# A Demo of a service that takes advantage of the additional notifications
# available in later Windows versions.
# Note that all output is written as event log entries - so you must install
# and start the service, then look at the event log for messages as events
# are generated.
# Events are generated for USB device insertion and removal, power state
# changes and hardware profile events - so try putting your computer to
# sleep and waking it, inserting a memory stick, etc then check the event log
import win32serviceutil, win32service
import win32event
import servicemanager
# Most event notification support lives around win32gui
import win32gui, win32gui_struct, win32con
GUID_DEVINTERFACE_USB_DEVICE = "{A5DCBF10-6530-11D2-901F-00C04FB951ED}"
class EventDemoService(win32serviceutil.ServiceFramework):
_svc_name_ = "PyServiceEventDemo"
_svc_display_name_ = "Python Service Event Demo"
_svc_description_ = "Demonstrates a Python service which takes advantage of the extra notifications"
def __init__(self, args):
win32serviceutil.ServiceFramework.__init__(self, args)
self.hWaitStop = win32event.CreateEvent(None, 0, 0, None)
# register for a device notification - we pass our service handle
# instead of a window handle.
filter = win32gui_struct.PackDEV_BROADCAST_DEVICEINTERFACE(
GUID_DEVINTERFACE_USB_DEVICE)
self.hdn = win32gui.RegisterDeviceNotification(self.ssh, filter,
win32con.DEVICE_NOTIFY_SERVICE_HANDLE)
# Override the base class so we can accept additional events.
def GetAcceptedControls(self):
# say we accept them all.
rc = win32serviceutil.ServiceFramework.GetAcceptedControls(self)
rc |= win32service.SERVICE_ACCEPT_PARAMCHANGE \
| win32service.SERVICE_ACCEPT_NETBINDCHANGE \
| win32service.SERVICE_CONTROL_DEVICEEVENT \
| win32service.SERVICE_ACCEPT_HARDWAREPROFILECHANGE \
| win32service.SERVICE_ACCEPT_POWEREVENT \
| win32service.SERVICE_ACCEPT_SESSIONCHANGE
return rc
# All extra events are sent via SvcOtherEx (SvcOther remains as a
# function taking only the first args for backwards compat)
def SvcOtherEx(self, control, event_type, data):
# This is only showing a few of the extra events - see the MSDN
# docs for "HandlerEx callback" for more info.
if control == win32service.SERVICE_CONTROL_DEVICEEVENT:
info = win32gui_struct.UnpackDEV_BROADCAST(data)
msg = "A device event occurred: %x - %s" % (event_type, info)
elif control == win32service.SERVICE_CONTROL_HARDWAREPROFILECHANGE:
msg = "A hardware profile changed: type=%s, data=%s" % (event_type, data)
elif control == win32service.SERVICE_CONTROL_POWEREVENT:
msg = "A power event: setting %s" % data
elif control == win32service.SERVICE_CONTROL_SESSIONCHANGE:
# data is a single elt tuple, but this could potentially grow
# in the future if the win32 struct does
msg = "Session event: type=%s, data=%s" % (event_type, data)
else:
msg = "Other event: code=%d, type=%s, data=%s" \
% (control, event_type, data)
servicemanager.LogMsg(
servicemanager.EVENTLOG_INFORMATION_TYPE,
0xF000, # generic message
(msg, '')
)
def SvcStop(self):
self.ReportServiceStatus(win32service.SERVICE_STOP_PENDING)
win32event.SetEvent(self.hWaitStop)
def SvcDoRun(self):
# do nothing at all - just wait to be stopped
win32event.WaitForSingleObject(self.hWaitStop, win32event.INFINITE)
# Write a stop message.
servicemanager.LogMsg(
servicemanager.EVENTLOG_INFORMATION_TYPE,
servicemanager.PYS_SERVICE_STOPPED,
(self._svc_name_, '')
)
if __name__=='__main__':
win32serviceutil.HandleCommandLine(EventDemoService)
|