Ruby script to send auto-responses see http://chrismar035.com/2011/02/15/ruby-auto-responder-for-postfix-vmail

auto-responder-script.rb

require 'fileutils'
require 'rubygems'
require 'pony'


# Set absolute path for config file directory
conf_path = "/home/auto-responses"

#for each config file (autoresponder)
Dir.new(conf_path).each do |response_file|
  # don't act on this file or linux '.' listings
  unless response_file[0,1] == "." || response_file == "auto-response-script.rb"
    #create a file for reading
    file = File.new("#{conf_path}/#{response_file}")
    
    # get the last modified time of the current config file
    last_date = file.stat.mtime

    # e-mail address to respond from is first line
    address = file.gets.chomp
   
    #skip blank lines
    begin 
      line = file.gets
    end while line == "\n"

    # subject is next
    base_subject = "#{line.chomp} (Auto-Response)"

    #skip blank lines
    begin 
      line = file.gets
    end while line == "\n"

    # take all the rest of the lines as the message
    message = line
    while line = file.gets 
      message << line
    end

    # write parsed info to output (for log file)
    puts address
    #puts last_date
    #puts subject
    #puts message

    # split the e-mail address into user and domain to put into vmail path    
    user = address.split('@')[0]
    domain = address.split('@')[1]
    #puts user
    #puts domain

    # build the vmail path to the new mail message files
    mail_path = "/home/vmail/#{domain}/#{user}/new"
    
    #for each new mail file
    Dir.new(mail_path).each do |mail_file|
      #don't act on the linux '.' listings
      unless mail_file[0,1] == "."
        # get mail file for reading
        mail = File.new(mail_path + '/' + mail_file)
        
        #log mail filename and mod times (for debugging)
        puts mail_file
        puts "mail_file_time: #{mail.stat.mtime}"
        puts "conf_file_time: #{last_date}"
        
        # act only if mail file is newer
        if mail.stat.mtime > last_date
        
          # initialize flags for From and Subject lines in message
          found_from = false
          found_subject = false
          
          #get first line from email message
          line = mail.gets
          begin
            # regex to check if line starts with 'From:'
            # if so, store as from
            if line =~ /^From:/i && !found_from
              found_from = true
              from = line
            end
            
            # regex to check if line starts with 'Subject:'
            # if so, append the base_subject from above and store as subject
            if line =~ /^Subject:/i && !found_subject
              found_subject = true
              subject = "Re: #{line.chomp} - #{base_subject}"
            end
            
            #get next line
            line = mail.gets
          # loop over lines until both from AND subject are foud OR there are no more lines
          end while (!found_from && !found_subject) || line
          
          # use the base subject if couldn't find message subject
          subject = base_subject unless found_subject

          
          #puts "From line: #{from}"
          
          # take the From line and split on spaces
          # each 'word' which contains an @ (and isn't mailer-deamon) store into the to array
          to = Array.new
          from.split(' ').each do |name|
            if(name =~ /@/  && !(name =~ /MAILER.DAEMON/i))
              to << name 
            end
          end

          # create comma separated list of email addresses; stripping angle brackets
          to = to.join(',').gsub('<','').gsub('>','')

          # log to whom sending mail
          puts "Sending to: #{to}"
          
          # don't send mail to nobody
          unless to == "" || to == 'invalid@emailaddress.com'
            Pony.mail(:to => to, :from => address, :subject => subject, 
              :body => message )
          else
            puts "To is invalid"
          end
        else
          # log that the mail file is not newer than the conf file
          puts "From: #{mail_file} is not newer"
        end
        # separate the mail messages in the log
        puts "------------\n\n"
      end
    end
    
    # update the auto response file's mod time
    FileUtils.touch "#{conf_path}/#{response_file}"
  end
end