Identifiy and disable users that are in the list of users with invalid emails and do not have any purchases and are not active.

disable_users.rake

namespace :disable_users do

  desc 'Generates a csv file containing candidates for deletion'
  task :determine_candidates => :environment do
    logger = Logger.new('tmp/candidates.csv')

    users = 0
    candidates = 0

    { :invalid => :invalid_emails, :dns_err => :unresolvable_emails }.each_pair do |reason, input_file|
      File.read("tmp/#{input_file}.csv").each do |line|
        users += 1

        _, uuid, date, email = line.split(',')

        if user = User.find_by_uuid(uuid)
          date = DateTime.parse(date) if date
          last_active = [date, user.last_request_at].compact.max

          if user.purchases.blank? && (!last_active || last_active < 3.month.ago)
            logger.warn("#{reason},#{uuid},#{last_active},#{email}")

            candidates += 1
          end
        end
      end
    end

    puts "#{candidates} candidates / #{users} users"
  end

  desc 'Disable all users in the candidates.csv'
  task :delete_candidates => :environment do
    logger = Logger.new('log/deleted_candidates.csv')

    candidates = 0
    deleted    = 0

    File.read("tmp/candidates.csv").each do |line|
      candidates += 1

      reason, uuid, date, email = line.split(',')

      if user = User.find_by_uuid(uuid)
        user.delete_account(backup_user = true, notify_user = false)
        deleted += 1
      else
        logger.warn("User #{uuid} not found")
      end
      
      puts "processed candidate ##{candidates}"
    end

    logger.warn "#{deleted} deleted / #{candidates} candidates"
    puts        "#{deleted} deleted / #{candidates} candidates"
  end

end