remove old activity feeds

app/models/activity_feed.rb

@@ -10,6 +10,7 @@ class ActivityFeed < ActiveRecord::Base
   serialize :data
 
   default_scope order('created_at DESC')
+  scope :outdated, offset(100)
 
   self.per_page = 10
 

config/schedule.rb

@@ -18,3 +18,7 @@ end
 every 1.day, :at => '3:30 am' do
   rake "pull_requests:clear", :output => 'log/pull_requests_clear.log'
 end
+
+every 1.day, :at => '3:00 am' do
+  rake "activity_feeds:clear", :output => 'log/activity_feeds.log'
+end

lib/tasks/activity_feeds.rake

@@ -0,0 +1,12 @@
+namespace :activity_feeds do
+  desc 'Remove outdated activity feeds'
+  task :clear => :environment do
+    say "Removing outdated Activity Feed"
+    User.all.each do |user|
+      outdated = ActivityFeed.outdated
+      say "User #{user.uname} has #{outdated.count} outdated ActivityFeed."
+      user.activity_feeds.outdated.destroy_all if outdated.count > 0
+    end
+    say "Outdated activity feeds was successfully removed."
+  end
+end