Python Deamon + Service classes

Deamon.py

import atexit
import os
import signal
import sys
import time

__author__ = 'fundor333'


class Daemon:
    """A generic daemon class.

    Usage: subclass the daemon class and override the run() method."""

    def __init__(self, pidfile):
        self.pidfile = pidfile

    def daemonize(self):
        try:
            pid = os.fork()
            if pid > 0:
                # exit first parent
                sys.exit(0)
        except OSError as err:
            sys.stderr.write('fork #1 failed: {0}\n'.format(err))
            sys.exit(1)

        # decouple from parent environment
        os.chdir('/')
        os.setsid()
        os.umask(0)

        # do second fork
        try:
            pid = os.fork()
            if pid > 0:
                # exit from second parent
                sys.exit(0)
        except OSError as err:
            sys.stderr.write('fork #2 failed: {0}\n'.format(err))
            sys.exit(1)

        # redirect standard file descriptors
        sys.stdout.flush()
        sys.stderr.flush()
        si = open(os.devnull, 'r')
        so = open(os.devnull, 'a+')
        se = open(os.devnull, 'a+')

        os.dup2(si.fileno(), sys.stdin.fileno())
        os.dup2(so.fileno(), sys.stdout.fileno())
        os.dup2(se.fileno(), sys.stderr.fileno())

        # write pidfile
        atexit.register(self.delpid)

        pid = str(os.getpid())
        with open(self.pidfile, 'w+') as f:
            f.write(pid + '\n')

    def delpid(self):
        os.remove(self.pidfile)

    def start(self):
        """Start the daemon."""

        # Check for a pidfile to see if the daemon already runs
        try:
            with open(self.pidfile, 'r') as pf:

                pid = int(pf.read().strip())
        except IOError:
            pid = None

        if pid:
            message = "pidfile {0} already exist. " + \
                      "Daemon already running?\n"
            sys.stderr.write(message.format(self.pidfile))
            sys.exit(1)

        # Start the daemon
        self.daemonize()
        self.run()

    def stop(self):
        """Stop the daemon."""

        # Get the pid from the pidfile
        try:
            with open(self.pidfile, 'r') as pf:
                pid = int(pf.read().strip())
        except IOError:
            pid = None

        if not pid:
            message = "pidfile {0} does not exist. " + \
                      "Daemon not running?\n"
            sys.stderr.write(message.format(self.pidfile))
            return  # not an error in a restart

        # Try killing the daemon process
        try:
            while 1:
                os.kill(pid, signal.SIGTERM)
                time.sleep(0.1)
        except OSError as err:
            e = str(err.args)
            if e.find("No such process") > 0:
                if os.path.exists(self.pidfile):
                    os.remove(self.pidfile)
            else:
                print(str(err.args))
                sys.exit(1)

    def restart(self):
        """Restart the daemon."""
        self.stop()
        self.start()

    def run(self):
        raise NotImplemented

Service.py

from os.path import splitext, abspath
from sys import modules

import win32api
import win32event
import win32service
import win32serviceutil


class Service(win32serviceutil.ServiceFramework):
    _svc_name_ = '_unNamed'
    _svc_display_name_ = '_Service Template'

    def __init__(self, *args):
        win32serviceutil.ServiceFramework.__init__(self, *args)
        self.log('init')
        self.stop_event = win32event.CreateEvent(None, 0, 0, None)

    def log(self, msg):
        import servicemanager

        servicemanager.LogInfoMsg(str(msg))

    def sleep(self, sec):
        win32api.Sleep(sec * 1000, True)

    def SvcDoRun(self):
        self.ReportServiceStatus(win32service.SERVICE_START_PENDING)
        try:
            self.ReportServiceStatus(win32service.SERVICE_RUNNING)
            self.log('start')
            self.start()
            self.log('wait')
            win32event.WaitForSingleObject(self.stop_event, win32event.INFINITE)
            self.log('done')
        except Exception as x:
            self.log('Exception : %s' % x)
            self.SvcStop()

    def SvcStop(self):
        self.ReportServiceStatus(win32service.SERVICE_STOP_PENDING)
        self.log('stopping')
        self.stop()
        self.log('stopped')
        win32event.SetEvent(self.stop_event)
        self.ReportServiceStatus(win32service.SERVICE_STOPPED)

    # to be overridden
    def start(self):
        pass

    # to be overridden
    def stop(self):
        pass

    def run(self, name, display_name=None, stay_alive=True):
        """ Install and  Start (auto) a Service

            cls : the class (derived from Service) that implement the Service
            name : Service name
            display_name : the name displayed in the service manager
            stay_alive : Service will stop on logout if False
        """
        self._svc_name_ = name
        self._svc_display_name_ = display_name or name
        try:
            module_path = modules[self.__module__].__file__
        except AttributeError:
            # maybe py2exe went by
            from sys import executable

            module_path = executable
        module_file = splitext(abspath(module_path))[0]
        self._svc_reg_class_ = '%s.%s' % (module_file, self.__name__)
        if stay_alive: win32api.SetConsoleCtrlHandler(lambda x: True, True)
        try:
            win32serviceutil.InstallService(
                self._svc_reg_class_,
                self._svc_name_,
                self._svc_display_name_,
                startType=win32service.SERVICE_AUTO_START
            )
            print('Install ok')
            win32serviceutil.StartService(
                self._svc_name_
            )
            print('Start ok')
        except Exception as x:
            print(str(x))


from winservice import Service


class Test(Service):
    def start(self):
        self.runflag = True
        while self.runflag:
            self.sleep(10)
            self.log("I'm alive ...")

    def stop(self):
        self.runflag = False
        self.log("I'm done")


startservice(Test, 'aTest', 'Python Service Test')