agent-winservice: add file logging

agent-winservice.py

-import win32serviceutil
-import win32service
-import win32event
+import logging
+import os
 import servicemanager
 import socket
+import win32event
+import win32service
+import win32serviceutil
 
 from agent import main as agent_main, reactor
 
+logger = logging.getLogger()
+fh = logging.FileHandler(
+    os.path.join(os.path.dirname(__file__), "agent-service.log"))
+formatter = logging.Formatter(
+    "%(asctime)s - %(name)s [%(levelname)s] %(message)s")
+fh.setFormatter(formatter)
+logger.addHandler(fh)
+logger.info("%s loaded", __file__)
+
 
 class AppServerSvc (win32serviceutil.ServiceFramework):
     _svc_name_ = "circle-agent"
@@ -20,11 +31,13 @@ class AppServerSvc (win32serviceutil.ServiceFramework):
         self.ReportServiceStatus(win32service.SERVICE_STOP_PENDING)
         win32event.SetEvent(self.hWaitStop)
         reactor.stop()
+        logger.info("%s stopped", __file__)
 
     def SvcDoRun(self):
         servicemanager.LogMsg(servicemanager.EVENTLOG_INFORMATION_TYPE,
                               servicemanager.PYS_SERVICE_STARTED,
                               (self._svc_name_, ''))
+        logger.info("%s starting", __file__)
         agent_main()