#
# send bulk mail quickly by injecting it directly into 
# the maildrop
#
# this works in our postfix environment, YMMV
# you will have to take some steps for 'nobody' to be allowed to 
# start/stop postfix (write a SUID root wrapper, basically).
# if you have no clue about the implications DON'T DO IT!
#
# 2000-11-03, stefan@epy.co.at
#

import os, time, threading

startcommand   = '/Zope/mybin/postfixwrapper start'
stopcommand    = '/Zope/mybin/postfixwrapper stop'
lockfile       = '/Zope/var/bulkmailhack.lock'
injectcommand  = '/usr/sbin/sendmail -t -oi -f%s'
mailtemplate   = 'From: %s\nTo: %s\nPrecedence: bulk\nSubject: %s\n%s\n'


def sendMail( mailfrom, addrlist, subject, body, detached=1 ):
  if detached:
    t = threading.Thread( None, sender_thread, None, (mailfrom, addrlist, subject, body) )
    t.start()
    return
  else:
    ts = time.time()
    sender_thread( mailfrom, addrlist, subject, body )
    tr = time.time() - ts
    return (tr, len(addrlist)/tr)


def sender_thread( mailfrom, addrlist, subject, body ):
  stop_mta()
  for mailto in addrlist:
    p = os.popen( injectcommand % (mailfrom), 'w', 1 )
    p.write( mailtemplate % (mailfrom, mailto, subject, body) )
    p.close()
  start_mta()


def stop_mta():
  while 1:
    try: 
      os.stat( lockfile )
    except: 
      l = open( lockfile, 'wt' )
      l.write( 'remove this file if the bulkmailhack appears to hang' )
      l.close()
      os.system( stopcommand )
      time.sleep( 5 )
      return 
    time.sleep( 15 )


def start_mta():
  try: 
    os.unlink( lockfile )
  except: 
    pass
  os.system( startcommand )