simplified collections with duck typing

gistfile1.rb

namespace :assets do
  desc "fetch descriptions for youtube videos without descriptions"
  task yt_fetch_description: :environment do
    BsuDescriptionUpdater.new(YtChanReg, FbPgeReg, IgUsrReg).update_all
  end
end

class BsuDescriptionUpdater
  def initialize(*source_klasses)
    @source_klasses = source_klasses.map { |src| DescriptionUpdater.new(src) }
  end

  def update_all
    binding.pry
    @source_klasses.sample.update
  #rescue Exception => e
    #puts e.message
    #puts e.backtrace.inspect
    #sleep(10)
    #retry
  end

  class DescriptionUpdater
    def initialize(source_klass)
      @source_klass = source_klass
    end

    def update
      total = @source_klass.where(description: nil).count

      @source_klass.where(description: nil).find_each do |reg|
        total -= 1
        puts "#{total} #{@source_class.name} descriptions to fetch..."
        reg.update_description
      end
    end
  end
end