#!/usr/bin/env python
# coding: utf-8

from smtplib import SMTP, quotedata, CRLF, SMTPDataError
from email.MIMEMultipart import MIMEMultipart
from email.MIMEBase import MIMEBase
from email.MIMEText import MIMEText
from email import Encoders
from sys import stderr, stdout
import os
import sys

class ExtendedSMTP(SMTP):
  def data(self, msg):
    self.putcmd("data")
    (code,repl)=self.getreply()
    if self.debuglevel > 0 : print  stderr, "data:", (code, repl)
    if code != 354:
      raise SMTPDataError(code,repl)
    else:
      q = quotedata(msg)
      if q[-2:] != CRLF:
        q = q + CRLF
      q = q + "." + CRLF

      # begin modified send code
      chunk_size = 2048
      bytes_sent = 0

      while bytes_sent != len(q):
        chunk = q[bytes_sent:bytes_sent+chunk_size]
        self.send(chunk)
        bytes_sent += len(chunk)
        if hasattr(self, "callback"):
          self.callback(bytes_sent, len(q))
      # end modified send code

      (code,msg)=self.getreply()
      if self.debuglevel >0 : printstderr, "data:", (code,msg)
      return (code,msg)

def callback(progress, total):
  percent = 100. * progress / total
  stdout.write('\r')
  stdout.write("%s bytes sent of %s [%2.0f%%]" % (progress, total, percent))
  stdout.flush()
  if percent >= 100: stdout.write('\n')

def sendmail(subject):
  MAIL_FROM = 'mymail@qq.com'
  MAIL_TO = ['mymail@qq.com']
  BAK_DIR = '/path/to/bak/folder'

  msg = MIMEMultipart()
  msg['From'] = MAIL_FROM
  msg['Subject'] = subject

  msg.attach( MIMEText('test send attachment') )
  for filename in os.listdir(BAK_DIR):
    part = MIMEBase('application', "octet-stream")
    part.set_payload(open(os.path.join(BAK_DIR, filename),"rb").read() )
    Encoders.encode_base64(part)
    part.add_header('Content-Disposition', 'attachment; filename="%s"' % os.path.basename(filename))
    msg.attach(part)

  try:
    smtp = ExtendedSMTP()
    smtp.callback = callback
    smtp.connect('smtp.qq.com', 25)
    smtp.login('mymail', 'mypwd')
    smtp.sendmail(MAIL_FROM, MAIL_TO, msg.as_string())
    smtp.close()
    os.system('rm -f %s/*' % BAK_DIR)
  except Exception, e:
    print e

if __name__ == '__main__':
  if len(sys.argv) == 1:
    print 'Please specific a subject'
    print 'Usage: send_files <MAIL_SUBJECT>'
  else:
    sendmail(sys.argv[1])

$ chmod +x send_files

$ send_files '邮件标题'