FEATURE: automatically rebake out-of-date posts

app/jobs/scheduled/periodical_updates.rb

@@ -26,6 +26,9 @@ module Jobs
 
       # Automatically close stuff that we missed
       Topic.auto_close
+
+      # Forces rebake of old posts where needed
+      Post.rebake_old(250)
     end
 
   end

app/models/post.rb

@@ -15,6 +15,10 @@ class Post < ActiveRecord::Base
   include Trashable
   include HasCustomFields
 
+  # rebake all posts baked before this date
+  # in our periodical job
+  REBAKE_BEFORE = Time.new(2014,5,27)
+
   rate_limit
   rate_limit :limit_posts_per_day
 
@@ -310,6 +314,35 @@ class Post < ActiveRecord::Base
     PostRevisor.new(self).revise!(updated_by, new_raw, opts)
   end
 
+  def self.rebake_old(limit)
+    Post.where('baked_at IS NULL OR baked_at < ?', REBAKE_BEFORE)
+        .limit(limit).each do |p|
+      begin
+        p.rebake!
+      rescue => e
+        Discourse.handle_exception(e)
+      end
+    end
+  end
+
+  def rebake!(opts={})
+    new_cooked = cook(
+      raw,
+      topic_id: topic_id,
+      invalidate_oneboxes: opts.fetch(:invalidate_oneboxes, false)
+    )
+    old_cooked = cooked
+
+    update_columns(cooked: new_cooked, baked_at: Time.new)
+
+    # Extracts urls from the body
+    TopicLink.extract_from self
+    # make sure we trigger the post process
+    trigger_post_process(true)
+
+    new_cooked != old_cooked
+  end
+
   def set_owner(new_user, actor)
     revise(actor, self.raw, {
         new_user: new_user,
@@ -357,6 +390,7 @@ class Post < ActiveRecord::Base
   before_save do
     self.last_editor_id ||= user_id
     self.cooked = cook(raw, topic_id: topic_id) unless new_record?
+    self.baked_at = Time.new
   end
 
   after_save do

db/migrate/20140528015354_add_baked_at_to_posts.rb

@@ -0,0 +1,5 @@
+class AddBakedAtToPosts < ActiveRecord::Migration
+  def change
+    add_column :posts, :baked_at, :datetime
+  end
+end

lib/tasks/posts.rake

@@ -9,25 +9,12 @@ task 'posts:refresh_oneboxes' => :environment do
 end
 
 def rebake_post(post,opts)
-  cooked = post.cook(
-    post.raw,
-    topic_id: post.topic_id,
-    invalidate_oneboxes: opts.fetch(:invalidate_oneboxes, false)
-  )
-
-  if cooked != post.cooked
-    Post.exec_sql('update posts set cooked = ? where id = ?', cooked, post.id)
-    post.cooked = cooked
+  changed = post.rebake!(opts)
+  if changed
     putc "#"
   else
     putc "."
   end
-
-  # Extracts urls from the body
-  TopicLink.extract_from post
-  # make sure we trigger the post process
-  post.trigger_post_process(true)
-
 rescue => e
   puts "\n\nFailed to bake topic_id #{post.topic_id} post_id #{post.id} #{e}\n#{e.backtrace.join("\n")} \n\n"
 end

spec/models/post_spec.rb

@@ -11,8 +11,6 @@ describe Post do
     Fabricate.build(:post, args)
   end
 
-  it { should belong_to :user }
-  it { should belong_to :topic }
   it { should validate_presence_of :raw }
 
   # Min/max body lengths, respecting padding
@@ -20,17 +18,6 @@ describe Post do
   it { should_not allow_value("x" * (SiteSetting.max_post_length + 1)).for(:raw) }
   it { should_not allow_value((" " * SiteSetting.min_post_length) + "x").for(:raw) }
 
-  it { should have_many :post_replies }
-  it { should have_many :replies }
-
-  it { should have_many :post_uploads }
-  it { should have_many :uploads }
-
-  it { should have_many :post_details }
-
-  it { should have_many :post_revisions }
-  it { should have_many :revisions}
-
   it { should rate_limit }
 
   let(:topic) { Fabricate(:topic) }
@@ -805,11 +792,11 @@ describe Post do
 
       post.has_host_spam?.should == false
 
-      SiteSetting.stubs(:newuser_spam_host_threshold).returns(1)
+      SiteSetting.newuser_spam_host_threshold = 1
 
       post.has_host_spam?.should == true
 
-      SiteSetting.stubs(:white_listed_spam_host_domains).returns("bla.com|boo.com | somesite.com ")
+      SiteSetting.white_listed_spam_host_domains = "bla.com|boo.com | somesite.com "
       post.has_host_spam?.should == false
     end
   end
@@ -826,4 +813,33 @@ describe Post do
     post.custom_fields.should == {"Tommy" => "Hanks", "Vincent" => "Vega"}
   end
 
+  describe "#rebake!" do
+    it "will rebake a post correctly" do
+      post = create_post
+      post.baked_at.should_not == nil
+      first_baked = post.baked_at
+      first_cooked = post.cooked
+
+      Post.exec_sql("UPDATE posts SET cooked = 'frogs' WHERE id = ?", post.id)
+      post.reload
+
+      result = post.rebake!
+
+      post.baked_at.should_not == first_baked
+      post.cooked.should == first_cooked
+      result.should == true
+    end
+  end
+
+  describe ".rebake_old" do
+    it "will catch posts it needs to rebake" do
+      post = create_post
+      post.update_column(:baked_at, Time.new(2000,1,1))
+      Post.rebake_old(100)
+
+      post.reload
+      post.baked_at.should > 1.day.ago
+    end
+  end
+
 end