? }
   rate_limit :index, rate: 1.0/2.seconds, burst: 50, if: -> { request.format.atom? }, key: "posts:index.atom"
 
   def index
@@ -13,16 +15,11 @@ class PostsController < ApplicationController
         format.html { redirect_to(@post) }
       end
     elsif params[:random].to_s.truthy?
-      post_set = PostSets::Post.new(params[:tags], params[:page], params[:limit], format: request.format.symbol)
       query = "#{post_set.normalized_query.to_s} random:#{post_set.per_page}".strip
       redirect_to posts_path(tags: query, page: params[:page], limit: params[:limit], format: request.format.symbol)
     else
-      tag_query = params[:tags] || params.dig(:post, :tags)
-      @show_votes = (params[:show_votes].presence || cookies[:post_preview_show_votes].presence || "false").truthy?
-      @post_set = PostSets::Post.new(tag_query, params[:page], params[:limit], format: request.format.symbol, show_votes: @show_votes)
       @preview_size = params[:size].presence || cookies[:post_preview_size].presence || PostGalleryComponent::DEFAULT_SIZE
-      @posts = authorize @post_set.posts, policy_class: PostPolicy
-      @post_set.log!
+      @posts = authorize post_set.posts, policy_class: PostPolicy
       respond_with(@posts) do |format|
         format.atom
       end
@@ -118,6 +115,29 @@ class PostsController < ApplicationController
 
   private
 
+  def post_set
+    @post_set ||= begin
+      tag_query = params[:tags] || params.dig(:post, :tags)
+      show_votes = (params[:show_votes].presence || cookies[:post_preview_show_votes].presence || "false").truthy?
+      PostSets::Post.new(tag_query, params[:page], params[:limit], format: request.format.symbol, show_votes: show_votes)
+    end
+  end
+
+  def log_search_query
+    DanbooruLogger.add_attributes("search", {
+      query: post_set.normalized_query.to_s,
+      page: post_set.current_page,
+      limit: post_set.per_page,
+      term_count: post_set.normalized_query.terms.count,
+      tag_count: post_set.normalized_query.tags.count,
+      metatag_count: post_set.normalized_query.metatags.count,
+    })
+  end
+
+  def log_search_count
+    DanbooruLogger.add_attributes("search", { count: post_set.post_count, })
+  end
+
   def respond_with_post_after_update(post)
     respond_with(post) do |format|
       format.html do

app/logical/post_query_builder.rb

@@ -968,7 +968,7 @@ class PostQueryBuilder
 
   concerning :CountMethods do
     def post_count
-      fast_count
+      @post_count ||= fast_count
     end
 
     # Return an estimate of the number of posts returned by the search.  By

app/logical/post_sets/post.rb

@@ -137,24 +137,6 @@ module PostSets
       end
     end
 
-    def search_stats
-      {
-        query: normalized_query.to_s,
-        count: post_count,
-        page: current_page,
-        limit: per_page,
-        term_count: normalized_query.terms.count,
-        tag_count: normalized_query.tags.count,
-        metatag_count: normalized_query.metatags.count,
-        censored_posts: censored_posts.count,
-        hidden_posts: hidden_posts.count,
-      }
-    end
-
-    def log!
-      DanbooruLogger.add_attributes("search", search_stats)
-    end
-
     concerning :TagListMethods do
       def related_tags
         if query.is_wildcard_search?

app/views/posts/index.html.erb

@@ -134,7 +134,7 @@
 
     <%= render PopupMenuComponent.new(classes: "post-preview-options-menu") do |menu| %>
       <% menu.item do %>
-        <% if @show_votes %>
+        <% if @post_set.show_votes %>
           <%= link_to "Hide scores", posts_path(tags: params[:tags], page: params[:page], limit: params[:limit], show_votes: nil, size: params[:size]), class: "post-preview-hide-votes", rel: "nofollow" %>
         <% else %>
           <%= link_to "Show scores", posts_path(tags: params[:tags], page: params[:page], limit: params[:limit], show_votes: true, size: params[:size]), class: "post-preview-show-votes", rel: "nofollow" %>

test/functional/posts_controller_test.rb

@@ -458,7 +458,7 @@ class PostsControllerTest < ActionDispatch::IntegrationTest
       context "for a search that times out" do
         context "during numbered pagination" do
           should "show the search timeout error page" do
-            Post::const_get(:ActiveRecord_Relation).any_instance.stubs(:records).raises(ActiveRecord::QueryCanceled)
+            PostSets::Post.any_instance.stubs(:posts).raises(ActiveRecord::QueryCanceled)
 
             get posts_path(page: "1")
             assert_response 500
@@ -468,7 +468,7 @@ class PostsControllerTest < ActionDispatch::IntegrationTest
 
         context "during sequential pagination" do
           should "show the search timeout error page" do
-            Post::const_get(:ActiveRecord_Relation).any_instance.stubs(:records).raises(ActiveRecord::QueryCanceled)
+            PostSets::Post.any_instance.stubs(:posts).raises(ActiveRecord::QueryCanceled)
 
             get posts_path(page: "a0")
             assert_response 500