* Denormalized post versions. Testing has shown it reduces the size

of the table 66%.

app/logical/date_tag.rb

@@ -34,7 +34,7 @@ class DateTag
   end
   
   def next_week
-    DateTag.new_from_range(1.week.since(start_date)), 1.week.since(end_date)
+    DateTag.new_from_range(1.week.since(start_date), 1.week.since(end_date))
   end
   
   def previous_month
@@ -42,7 +42,7 @@ class DateTag
   end
   
   def next_month
-    DateTag.new_from_range(1.month.since(start_date)), 1.month.since(end_date)
+    DateTag.new_from_range(1.month.since(start_date), 1.month.since(end_date))
   end
   
   def date

app/models/post.rb

@@ -1,7 +1,7 @@
 class Post < ActiveRecord::Base
   attr_accessor :old_tag_string, :old_parent_id
   after_destroy :delete_files
-  after_save :create_version  
+  after_save :update_history
   after_save :update_parent_on_save
   before_save :merge_old_tags
   before_save :normalize_tags
@@ -15,7 +15,7 @@ class Post < ActiveRecord::Base
   has_one :unapproval, :dependent => :destroy
   has_one :upload, :dependent => :destroy
   has_one :moderation_detail, :class_name => "PostModerationDetail", :dependent => :destroy
-  has_many :versions, :class_name => "PostVersion", :dependent => :destroy  
+  has_one :history, :class_name => "PostHistory"
   has_many :votes, :class_name => "PostVote", :dependent => :destroy
   has_many :notes, :dependent => :destroy
   has_many :comments
@@ -233,24 +233,21 @@ class Post < ActiveRecord::Base
     end
   end
   
-  module VersionMethods
+  module HistoryMethods
-    def create_version
+    def revisions
-      version = versions.create(
+      if history.nil?
-        :source => source,
+        update_history
-        :rating => rating,
+      end
-        :tag_string => tag_string,
+      
-        :updater_id => CurrentUser.user.id,
+      history.revisions
-        :updater_ip_addr => CurrentUser.ip_addr
-      )
-    
-      raise PostVersion::Error.new(version.errors.full_messages.join("; ")) if version.errors.any?
     end
     
-    def revert_to!(version)
+    def update_history
-      self.source = version.source
+      if history.nil?
-      self.rating = version.rating
+        create_history
-      self.tag_string = version.tag_string
+      end
-      save!
+
+      history << self
     end
   end
   
@@ -788,7 +785,7 @@ class Post < ActiveRecord::Base
   include ImageMethods
   include ApprovalMethods
   include PresenterMethods
-  include VersionMethods
+  include HistoryMethods
   include TagMethods
   include FavoriteMethods
   include UploaderMethods

app/models/post_history.rb

@@ -0,0 +1,40 @@
+class PostHistory < ActiveRecord::Base
+  class Error < Exception ; end
+
+  before_validation :initialize_revisions, :on => :create
+  belongs_to :post
+  
+  def self.build_revision_for_post(post)
+    hash = {
+      :source => post.source,
+      :rating => post.rating,
+      :tag_string => post.tag_string,
+      :parent_id => post.parent_id,
+      :user_id => CurrentUser.id,
+      :ip_addr => CurrentUser.ip_addr,
+      :updated_at => revision_time
+    }
+  end
+  
+  def self.revision_time
+    Time.now
+  end
+  
+  def initialize_revisions
+    write_attribute(:revisions, "[]")
+  end
+  
+  def revisions
+    if read_attribute(:revisions).blank?
+      []
+    else
+      JSON.parse(read_attribute(:revisions))
+    end
+  end
+  
+  def <<(post)
+    revision = self.class.build_revision_for_post(post)
+    write_attribute(:revisions, (revisions << revision).to_json)
+    save
+  end
+end

app/models/post_version.rb

@@ -1,6 +0,0 @@
-class PostVersion < ActiveRecord::Base
-  class Error < Exception ; end
-  
-  validates_presence_of :updater_id, :updater_ip_addr
-  belongs_to :post
-end

app/views/artists/_search.html.erb

@@ -1,5 +1,5 @@
 <div id="search-form" style="margin-bottom: 1em;">
-  <% form_tag(artists_path, :method => :get) do %>
+  <%= form_tag(artists_path, :method => :get) do %>
     <%= text_field_tag "name", params[:name], :size => 40 %>
     <%= submit_tag "Search" %>
   <% end %>

db/development_structure.sql

@@ -1013,6 +1013,38 @@ CREATE SEQUENCE pools_id_seq
 ALTER SEQUENCE pools_id_seq OWNED BY pools.id;
 
 
+--
+-- Name: post_histories; Type: TABLE; Schema: public; Owner: -; Tablespace: 
+--
+
+CREATE TABLE post_histories (
+    id integer NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
+    post_id integer NOT NULL,
+    revisions text NOT NULL
+);
+
+
+--
+-- Name: post_histories_id_seq; Type: SEQUENCE; Schema: public; Owner: -
+--
+
+CREATE SEQUENCE post_histories_id_seq
+    START WITH 1
+    INCREMENT BY 1
+    NO MAXVALUE
+    NO MINVALUE
+    CACHE 1;
+
+
+--
+-- Name: post_histories_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
+--
+
+ALTER SEQUENCE post_histories_id_seq OWNED BY post_histories.id;
+
+
 --
 -- Name: post_moderation_details; Type: TABLE; Schema: public; Owner: -; Tablespace: 
 --
@@ -1045,42 +1077,6 @@ CREATE SEQUENCE post_moderation_details_id_seq
 ALTER SEQUENCE post_moderation_details_id_seq OWNED BY post_moderation_details.id;
 
 
---
--- Name: post_versions; Type: TABLE; Schema: public; Owner: -; Tablespace: 
---
-
-CREATE TABLE post_versions (
-    id integer NOT NULL,
-    created_at timestamp without time zone,
-    updated_at timestamp without time zone,
-    post_id integer NOT NULL,
-    source character varying(255),
-    rating character(1) DEFAULT 'q'::bpchar NOT NULL,
-    tag_string text NOT NULL,
-    updater_id integer NOT NULL,
-    updater_ip_addr inet NOT NULL
-);
-
-
---
--- Name: post_versions_id_seq; Type: SEQUENCE; Schema: public; Owner: -
---
-
-CREATE SEQUENCE post_versions_id_seq
-    START WITH 1
-    INCREMENT BY 1
-    NO MAXVALUE
-    NO MINVALUE
-    CACHE 1;
-
-
---
--- Name: post_versions_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
---
-
-ALTER SEQUENCE post_versions_id_seq OWNED BY post_versions.id;
-
-
 --
 -- Name: post_votes; Type: TABLE; Schema: public; Owner: -; Tablespace: 
 --
@@ -1812,14 +1808,14 @@ ALTER TABLE pools ALTER COLUMN id SET DEFAULT nextval('pools_id_seq'::regclass);
 -- Name: id; Type: DEFAULT; Schema: public; Owner: -
 --
 
-ALTER TABLE post_moderation_details ALTER COLUMN id SET DEFAULT nextval('post_moderation_details_id_seq'::regclass);
+ALTER TABLE post_histories ALTER COLUMN id SET DEFAULT nextval('post_histories_id_seq'::regclass);
 
 
 --
 -- Name: id; Type: DEFAULT; Schema: public; Owner: -
 --
 
-ALTER TABLE post_versions ALTER COLUMN id SET DEFAULT nextval('post_versions_id_seq'::regclass);
+ALTER TABLE post_moderation_details ALTER COLUMN id SET DEFAULT nextval('post_moderation_details_id_seq'::regclass);
 
 
 --
@@ -2137,6 +2133,14 @@ ALTER TABLE ONLY pools
     ADD CONSTRAINT pools_pkey PRIMARY KEY (id);
 
 
+--
+-- Name: post_histories_pkey; Type: CONSTRAINT; Schema: public; Owner: -; Tablespace: 
+--
+
+ALTER TABLE ONLY post_histories
+    ADD CONSTRAINT post_histories_pkey PRIMARY KEY (id);
+
+
 --
 -- Name: post_moderation_details_pkey; Type: CONSTRAINT; Schema: public; Owner: -; Tablespace: 
 --
@@ -2145,14 +2149,6 @@ ALTER TABLE ONLY post_moderation_details
     ADD CONSTRAINT post_moderation_details_pkey PRIMARY KEY (id);
 
 
---
--- Name: post_versions_pkey; Type: CONSTRAINT; Schema: public; Owner: -; Tablespace: 
---
-
-ALTER TABLE ONLY post_versions
-    ADD CONSTRAINT post_versions_pkey PRIMARY KEY (id);
-
-
 --
 -- Name: post_votes_pkey; Type: CONSTRAINT; Schema: public; Owner: -; Tablespace: 
 --
@@ -2712,6 +2708,13 @@ CREATE INDEX index_pools_on_creator_id ON pools USING btree (creator_id);
 CREATE INDEX index_pools_on_name ON pools USING btree (name);
 
 
+--
+-- Name: index_post_histories_on_post_id; Type: INDEX; Schema: public; Owner: -; Tablespace: 
+--
+
+CREATE INDEX index_post_histories_on_post_id ON post_histories USING btree (post_id);
+
+
 --
 -- Name: index_post_moderation_details_on_post_id; Type: INDEX; Schema: public; Owner: -; Tablespace: 
 --
@@ -2726,20 +2729,6 @@ CREATE INDEX index_post_moderation_details_on_post_id ON post_moderation_details
 CREATE INDEX index_post_moderation_details_on_user_id ON post_moderation_details USING btree (user_id);
 
 
---
--- Name: index_post_versions_on_post_id; Type: INDEX; Schema: public; Owner: -; Tablespace: 
---
-
-CREATE INDEX index_post_versions_on_post_id ON post_versions USING btree (post_id);
-
-
---
--- Name: index_post_versions_on_updater_id; Type: INDEX; Schema: public; Owner: -; Tablespace: 
---
-
-CREATE INDEX index_post_versions_on_updater_id ON post_versions USING btree (updater_id);
-
-
 --
 -- Name: index_posts_on_created_at; Type: INDEX; Schema: public; Owner: -; Tablespace: 
 --

db/migrate/20100205163027_create_post_histories.rb

@@ -0,0 +1,16 @@
+class CreatePostHistories < ActiveRecord::Migration
+  def self.up
+    create_table :post_histories do |t|
+      t.timestamps
+      
+      t.column :post_id, :integer, :null => false
+      t.column :revisions, :text, :null => false
+    end
+    
+    add_index :post_histories, :post_id
+  end
+
+  def self.down
+    drop_table :post_histories
+  end
+end

db/migrate/20100205163027_create_post_versions.rb

@@ -1,26 +0,0 @@
-class CreatePostVersions < ActiveRecord::Migration
-  def self.up
-    create_table :post_versions do |t|
-      t.timestamps
-      
-      # Post
-      t.column :post_id, :integer, :null => false
-      
-      # Versioned
-      t.column :source, :string
-      t.column :rating, :character, :null => false, :default => 'q'
-      t.column :tag_string, :text, :null => false
-
-      # Updater
-      t.column :updater_id, :integer, :null => false
-      t.column :updater_ip_addr, "inet", :null => false
-    end
-    
-    add_index :post_versions, :post_id
-    add_index :post_versions, :updater_id
-  end
-
-  def self.down
-    drop_table :post_versions
-  end
-end

test/unit/post_history_test.rb

@@ -0,0 +1,33 @@
+require_relative '../test_helper'
+
+class PostHistoryTest < ActiveSupport::TestCase
+  context "A post" do
+    setup do
+      @user = Factory.create(:user)
+      CurrentUser.user = @user
+      CurrentUser.ip_addr = "127.0.0.1"
+      MEMCACHE.flush_all
+    end
+    
+    teardown do
+      CurrentUser.user = nil
+      CurrentUser.ip_addr = nil
+    end
+
+    should "create a revision after creation" do
+      PostHistory.stubs(:revision_time).returns("TIME")
+      post = Factory.create(:post, :tag_string => "aaa bbb ccc")
+      assert_equal(1, post.revisions.size)
+      assert_equal({"source"=>nil, "rating"=>"q", "tag_string"=>"aaa bbb ccc", "parent_id"=>nil, "user_id"=>1, "ip_addr"=>"127.0.0.1", "updated_at"=>"TIME"}, post.revisions.last)
+    end
+
+    should "create additional revisions after updating" do
+      PostHistory.stubs(:revision_time).returns("TIME")
+      post = Factory.create(:post, :tag_string => "aaa bbb ccc")
+      post.update_attributes(:tag_string => "bbb ccc ddd")
+      post.reload
+      assert_equal(2, post.revisions.size)
+      assert_equal({"source"=>nil, "rating"=>"q", "tag_string"=>"bbb ccc ddd", "parent_id"=>nil, "user_id"=>3, "ip_addr"=>"127.0.0.1", "updated_at"=>"TIME"}, post.revisions.last)
+    end
+  end
+end