OnStop not called intentionaly when system (Win7) shuts down?

[peterkottas]

OnStop not called intentionaly when system (Win7) shuts down?

[MontyGvMC]

I have found a question on StackOverflow: Killing gracefully a .NET Core daemon running on Linux

Whenever there is a need for being notified when the system shutsdown this line helps:

AssemblyLoadContext.Default.Unloading += MethodInvokedOnSigTerm

I used it in MyService : IMicroservice to call the Stop() method manually

[PeterKottas]

Hey mate, just came back from holidays and reading your issue. I must say I am not exactly sure how this should work. It feels like the stop should be called only when the service is stopped. Shutting down the pc is maybe not stopping per say. More like a termination. It might make sense to add another callback (OnShutdown) and use the solution that you proposed to call it. Or just call OnStop instead? Just thinking out loud here TBH.

[dasMulli]

This would be possible in a custom state machine instead of IWin32Service.. I haven't had any request or the need for a shutdown event so I haven't implemented any convenience API for it. But the event can be registered for in windows' service management system. ServiceBase has an OnShutdown() function that can be used for this.

[z3r0privacy]

I stumbled upon this issue a few days ago since I needed the hook on Shutdown too. So I gave it a try today and thanks to the good work of @dasMulli this was actually fairly easy to accomplish.

It's not a perfect solution but it works and is a good point to go.

All you need to do is:

• Create an interface called IShutdownableWin32Service or something like that, which extends IWin32Service and add a method void Shutdown();
• Change InnerService class to implement IShutdownableWin32Service and implement the missing method like the others are implemented already. You also want to add an argument for the shutdown action to the constructor
• Add public Action<SERVICE> OnServiceShutdown { get; set; } in the HostConfiguration class.
• In the ServiceRunner class you need to pass an argument for the new shutdown argument. Again, do this like the Stop(config) method using the new created action in the previous step.
• Create the custom state machine. For this, copy the SimpleServiceStateMachine from here and name it ShutdownableServiceStateMachine. Apply a few changes:
  • Change the type of serviceImplementation to IShutdownableWin32Service. Don't forget to change this in the constructor too.
  • In the OnStart method, change the second line in the try block to statusReportCallback(ServiceState.Running, ServiceAcceptedControlCommandsFlags.Stop | ServiceAcceptedControlCommandsFlags.Shutdown, win32ExitCode: 0, waitHint: 0);
• In the OnCommand method, add the following.

else if (command == ServiceControlCommand.Shutdown)
{
    try
    {
        statusReportCallback(ServiceState.StopPending, ServiceAcceptedControlCommandsFlags.None, win32ExitCode: 0, waitHint: 3000); //this is probably too much, see note down below
        serviceImplementation.Shutdown();
    }
    catch { }
    finally
    {
        statusReportCallback(ServiceState.Stopped, ServiceAcceptedControlCommandsFlags.None, win32ExitCode: 0, waitHint: 0);
    }
}

• Back in the ServiceRunner class change the line where the Win32ServiceHost is initialized (in method ConfigureService) to var serviceHost = new Win32ServiceHost(config.Name, new ShutdownableServiceStateMachine(testService));
• Add a OnShutdown method in the ServiceConfigurator class so you can use it from the configuration code.

Note: This should do the trick and also covers a system restart. Please note the remarks mentioned at MSDN about the SERVICE_CONTROL_SHUTDOWN control.

[PeterKottas]

Fixed by https://github.com/PeterKottas/DotNetCore.WindowsService/releases/tag/v2.0.7. Feel free to reopen if you find any issues with the current solution.