修改开源项目社区中 每个项目的结构， 不再是一对一的匹配帖子，而是添加了一个中间表

app/models/open_source_project.rb

@@ -3,8 +3,10 @@ class OpenSourceProject < ActiveRecord::Base
 
   include Redmine::SafeAttributes
   has_many :applies, :class_name => "ApplyProjectMaster", :as => :apply, :dependent => :delete_all
-  has_many :topics, :class_name => 'RelativeMemo', :foreign_key => 'osp_id', :conditions => "#{RelativeMemo.table_name}.parent_id IS NULL", :order => "#{RelativeMemo.table_name}.created_at DESC", :dependent => :destroy
-  has_many :relative_memos, :class_name => 'RelativeMemo', :foreign_key => 'osp_id', :dependent => :destroy
+  has_many :relation_topics, :class_name => 'RelativeMemoToOpenSourceProject', :foreign_key => 'osp_id', :order => "#{RelativeMemo.table_name}.created_at DESC", :dependent => :destroy
+  # has_many :topics, :class_name => 'RelativeMemo', :foreign_key => 'osp_id', :conditions => "#{RelativeMemo.table_name}.parent_id IS NULL", :order => "#{RelativeMemo.table_name}.created_at DESC", :dependent => :destroy
+  has_many :topics, :through => :relation_topics, :class_name => 'RelativeMemo'
+  # has_many :relative_memos, :class_name => 'RelativeMemo', :foreign_key => 'osp_id', :dependent => :destroy
   has_many :tags, :through => :project_tags, :class_name => 'Tag'
   has_many :project_tags, :class_name => 'ProjectTags'
   has_many :masters, :class_name => 'ApplyProjectMaster', :as => :apply, :dependent => :delete_all, :conditions => "#{ApplyProjectMaster.table_name}.status = 2"
@@ -126,9 +128,14 @@ class OpenSourceProject < ActiveRecord::Base
 
   def self.reset_counters!(id)
     osp_id = id.to_i
-    update_all("topic_count = (SELECT COUNT(*) FROM #{RelativeMemo.table_name} WHERE osp_id=#{osp_id} AND parent_id IS NULL)," +
-     " memo_count = (SELECT COUNT(*) FROM #{RelativeMemo.table_name} WHERE osp_id=#{osp_id} AND parent_id IS NOT NULL)," +
-     " last_memo_id = (SELECT MAX(id) FROM #{RelativeMemo.table_name} WHERE osp_id=#{osp_id})",
+    # update_all("topic_count = (SELECT COUNT(*) FROM #{RelativeMemo.table_name} WHERE osp_id=#{osp_id} AND parent_id IS NULL)," +
+     # " memo_count = (SELECT COUNT(*) FROM #{RelativeMemo.table_name} WHERE osp_id=#{osp_id} AND parent_id IS NOT NULL)," +
+     # " last_memo_id = (SELECT MAX(id) FROM #{RelativeMemo.table_name} WHERE osp_id=#{osp_id})",
+     # ["id = ?", osp_id])
+     update_all("topic_count = (SELECT COUNT(*) FROM #{RelativeMemoToOpenSourceProject.table_name} WHERE osp_id=#{osp_id})", 
+     # +
+     # " memo_count = (SELECT COUNT(*) FROM #{RelativeMemo.table_name} WHERE osp_id=#{osp_id} AND parent_id IS NOT NULL)," +
+     # " last_memo_id = (SELECT MAX(id) FROM #{RelativeMemo.table_name} WHERE osp_id=#{osp_id})",
      ["id = ?", osp_id])
   end
 end

app/models/relative_memo.rb

@@ -7,6 +7,8 @@ class RelativeMemo < ActiveRecord::Base
   has_many :tags, :through => :project_tags, :class_name => 'Tag'
   has_many :project_tags, :class_name => 'ProjectTags'
   
+  has_many :relation_topics, :class_name => 'RelativeMemoToOpenSourceProject'
+  
   has_many :no_uses, :as => :no_use, :dependent => :delete_all
   
   acts_as_taggable 

app/models/relative_memo_to_open_source_project.rb

@@ -1,3 +1,7 @@
 class RelativeMemoToOpenSourceProject < ActiveRecord::Base
   # attr_accessible :title, :body
+  belongs_to :open_source_project, :foreign_key => "osp_id"
+  belongs_to :relative_memo, :foreign_key => 'relative_memo_id'
+  
+  validates_presence_of :osp_id, :relative_memo_id
 end

db/migrate/20140401004102_create_relative_memos.rb

@@ -1,10 +1,10 @@
 class CreateRelativeMemos < ActiveRecord::Migration
   def change
     create_table :relative_memos do |t|
-      t.integer :osp_id, :null => false
+      t.integer :osp_id, :null => true
       t.integer :parent_id, null: true
       t.string :subject, null: false
-      t.text :content, null: false
+      t.mediumtext :content, null: false
       t.integer :author_id
       t.integer :replies_count, default: 0
       t.integer :last_reply_id