imapでfromが特定アドレスにマッチしたメールだけを削除する

mail_del_imap.rb

# -*- encoding: utf-8 -*-

require 'net/imap'
require 'kconv'

SVR='sample.server.com'
USR='user'
PWD='pppppp'
ADR='[email protected]'

class Net::IMAP::Envelope
  def mail_address_formatted(value)
    return nil unless ["from", "sender", "reply_to", "to"].include?(value)
    self.__send__(value)[0].mailbox + "@" + self.__send__(value)[0].host
  end
end

imap = Net::IMAP.new(SVR)
imap.login(USR,PWD)
imap.select('INBOX')
imap.search(['UNSEEN']).each do |msg_id|
  envelope = imap.fetch(msg_id, "ENVELOPE")[0].attr["ENVELOPE"]
  from = envelope.mail_address_formatted("from")
  puts "#{msg_id}:#{from}:#{envelope.subject.toutf8}"
  if from == ADR
    puts "delete"
    imap.store(msg_id, "+FLAGS", [:Deleted])
  end
end
imap.expunge