Users destroy

users.rake

# lib/tasks/users.rake
namespace :users do
  task spam_clean: :environment do
    failed_list = []
    no_users_without_enrollments = 0
    
    number_of_thread = (ENV['THREADS'] || 10).to_i
    total_users = User.count.to_f
    offset = (total_users / number_of_thread).ceil
    
    id = User.unscoped.order(id: :asc).first.id

    theads = []
    number_of_thread.times.each do |i|
      users = User.unscoped.order(id: :asc).where("id > ?", id).limit(offset)

      theads << Thread.new do
        puts "Start thread #{i+1}; #{users.count}"

        users.find_each do |user|
          if user.enrollments.empty?
            no_users_without_enrollments += 1
            
            begin
              delete_user user
            rescue Exception => ex  
              failed_list << user.id 
            end
          end
        end
      end
      
      id = users.last.id
    end

    theads.each do |thread|
      thread.join
    end

    p "Total users to delete: #{no_users_without_enrollments}"
    p "Total users that not deleted: #{failed_list.length}"

    debug_list(failed_list)
  end

  def debug_list failed_list
    #########################################
    # Debug failed reason from list of failed
    failed_list.each do |user_id|
      begin 
        user = User.find_by(id: user_id)
        user.delete
      rescue Exception => ex
        p "#{user_id}: => #{ex.message}"
      end
    end
  end

  def delete_user user
    user.destroy
    user.eportfolios.each do |port|
      port.eportfolio_entries.delete_all
      port.eportfolio_categories.delete_all
    end
    
    user.account_users.destroy_all
    user.account_users.unscope(where: :workflow_state).delete_all
    
    user.profile.destroy
    
    UserMergeData.where(user_id: user.id).each do |um|
      UserMergeDataRecord.where(user_merge_data_id: um.id).destroy_all
      UserMergeDataRecord.where(user_merge_data_id: um.id).delete_all
      um.destroy
    end

    UserMergeData.unscoped.where(user_id: user.id).delete_all

    UserMergeDataItem.where(user_id: user.id).destroy_all
    UserMergeDataItem.where(user_id: user.id).delete_all
    
    Submission.unscoped.where(user_id: user.id).destroy_all
    user.web_conference_participants.destroy_all
    WebConference.where(user_id: user.id).each do |w|
      w.web_conference_participants.destroy_all
      w.delete
    end
    
    user.user_preference_values.destroy_all
    user.access_tokens.delete_all

    WikiPage.where(user_id: user.id).destroy_all
    WikiPage.unscoped.where(user_id: user.id).delete_all

    PageComment.where(user_id: user.id).destroy_all
    PageComment.unscoped.where(user_id: user.id).delete_all

    DiscussionTopicParticipant.where(user_id: user.id).destroy_all
    DiscussionTopicParticipant.unscoped.where(user_id: user.id).delete_all

    Auditors::ActiveRecord::CourseRecord.where(user_id: user.id).destroy_all
    Auditors::ActiveRecord::CourseRecord.unscoped.where(user_id: user.id).delete_all

    DiscussionTopic.unscoped.where(user_id: user.id).each do |dt|
      ActiveRecord::Base.connection.execute("delete from discussion_topic_materialized_views where discussion_topic_id = #{dt.id}")
      ActiveRecord::Base.connection.execute("delete from discussion_topic_participants where discussion_topic_id = #{dt.id}")
      dt.discussion_entries.each do |de|
        DiscussionEntryParticipant.unscoped.where(discussion_entry_id: de.id).destroy_all
        DiscussionEntryParticipant.unscoped.where(discussion_entry_id: de.id).delete_all
        de.delete
      end
    end

    DiscussionTopic.unscoped.where(user_id: user.id).delete_all
    
    CommunicationChannel.where(user_id: user.id).each do |c|
      c.notification_policies.destroy_all
      c.delete
    end
    
    user.eportfolios.delete_all
    user.pseudonyms.each do |ps|
      ps.auditor_authentication_records.destroy_all
      ps.auditor_authentication_records.delete_all
      ps.session_persistence_tokens.destroy_all
    end

    user.pseudonyms.delete_all
    user.communication_channels.delete_all
    user.delete
  end
end

THREADS=10 RAILS_ENV=production bundle exec rake users:spam_clean