Do not call ServiceBase.Stop(), fix some suppressions.

Author: CodeCasterNL

src/CodeCaster.WindowsServiceExtensions/GlobalSuppressions.cs

@@ -0,0 +1,8 @@
+// This file is used by Code Analysis to maintain SuppressMessage
+// attributes that are applied to this project.
+// Project-level suppressions either have no target or are given
+// a specific target and scoped to a namespace, type, member, etc.
+
+using System.Diagnostics.CodeAnalysis;
+
+[assembly: SuppressMessage("Interoperability", "CA1416:Validate platform compatibility", Justification = "We're a Windows Service, UseWindowsServiceExtensions() checks this", Scope = "namespaceanddescendants", Target = "~N:CodeCaster.WindowsServiceExtensions")]

src/CodeCaster.WindowsServiceExtensions/Lifetime/ExtendedWindowsServiceLifetime.cs

@@ -23,26 +23,11 @@ public class ExtendedWindowsServiceLifetime : HostApplicationStartupLifetime
         public ExtendedWindowsServiceLifetime(IServiceProvider serviceProvider, IHostEnvironment environment, IHostApplicationLifetime applicationLifetime, ILoggerFactory loggerFactory, IOptions<HostOptions> optionsAccessor)
             : base(serviceProvider, environment, applicationLifetime, loggerFactory, optionsAccessor)
         {
-            // Should not happen, here to keep the code analysis happy and the intention explicit.
-#pragma warning disable CA1416 // Validate platform compatibility
-            if (!OperatingSystem.IsWindows() || !WindowsServiceHelpers.IsWindowsService())
+            if (OperatingSystem.IsWindows() && WindowsServiceHelpers.IsWindowsService())
             {
-                const string methodName = nameof(WindowsServiceLifetimeHostBuilderExtensionsAdapter.UseWindowsServiceExtensions);
-
-                throw new PlatformNotSupportedException($"Windows Service needs to run on Windows. Remove the call to {methodName}()");
+                CanHandlePowerEvent = true;
+                CanHandleSessionChangeEvent = true;
             }
-
-            // Explicitly stop the service instead of just exiting the process.
-            // But this this will kill the application quickly, do other BackgroundServices get the time to exit nicely?
-            applicationLifetime.ApplicationStopping.Register(() =>
-            {
-                Logger.LogInformation("Application stopping, stopping service, exit code: {exitCode}", ExitCode);
-                
-                Stop();
-            });
-
-            CanHandlePowerEvent = true;
-            CanHandleSessionChangeEvent = true;
         }
 
         /// <summary>
@@ -80,19 +65,19 @@ protected override void OnSessionChange(SessionChangeDescription changeDescripti
             if (_hostedServices == null)
             {
                 Logger.LogDebug("No hosted services, returning");
-                
+
                 return;
             }
 
             // Forward the event to all registered I(PowerEventAware)HostedServices.
             foreach (var service in _hostedServices)
             {
-                Logger.LogDebug("Notifying service {service} about session change event: {sessionId}, {reason}", 
-                    service.GetType().FullName, 
-                    changeDescription.SessionId, 
+                Logger.LogDebug("Notifying service {service} about session change event: {sessionId}, {reason}",
+                    service.GetType().FullName,
+                    changeDescription.SessionId,
                     changeDescription.Reason.ToString()
                 );
-                
+
                 service.OnSessionChange(changeDescription);
             }
         }
@@ -106,15 +91,15 @@ protected override bool OnPowerEvent(PowerBroadcastStatus powerStatus)
             if (_hostedServices == null)
             {
                 Logger.LogDebug("No hosted services, returning");
-                
+
                 return true;
             }
 
             // Forward the event to all registered I(PowerEventAware)HostedServices.
             foreach (var service in _hostedServices)
             {
                 Logger.LogDebug("Notifying service {service} about power event: {powerStatus}", service.GetType().FullName, powerStatus);
-                
+
                 service.OnPowerEvent(powerStatus);
             }
 
@@ -123,4 +108,3 @@ protected override bool OnPowerEvent(PowerBroadcastStatus powerStatus)
         }
     }
 }
-#pragma warning restore CA1416 // Validate platform compatibility - constructor handles that

src/CodeCaster.WindowsServiceExtensions/Lifetime/HostApplicationStartupLifetime.cs

@@ -71,6 +71,19 @@ public HostApplicationStartupLifetime(IServiceProvider serviceProvider, IHostEnv
             }
         }
 
+        /// <summary>
+        /// Do not call ServiceBase.Stop() on error.
+        /// </summary>
+        public new Task StopAsync(CancellationToken cancellationToken)
+        {
+            if (!OperatingSystem.IsWindows() || !WindowsServiceHelpers.IsWindowsService() || ExitCode == 0)
+            {
+                base.StopAsync(cancellationToken);
+            }
+            
+            return Task.CompletedTask;
+        }
+
         /// <summary>
         /// Override to execute startup code, no need to call base. Async because who knows.
         /// </summary>

src/CodeCaster.WindowsServiceExtensions/Service/WindowsServiceBackgroundService.cs

@@ -65,7 +65,7 @@ protected sealed override async Task ExecuteAsync(CancellationToken stoppingToke
             }
             catch (Exception)
             {
-                Logger.LogDebug("Setting process exit code to {exitCode}", ErrorInvalidData);
+                Logger.LogInformation("Exception occurred, setting process exit code to {exitCode}", ErrorInvalidData);
 
                 // The .NET host will shut down with code 0 if we don't do this.
                 Environment.ExitCode = ErrorInvalidData;
@@ -76,11 +76,12 @@ protected sealed override async Task ExecuteAsync(CancellationToken stoppingToke
                     Logger.LogDebug("Setting service exit code to {exitCode}", ErrorInvalidData);
 
                     // To report to the Service Control Manager on failure, is uint so > 0.
-                    ServiceLifetime.ExitCode = ErrorInvalidData;
+                    ServiceLifetime.ExitCode = ErrorInvalidData + 1;
                 }
 #pragma warning restore CA1416 // Validate platform compatibility
 
-                // Let the BackgroundService handle the exception.
+                // Let the BackgroundService handle and log the exception.
+                // Do _not_ call ServiceBase.Stop(), or it'll think we exited successfully.
                 throw;
             }
         }

test/TestServiceThatThrows/Program.cs

@@ -12,6 +12,9 @@ namespace TestServiceThatThrows
 {
     public static class Program
     {
+        // Fake doing at least a second's work to not throw immediately...
+        public static int SecondsToWaitBeforeThrowing;
+
         public static async Task Main()
         {
             // Hint: Reattach to Process (Shift+Alt+P)
@@ -22,6 +25,8 @@ public static async Task Main()
                 Debugger.Break();
             }
 
+            SecondsToWaitBeforeThrowing = Debugger.IsAttached ? 1 : 31;
+
             await new HostBuilder()
                 .ConfigureLogging(l => l.AddConsole())
                 .ConfigureServices((s) =>
@@ -45,7 +50,7 @@ public static async Task Main()
                     // Should give startup error.
                     //throw new InvalidOperationException("Heh");
                 })
-                .UseWindowsService()
+                //.UseWindowsService()
                 .UseWindowsServiceExtensions()
                 //.UseWindowsServiceExtensions(o => 
                 //{
@@ -83,7 +88,7 @@ public class MyFaultyService : IHostedService
     {
         public async Task StartAsync(CancellationToken cancellationToken)
         {
-            await Task.Delay(5000, cancellationToken);
+            await Task.Delay(Program.SecondsToWaitBeforeThrowing * 1000, cancellationToken);
 
             // This works, kills the host (awaits startup).
             throw new InvalidOperationException("This service is not supposed to start");
@@ -107,7 +112,7 @@ public MyFaultyBackgroundService(ILogger<MyFaultyBackgroundService> logger)
         protected override async Task ExecuteAsync(CancellationToken stoppingToken)
         {
             // Fake doing at least some work...
-            await Task.Delay(500, stoppingToken);
+            await Task.Delay(Program.SecondsToWaitBeforeThrowing * 1000, stoppingToken);
 
             _logger.LogError("This service is not supposed to start, but this error won't kill the host");
 
@@ -130,10 +135,7 @@ protected override async Task TryExecuteAsync(CancellationToken stoppingToken)
         {
             Logger.LogInformation("Sleeping, then throwing");
 
-            // Fake doing at least a second's work to not throw immediately...
-            int secondsToWait = Debugger.IsAttached ? 1 : 31;
-
-            await Task.Delay(secondsToWait * 1000, stoppingToken);
+            await Task.Delay(Program.SecondsToWaitBeforeThrowing * 1000, stoppingToken);
 
             // This will now stop the host application.
             throw new InvalidOperationException("This service is not supposed to start");