UDP log receive script

udplogreceiver.ini

[web01]
port=5141
logfile=/var/log/web01.log

udplogreceiver.py

#!/usr/bin/python

configfile='/usr/local/etc/udplogreceiver.ini'

import ConfigParser
import select
import signal
import socket
import sys
import threading
import time                                                                                                                                                                                                                                  
                                                                                                                                                                                                                                             
class udplogreceiver(threading.Thread):                                                                                                                                                                                                      
  def __init__(self, name, port, logfile):                                                                                                                                                                                                   
    threading.Thread.__init__(self)                                                                                                                                                                                                          
    self.name = name                                                                                                                                                                                                                         
    self.port = port                                                                                                                                                                                                                         
    self.logfile = logfile                                                                                                                                                                                                                   
                                                                                                                                                                                                                                             
  def run(self):                                                                                                                                                                                                                             
    self.log = open(self.logfile,"a")                                                                                                                                                                                                        
    self.sock = socket.socket( socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP )                                                                                                                                                       
    self.sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)                                                                                                                                                                          
    self.sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)                                                                                                                                                                          
    self.sock.bind( ('',self.port) )                                                                                                                                                                                                         
    self.sock.setblocking(0)                                                                                                                                                                                                                 
                                                                                                                                                                                                                                             
    while True:                                                                                                                                                                                                                              
      result = select.select( [self.sock], [], [] )                                                                                                                                                                                          
      msg = result[0][0].recv( 8196 )                                                                                                                                                                                                        
      self.log.write(msg)                                                                                                                                                                                                                    
      self.log.flush()                                                                                                                                                                                                                       
                                                                                                                                                                                                                                             
  def stop(self):                                                                                                                                                                                                                            
    self.log.close()                                                                                                                                                                                                                         
    self.sock.close()                                                                                                                                                                                                                        
                                                                                                                                                                                                                                             
  def reload(self):                                                                                                                                                                                                                          
    self.log.close()                                                                                                                                                                                                                         
    self.log = open(self.logfile,"a")

def reload(*args):
  print "\nSIGHUP received, reloading\n"
  for thread in threads:
    thread.reload()

def cleanupandexit(signum,*args):
  if signum == 2:
    print "\nSIGINT received, exiting\n"
  elif signum == 15:
    print "\nSIGTERM received, exiting\n"
  else:
    print "Exiting"
  for thread in threads:
    thread.stop()
  sys.exit(0)

def main():
  parser = ConfigParser.SafeConfigParser()
  parser.read(configfile)
  sections = parser.sections()
  if len(sections) == 0:
    sys.stderr.write("Configfile %s does not exist or is empty\n" % configfile)
    sys.exit(1)

  global threads
  threads = []
  for section in parser.sections():
    try:
      port = int(parser.get(section,'port'))
    except ConfigParser.NoOptionError:
      sys.stderr.write("Port not set for section %s\n" % section)
      sys.exit(2)
    try:
      logfile = parser.get(section,'logfile')
    except ConfigParser.NoOptionError:
      sys.stderr.write("Logfile option not set for section %s\n" % section)
      sys.exit(3)
    thread = udplogreceiver(section, port, logfile)
    thread.daemon = True
    threads.append(thread)

  for thread in threads:
    thread.start()

  while True:
    try:
      pass
      time.sleep(1)
    except KeyboardInterrupt:
      cleanupandexit(2)

signal.signal(signal.SIGHUP,reload)
signal.signal(signal.SIGTERM,cleanupandexit)
signal.signal(signal.SIGINT,cleanupandexit)
main()