Re: Pool Module Question (Now Proxy Server Question)

#!/usr/local/bin/python

import daemonize
import os, os.path, sys

LOG_DIR = '/var/log/usiecr2'
LOG_FILE = os.path.join(LOG_DIR, 'usiecr2.log')
ERR_FILE = os.path.join(LOG_DIR, 'usiecr2.err')
PID_FILE = '/var/run/usiecr2.pid'
CONF_FILE = '/usr/share/spyce/spyceconf.py'  # this dir CANNOT have a space in it or the split will fail below
SPYCE_DIR = '/usr/share/spyce'

# ensure the correct directories exist
if not os.path.exists(LOG_DIR):
  os.makedirs(LOG_DIR)

# first fork this process to a daemon
daemonize.startstop(stdout=LOG_FILE, stderr=ERR_FILE, pidfile=PID_FILE)

# change to the spyce directory
sys.path.append(SPYCE_DIR)
os.chdir(SPYCE_DIR)

# next call the spyce web server
# change argv to the new command we normally call to start the server
sys.argv = ('spyceCmd.py -l --conf ' + CONF_FILE).split(' ')
execfile(sys.argv[0])

#!/usr/local/bin/python

'''
    This module is used to fork the current process into a daemon.
    Almost none of this is necessary (or advisable) if your daemon 
    is being started by inetd. In that case, stdin, stdout and stderr are 
    all set up for you to refer to the network connection, and the fork()s 
    and session manipulation should not be done (to avoid confusing inetd). 
    Only the chdir() and umask() steps remain as useful.
    References:
        UNIX Programming FAQ
            1.7 How do I get my program to act like a daemon?
                http://www.erlenstar.demon.co.uk/unix/faq_2.html#SEC16
        Advanced Programming in the Unix Environment
            W. Richard Stevens, 1992, Addison-Wesley, ISBN 0-201-56317-7.

    History:
      2001/07/10 by Jurgen Hermann
      2002/08/28 by Noah Spurrier
      2003/02/24 by Clark Evans
      
      http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/66012
'''
import sys, os, time
from signal import SIGTERM

def deamonize(stdout='/dev/null', stderr=None, stdin='/dev/null',
              pidfile=None, startmsg = 'started with pid %s' ):
    '''
        This forks the current process into a daemon.
        The stdin, stdout, and stderr arguments are file names that
        will be opened and be used to replace the standard file descriptors
        in sys.stdin, sys.stdout, and sys.stderr.
        These arguments are optional and default to /dev/null.
        Note that stderr is opened unbuffered, so
        if it shares a file with stdout then interleaved output
        may not appear in the order that you expect.
    '''
    # Do first fork.
    try: 
        pid = os.fork() 
        if pid > 0: sys.exit(0) # Exit first parent.
    except OSError, e: 
        sys.stderr.write("fork #1 failed: (%d) %s\n" % (e.errno, e.strerror))
        sys.exit(1)
        
    # Decouple from parent environment.
    os.chdir("/") 
    os.umask(0) 
    os.setsid() 
    
    # Do second fork.
    try: 
        pid = os.fork() 
        if pid > 0: sys.exit(0) # Exit second parent.
    except OSError, e: 
        sys.stderr.write("fork #2 failed: (%d) %s\n" % (e.errno, e.strerror))
        sys.exit(1)
    
    # Open file descriptors and print start message
    if not stderr: stderr = stdout
    si = file(stdin, 'r')
    so = file(stdout, 'a+')
    se = file(stderr, 'a+', 0)
    pid = str(os.getpid())
    sys.stderr.write("\n%s\n" % startmsg % pid)
    sys.stderr.flush()
    if pidfile: file(pidfile,'w+').write("%s\n" % pid)
    
    # Redirect standard file descriptors.
    os.dup2(si.fileno(), sys.stdin.fileno())
    os.dup2(so.fileno(), sys.stdout.fileno())
    os.dup2(se.fileno(), sys.stderr.fileno())

def startstop(stdout='/dev/null', stderr=None, stdin='/dev/null',
              pidfile='pid.txt', startmsg = 'started with pid %s' ):
    if len(sys.argv) > 1:
        action = sys.argv[1]
        try:
            pf  = file(pidfile,'r')
            pid = int(pf.read().strip())
            pf.close()
        except IOError:
            pid = None
        if 'stop' == action or 'restart' == action:
            if not pid:
                mess = "Could not stop, pid file '%s' missing.\n"
                sys.stderr.write(mess % pidfile)
                if 'stop' == action:
                    sys.exit(1)
                action = 'start'
                pid = None
            else:
               try:
                  while 1:
                      os.kill(pid,SIGTERM)
                      time.sleep(1)
               except OSError, err:
                  err = str(err)
                  if err.find("No such process") > 0:
                      os.remove(pidfile)
                      if 'stop' == action:
                          sys.exit(0)
                      action = 'start'
                      pid = None
                  else:
                      print str(err)
                      sys.exit(1)
            time.sleep(5)

        if 'start' == action:
            if pid:
                mess = "Start aborded since pid file '%s' exists.\n"
                sys.stderr.write(mess % pidfile)
                sys.exit(1)
            deamonize(stdout,stderr,stdin,pidfile,startmsg)
            return
    print "usage: %s start|stop|restart" % sys.argv[0]
    sys.exit(2)

def test():
    '''
        This is an example main function run by the daemon.
        This prints a count and timestamp once per second.
    '''
    sys.stdout.write ('Message to stdout...')
    sys.stderr.write ('Message to stderr...')
    c = 0
    while 1:
        sys.stdout.write ('%d: %s\n' % (c, time.ctime(time.time())) )
        sys.stdout.flush()
        c = c + 1
        time.sleep(1)

if __name__ == "__main__":
    startstop(stdout='/tmp/deamonize.log',
              pidfile='/tmp/deamonize.pid')
    test()