Mail delivery time (nagios check)

check_delivery_time.py

import optparse
import json
import smtplib
import sys
import time
import email.utils
import random
import string
import os.path
import os
import traceback
from socket import gethostname
from email.mime.text import MIMEText
from email import message_from_file

CONFIGFILE = "/path/to/config.json"

if __name__ == "__main__":
  try:
    parser = optparse.OptionParser(usage="Usage: %prog [options]")
    parser.add_option("--config", dest="config", type="str", help="Config file path", default="")
    parser.add_option("-w", "--warning", dest="warning", type="float", help="Delivery time before warning")
    parser.add_option("-c", "--critical", dest="critical", type="float", help="Delivery time before critical")
    
    options, args = parser.parse_args()
    
    global CONFIG
    CONFIG = None
    
    if options.config != "":
      with open(options.config) as f:
        CONFIG = json.load(f)
    else:
      with open(CONFIGFILE) as f:
        CONFIG = json.load(f)
    
    hostname = gethostname() + "." + CONFIG["domain"]
    
    if options.warning > options.critical:
      raise Exception("Warning time cannot be greater than critical time.")
    
    times = []
    for root, dirs, files in os.walk(os.path.join(CONFIG["maildir"], "Maildir", "new")):
      for name in files:
        filename = os.path.join(root, name)
        stats = os.stat(filename)
        with open(filename) as emailf:
          msg = message_from_file(emailf)
        if msg["Subject"].lower().strip() == hostname.lower().strip():
          body = msg.get_payload()
          starttime = float(body.strip())
          times.append((starttime, stats.st_ctime))
          os.remove(filename)
    
    if len(times) == 0:
      print "No messages found."
      sys.exit(3)
    times.sort(key=lambda t: t[0])
    latest = times[-1]
    start = latest[0]
    end = latest[1]
    deliverytime = end - start
    print "Delivery time: %s" % deliverytime
    if deliverytime > options.critical:
      sys.exit(2)
    elif deliverytime > options.warning:
      sys.exit(1)
    else:
      sys.exit(0)
  except Exception, e:
    traceback.print_exc()
    print str(e)
    sys.exit(3)

deliverytimeconfig.json

{
  "servers" : ["smtp01.example.com", "smtp02.example.com"],
  "domain" : "example.com",
  "smtp_user" : "deliverytimer@example.com",
  "smtp_pass" : "tOtAlLySeCuRePaSsWoRd!1",
  "from_header" : "deliverytimer@example.com",
  "to_header" : "deliverytimer@example.com",
  "mail_from" : "deliverytimer@example.com",
  "rcpt_to" : "deliverytimer@example.com",
  "maildir" : "/path/to/maildir"
}

deliverytimemailsender.py

import optparse
import json
import smtplib
import sys
import time
import email.utils
import random
import string
from email.mime.text import MIMEText

CONFIGFILE = "/path/to/config.json"

def debugwrite(s):
  if DEBUG:
    sys.stderr.write(s)

def dumpRecipientsRefused(e):
  '''Takes in an SMTPRecipientsRefused exception and
pretty prints it if verbosity is set.'''
  if DEBUG:
    sys.stderr.write("Recipient Address Refused.\n")
    for k, v in e.recipients.items():
      sys.stderr.write("%s: %s (%s)\n" % (k, v[0], v[1]))

def sendMessage(smtp, messagestr, env_from_address, sendingtoaddress):
  '''Sends the given message to the given address,
using the given SMTP instance.'''
  debugwrite("Sending a message.\n")
  try:
    smtp.sendmail(env_from_address,
                  sendingtoaddress,
                  messagestr)
  except smtplib.SMTPRecipientsRefused, e:
    dumpRecipientsRefused(e)
  except smtplib.SMTPHeloError, e:
    debugwrite("SMTP server failed to respond correctly to HELO command.\n", 1)
  except smtplib.SMTPSenderRefused, e:
    debugwrite(
        "SMTP server rejected env-from address of %s.\n"
        % env_from_address, 1)
  except smtplib.SMTPDataError, e:
    debugwrite("Unknown STMP error.\n")

      
if __name__=="__main__":
  parser = optparse.OptionParser(usage="Usage: %prog [options] server")
  parser.add_option("--config", dest="config", type="str", help="Config file path", default="")
  parser.add_option("-d", "--debug", dest="debug", action="store_true", help="Debugging output.", default=False)
  
  options, args = parser.parse_args()
  
  global DEBUG
  DEBUG = options.debug
  
  global CONFIG
  if options.config != "":
    with open(options.config) as f:
      CONFIG = json.load(f)
  else:
    with open(CONFIGFILE) as f:
      CONFIG = json.load(f)
  
  for server in CONFIG["servers"]:
    smtp = smtplib.SMTP(server)
    if "smtp_user" in CONFIG and "smtp_pass" in CONFIG:
      smtp.login(CONFIG["smtp_user"], CONFIG["smtp_pass"])
    
    messageraw = str(time.time())
    message = MIMEText(messageraw)
    message["Date"] = email.utils.formatdate()
    message["From"] = CONFIG["from_header"]
    message["To"] = CONFIG["to_header"]
    message["Subject"] = server
   
    sendMessage(smtp, message.as_string(), CONFIG["mail_from"], CONFIG["rcpt_to"])

    smtp.close()