module Sisimai::Lhost::Courier

Sisimai::Lhost::Courier parses a bounce email which created by Courier MTA. Methods in the module are called from only Sisimai::Message.

Constants

Indicators

www.courier-mta.org/courierdsn.html

MessagesOf
ReBackbone
StartingOf

Public Class Methods

description() click to toggle source
# File lib/sisimai/lhost/courier.rb, line 142
def description; return 'Courier MTA'; end
make(mhead, mbody) click to toggle source

Parse bounce messages from Courier MTA @param [Hash] mhead Message headers of a bounce email @param [String] mbody Message body of a bounce email @return [Hash] Bounce data list and message/rfc822 part @return [Nil] it failed to parse or the arguments are missing

# File lib/sisimai/lhost/courier.rb, line 32
def make(mhead, mbody)
  match  = 0
  match += 1 if mhead['from'].include?('Courier mail server at ')
  match += 1 if mhead['subject'] =~ /(?:NOTICE: mail delivery status[.]|WARNING: delayed mail[.])/
  if mhead['message-id']
    # Message-ID: <courier.4D025E3A.00001792@5jo.example.org>
    match += 1 if mhead['message-id'] =~ /\A[<]courier[.][0-9A-F]+[.]/
  end
  return nil unless match > 0

  require 'sisimai/rfc1894'
  fieldtable = Sisimai::RFC1894.FIELDTABLE
  permessage = {}     # (Hash) Store values of each Per-Message field

  dscontents = [Sisimai::Lhost.DELIVERYSTATUS]
  emailsteak = Sisimai::RFC5322.fillet(mbody, ReBackbone)
  bodyslices = emailsteak[0].split("\n")
  readslices = ['']
  readcursor = 0      # (Integer) Points the current cursor position
  recipients = 0      # (Integer) The number of 'Final-Recipient' header
  commandtxt = ''     # (String) SMTP Command name begin with the string '>>>'
  v = nil

  while e = bodyslices.shift do
    # Read error messages and delivery status lines from the head of the email
    # to the previous line of the beginning of the original message.
    readslices << e # Save the current line for the next loop

    if readcursor == 0
      # Beginning of the bounce message or message/delivery-status part
      if e.include?(StartingOf[:message][0]) || e.include?(StartingOf[:message][1])
        readcursor |= Indicators[:deliverystatus]
        next
      end
    end
    next if (readcursor & Indicators[:deliverystatus]) == 0
    next if e.empty?

    if f = Sisimai::RFC1894.match(e)
      # "e" matched with any field defined in RFC3464
      next unless o = Sisimai::RFC1894.field(e)
      v = dscontents[-1]

      if o[-1] == 'addr'
        # Final-Recipient: rfc822; kijitora@example.jp
        # X-Actual-Recipient: rfc822; kijitora@example.co.jp
        if o[0] == 'final-recipient'
          # Final-Recipient: rfc822; kijitora@example.jp
          if v['recipient']
            # There are multiple recipient addresses in the message body.
            dscontents << Sisimai::Lhost.DELIVERYSTATUS
            v = dscontents[-1]
          end
          v['recipient'] = o[2]
          recipients += 1
        else
          # X-Actual-Recipient: rfc822; kijitora@example.co.jp
          v['alias'] = o[2]
        end
      elsif o[-1] == 'code'
        # Diagnostic-Code: SMTP; 550 5.1.1 <userunknown@example.jp>... User Unknown
        v['spec'] = o[1]
        v['diagnosis'] = o[2]
      else
        # Other DSN fields defined in RFC3464
        next unless fieldtable[o[0]]
        v[fieldtable[o[0]]] = o[2]

        next unless f == 1
        permessage[fieldtable[o[0]]] = o[2]
      end
    else
      # The line does not begin with a DSN field defined in RFC3464
      if cv = e.match(/\A[>]{3}[ ]+([A-Z]{4})[ ]?/)
        # Your message to the following recipients cannot be delivered:
        #
        # <kijitora@example.co.jp>:
        #    mx.example.co.jp [74.207.247.95]:
        # >>> RCPT TO:<kijitora@example.co.jp>
        # <<< 550 5.1.1 <kijitora@example.co.jp>... User Unknown
        #
        next unless commandtxt.empty?
        commandtxt = cv[1]
      else
        # Continued line of the value of Diagnostic-Code field
        next unless readslices[-2].start_with?('Diagnostic-Code:')
        next unless cv = e.match(/\A[ \t]+(.+)\z/)
        v['diagnosis'] << ' ' << cv[1]
        readslices[-1] = 'Diagnostic-Code: ' << e
      end
    end
  end
  return nil unless recipients > 0

  dscontents.each do |e|
    # Set default values if each value is empty.
    permessage.each_key { |a| e[a] ||= permessage[a] || '' }
    e['command'] ||= commandtxt || ''
    e['diagnosis'] = Sisimai::String.sweep(e['diagnosis']) || ''

    MessagesOf.each_key do |r|
      # Verify each regular expression of session errors
      next unless MessagesOf[r].any? { |a| e['diagnosis'].include?(a) }
      e['reason'] = r
      break
    end
  end

  return { 'ds' => dscontents, 'rfc822' => emailsteak[1] }
end