Event when machine has been locked/unlocked (Electron Windows)

Question

So i have some tasks that i need to be notified when the user locks their machine. This is in order to pause those tasks. Equally i need to know when the machine has been successfully unlocked in order to resume said tasks. This is purely for a Windows only function so doesn't need to be cross-platform.

Ive looked through the Electron docs and found this about the powerMonitor API's however it only has events for suspend and resume. I assume they refer to the machine going to sleep as locking and un-locking does not trigger them on my machine (Win 10).

I know very little of how core Windows works, with its messages/event system. However i have found this which lists information about the WM_WTSSESSION_CHANGE which seems to be what i need. Notably the WTS_SESSION_LOCK (0x7) and WTS_SESSION_UNLOCK (0x8) status codes.

However i can't find a way either with electron or NodeJS directly to listen to Windows messages.

Any advice on the problem would be greatly appreciated. Thanks

Answer 1

Just in case someone ends up on this old question, powerMonitor now supports two events for this: lock-screen and unlock-screen, so you can just (in the main process):

const {powerMonitor} = require("electron");

powerMonitor.addListener('lock-screen', () => {
  // Screen is locked, do something
});

powerMonitor.addListener('unlock-screen', () => {
  // Screen is unlocked, do something else
});