Hello All,

I have a small web server application I've written in Python that goes and gets some data from a database system and returns it to the user as XML. That part works fine - I can run the Python web server application from the command line and I can have clients connect to it and get data back. At the moment, to run the web server I have to be logged in to our server as the administrator user and I have to manually start the web server. I want to have the web server automatically start on system start as a service and run in the background.

Using code from ActiveState's site and StackOverflow, I have a pretty good idea of how to go about creating a service, and I think I've got that bit sorted - I can install and start my web server as a Windows service. I can't, however, figure out how to stop the service again. My web server is created from a BaseHTTPServer:

Code:
server = BaseHTTPServer.HTTPServer(('', 8081), SIMSAPIServerHandler)
server.serve_forever()
The serve_forever() call, naturally enough, makes the web server sit in an infinite loop and wait for HTTP connections (or a ctrl-break keypress, not useful for a service). I get the idea from the example code above that your main() function is supposed to sit in an infinite loop and only break out of it when it comes accross a "stop" condition. My main calls serve_forever(). I have a SvcStop function:

Code:
def SvcStop(self):
	self.ReportServiceStatus(win32service.SERVICE_STOP_PENDING)
	exit(0)
Which seems to get called when I do "python myservice stop" from the command line (I can put a debug line in there that produces output to a file) but doesn't actually exit the whole service - subsequent calls to "python myservice start" gives me an error:

Error starting service: An instance of the service is already running.
and subsequent calls to stop gives me:

Error stopping service: The service cannot accept control messages at this time. (1061)
I think I need either some replacement for serve_forever (serve_until_stop_received, or whatever) or I need some way of modifying SvcStop so it stops the whole service.

Here's a full listing (I've trimmed includes/comments to save space):

Code:
    class SIMSAPIServerHandler(BaseHTTPServer.BaseHTTPRequestHandler):
    	def do_GET(self):
    		try:
    			reportTuple = self.path.partition("/")
    			if len(reportTuple) < 3:
    				return
    			if reportTuple[2] == "":
    				return
    			os.system("C:\\Programs\\SIMSAPI\\runCommandReporter.bat " + reportTuple[2])
    			f = open("C:\\Programs\\SIMSAPI\\out.xml", "rb")
    			self.send_response(200)
    			self.send_header('Content-type', "application/xml")
    			self.end_headers()
    			self.wfile.write(f.read())
    			f.close()
    			# The output from CommandReporter is simply dumped to out.xml, which we read, write to the user, then remove.
    			os.unlink("C:\\Programs\\SIMSAPI\\out.xml")
    			return
    		except IOError:
    			self.send_error(404,'File Not Found: %s' % self.path)
    			
    			
    			
    class SIMSAPI(win32serviceutil.ServiceFramework):
    	_svc_name_ = "SIMSAPI"
    	_svc_display_name_ = "A simple web server"
    	_svc_description_ = "Serves XML data produced by SIMS CommandReporter"
    	
    	def __init__(self, args):
    		win32serviceutil.ServiceFramework.__init__(self, args)
    		self.hWaitStop = win32event.CreateEvent(None, 0, 0, None)           
    		
    	def SvcStop(self):
    			self.ReportServiceStatus(win32service.SERVICE_STOP_PENDING)
    			exit(0)
    			
    	def SvcDoRun(self):
    		import servicemanager
    		servicemanager.LogMsg(servicemanager.EVENTLOG_INFORMATION_TYPE,servicemanager.PYS_SERVICE_STARTED,(self._svc_name_, '')) 
    		
    		self.timeout = 3000
    		
    		while 1:
    			server = BaseHTTPServer.HTTPServer(('', 8081), SIMSAPIServerHandler)
    			server.serve_forever()
    			
    def ctrlHandler(ctrlType):
    	return True
                      
    if __name__ == '__main__':
    	win32api.SetConsoleCtrlHandler(ctrlHandler, True)
    	win32serviceutil.HandleCommandLine(SIMSAPI)
--
David Hicks