shutdown is a request, not a notification

Author: david-driscoll

src/Protocol/General/IShutdownHandler.cs

@@ -11,5 +11,5 @@ public static partial class GeneralNames
     }
 
     [Serial, Method(Shutdown)]
-    public interface IShutdownHandler : INotificationHandler { }
+    public interface IShutdownHandler : IRequestHandler<object> { }
 }

src/Server/Handlers/ShutdownHandler.cs

@@ -1,3 +1,4 @@
+using System.Threading;
 using System.Threading.Tasks;
 using OmniSharp.Extensions.LanguageServer.Protocol;
 using OmniSharp.Extensions.LanguageServer.Server.Abstractions;
@@ -6,19 +7,18 @@ namespace OmniSharp.Extensions.LanguageServer.Server.Handlers
 {
     public class ShutdownHandler : IShutdownHandler, IAwaitableTermination
     {
-        public Task Handle()
+        public event ShutdownEventHandler Shutdown;
+
+        public bool ShutdownRequested { get; private set; }
+
+        private readonly TaskCompletionSource<bool> _shutdownSource = new TaskCompletionSource<bool>(TaskContinuationOptions.LongRunning);
+        Task IAwaitableTermination.WasShutDown => _shutdownSource.Task;
+        public Task Handle(object request, CancellationToken token)
         {
             ShutdownRequested = true;
             Shutdown?.Invoke(ShutdownRequested);
-            shutdownSource.SetResult(true); // after all event sinks were notified
+            _shutdownSource.SetResult(true); // after all event sinks were notified
             return Task.CompletedTask;
         }
-
-        public event ShutdownEventHandler Shutdown;
-
-        public bool ShutdownRequested { get; private set; }
-
-        private readonly TaskCompletionSource<bool> shutdownSource = new TaskCompletionSource<bool>(TaskContinuationOptions.LongRunning);
-        Task IAwaitableTermination.WasShutDown => shutdownSource.Task;
     }
 }