add descendants_count to solve index sort by hot

app/controllers/messages_controller.rb

@@ -17,17 +17,25 @@ class MessagesController < ApplicationController
     @page  = params[:page]  || 1
     @page_size = params[:page_size] || 15
 
-    sort = params[:sort] || 0
+    sort = params[:sort].to_i == 1 ? 'asc' : 'desc'
     sort_type = params[:sort_type] || 'time'
-    sort = sort.to_i
-    sort_type = sort_type.strip
 
-    @messages = @board.messages.root_nodes.by_keywords(params[:search]).includes(:praise_treads, :author, :children)
-    @messages = @messages.ordered(sort: sort, sort_type: sort_type)
-    @messages = sort_by_all_replies(sort, sort_type, @messages)
+    messages = @board.messages.root_nodes.by_keywords(params[:search])
 
-    @messages = sort_by_sticky(@messages)
-    @messages = Kaminari.paginate_array(@messages).page(@page).per(@page_size)
+    messages = messages.order('(sticky = 1) DESC') # 置顶
+
+    messages =
+      case sort_type
+      when 'time' then messages.reorder("created_on #{sort}")
+      when 'hot' then messages.reorder("descendants_count #{sort}")
+      else messages.reorder("created_on #{sort}")
+      end
+
+    messages = messages.includes(:author)
+    @messages = Kaminari.paginate_array(messages).page(@page).per(@page_size)
+
+    ids = @messages.map(&:id)
+    @praises_count_map = Message.where(root_id: ids).group(:root_id).sum(:praises_count)
   end
 
   def reply_list
@@ -43,33 +51,16 @@ class MessagesController < ApplicationController
 
   def reply
     return normal_status(2, "回复内容不能为空") if params[:content].blank?
-    begin
-      @reply = Message.create!(board: @message.board,
-                              author: current_user,
-                              parent: @message,
-                              message_detail_attributes: {
+    @reply = Message.create!(board: @message.board, root: @message.root, author: current_user, parent: @message,
+                             message_detail_attributes: {
                                 content: params[:content]
-                              }
-                            )
-    rescue Exception => e
-      uid_logger_error(e.message)
-      tip_exception(e.message)
-      raise ActiveRecord::Rollback
-    end
+                             })
   end
 
   def sticky_top
     return normal_status(403, "您没有权限进行该操作") unless current_user.teacher_of_course?(@message.board.course)
 
-    ActiveRecord::Base.transaction do
-      begin
-        @message.update_attributes(:sticky => @message.sticky == 1 ? 0 : 1)
-      rescue Exception => e
-        uid_logger_error(e.message)
-        tip_exception(e.message)
-        raise ActiveRecord::Rollback
-      end
-    end
+    @message.update_attributes(:sticky => @message.sticky == 1 ? 0 : 1)
   end
 
   def bulk_delete

app/models/message.rb

@@ -4,6 +4,8 @@ class Message < ApplicationRecord
   belongs_to :board, counter_cache: true
   belongs_to :author, class_name: "User", foreign_key: 'author_id'
   belongs_to :parent, class_name: "Message", foreign_key: "parent_id", counter_cache: :replies_count, optional: true
+  belongs_to :root, class_name: 'Message', foreign_key: :root_id, counter_cache: :descendants_count, optional: true
+
   has_one :message_detail, dependent: :destroy
   accepts_nested_attributes_for :message_detail, update_only: true
 
@@ -12,6 +14,7 @@ class Message < ApplicationRecord
   has_many :tidings, as: :container, dependent: :destroy
   has_many :attachments, as: :container, dependent: :destroy
   has_many :course_acts, :class_name => 'CourseActivity',:as =>:course_act ,:dependent => :destroy # 课程动态
+  has_many :descendants, class_name: 'Message', foreign_key: :root_id, dependent: :destroy
 
   scope :root_nodes,       -> { where("parent_id IS NULL") }   #判断该信息是帖子还是回复。null为发布的帖子
   scope :reply_nodes,      -> { where("parent_id IS NOT NULL") }
@@ -70,24 +73,16 @@ class Message < ApplicationRecord
 
   # 包含二级回复的总点赞数
   def total_praises_count
-    praises_count + children.includes(:children).reduce(0) { |count, filed|
-      sub_sum_count = filed.children.reduce(0) { |sub_count, sub_filed| sub_count += sub_filed.praises_count }
-      count += filed.praises_count
-      sub_sum_count += count
-    }
+    descendants.sum(:praises_count)
   end
 
   # 包含二级回复数的总回复数
   def total_replies_count
-    replies_count + children.includes(:children).reduce(0) { |count, child|
-      sub_sum_count = child.children.reduce(0) { |sub_count, sub_child| sub_count += sub_child.replies_count }
-      count += child.replies_count
-      sub_sum_count += count
-    }
+    descendants_count
   end
 
   def has_replies
-    children.present?
+    children.exists?
   end
 
   #

app/views/messages/index.json.jbuilder

@@ -6,6 +6,11 @@ json.data do
   json.total_count @messages.total_count
   json.messages do
     json.array! @messages do |message|
+      json.extract! message, :id, :parent_id, :subject, :created_on, :total_replies_count,
+                    :praises_count, :visits, :sticky, :is_hidden, :is_public
+
+      json.total_praises_count @praises_count_map.fetch(message.id, 0)
+
       json.partial! "messages/message", message: message
       json.author do
         json.partial! "users/user_simple", user: message.author

db/migrate/20190621083604_add_descendants_count_to_messages.rb

@@ -0,0 +1,5 @@
+class AddDescendantsCountToMessages < ActiveRecord::Migration[5.2]
+  def change
+    add_column :messages, :descendants_count, :integer, default: 0
+  end
+end

lib/tasks/course_board_message_count.rake

@@ -20,6 +20,23 @@ namespace :course_board do
     end
   end
 
+  desc 'transfer root id && statistic descendants count'
+  task messages_descendants_count_transfer: :environment do
+    Message.root_nodes.find_each do |root|
+      logger("Current transfer root id: #{root.id} ~")
+      children_ids = root.children.pluck(:id)
+      next if children_ids.blank?
+
+      second_children_ids = Message.where(parent_id: children_ids).pluck(:id)
+
+      ids = children_ids.concat(second_children_ids).uniq
+      Message.where(id: ids).update_all(root_id: root.id)
+
+      Message.reset_counters(root.id, :descendants)
+      logger("transfer success ~")
+    end
+  end
+
   def logger(msg)
     puts msg
   end