rake task that generates a csv file containing invalid or unresolvable email addresses

validate_emails.rake

desc 'Generates a csv file containing invalid or unresolvable email addresses'
task :check_emails => :environment do
  logger = Logger.new('log/faulty_emails.csv')

  Account.find_each do |account|
    identifier = "#{account.uuid},#{[account.current_sign_in_at, account.updated_at].compact.max},#{account.email}"

    if !EmailUtils::Validator.valid?(account.email)
      logger.warn("invalid,#{identifier}")

    elsif !EmailUtils::Validator.resolvable_domain?(account.email)
      logger.warn("dns_err,#{identifier}")

    end

    puts "processed accounts up to ##{account.id}"  if account.id % 1_000 == 0
  end
end