I am sketching the architecture for a set of programs that share various interrelated objects stored in a database. I want one of the programs to act as a service which provides a higher level interface for operations on these objects, and the other programs to access the objects through that service.
I am currently aiming for Python and the Django framework as the technologies to implement that service with. I'm pretty sure I figure how to daemonize the Python program in Linux. However, it is an optional spec item that the system should support Windows. I have little experience with Windows programming and no experience at all with Windows services.
Is it possible to run a Python programs as a Windows service (i. e. run it automatically without user login)? I won't necessarily have to implement this part, but I need a rough idea how it would be done in order to decide whether to design along these lines.
Edit: Thanks for all the answers so far, they are quite comprehensive. I would like to know one more thing: How is Windows aware of my service? Can I manage it with the native Windows utilities? What is the equivalent of putting a start/stop script in /etc/init.d?
This is a basic skeleton for a simple service:
import win32serviceutil import win32service import win32event import servicemanager import socket class AppServerSvc (win32serviceutil.ServiceFramework): _svc_name_ = "TestService" _svc_display_name_ = "Test Service" def __init__(self,args): win32serviceutil.ServiceFramework.__init__(self,args) self.hWaitStop = win32event.CreateEvent(None,0,0,None) socket.setdefaulttimeout(60) def SvcStop(self): self.ReportServiceStatus(win32service.SERVICE_STOP_PENDING) win32event.SetEvent(self.hWaitStop) def SvcDoRun(self): servicemanager.LogMsg(servicemanager.EVENTLOG_INFORMATION_TYPE, servicemanager.PYS_SERVICE_STARTED, (self._svc_name_,'')) self.main() def main(self): pass if __name__ == '__main__': win32serviceutil.HandleCommandLine(AppServerSvc)
Your code would go in the
main() method—usually with some kind of infinite loop that might be interrupted by checking a flag, which you set in the
Although I upvoted the chosen answer a couple of weeks back, in the meantime I struggled a lot more with this topic. It feels like having a special Python installation and using special modules to run a script as a service is simply the wrong way. What about portability and such?
I stumbled across the wonderful Non-sucking Service Manager, which made it really simple and sane to deal with Windows Services. I figured since I could pass options to an installed service, I could just as well select my Python executable and pass my script as an option.
I have not yet tried this solution, but I will do so right now and update this post along the process. I am also interested in using virtualenvs on Windows, so I might come up with a tutorial sooner or later and link to it here.