OmniSharp · JoeRobich · Jun 29, 2026 · Jun 26, 2026 · Jun 26, 2026 · Jun 29, 2026
diff --git a/Directory.Packages.props b/Directory.Packages.props
@@ -1,6 +1,8 @@
 <?xml version="1.0" encoding="utf-8" ?>
 <Project>
   <PropertyGroup>
+    <LibraryTargetFrameworks>netstandard2.1;netstandard2.0;net8.0;net10.0</LibraryTargetFrameworks>
+    <TestTargetFrameworks>net10.0</TestTargetFrameworks>
     <CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GeneratedFiles</CompilerGeneratedFilesOutputPath>
   </PropertyGroup>
   <ItemGroup>

diff --git a/architecture.md b/architecture.md
diff --git a/src/Client/Client.csproj b/src/Client/Client.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFrameworks>netstandard2.1;netstandard2.0;net6.0;net8.0</TargetFrameworks>
+        <TargetFrameworks>$(LibraryTargetFrameworks)</TargetFrameworks>
         <PlatformTarget>AnyCPU</PlatformTarget>
         <AssemblyName>OmniSharp.Extensions.LanguageClient</AssemblyName>
         <RootNamespace>OmniSharp.Extensions.LanguageServer.Client</RootNamespace>

diff --git a/src/Client/LanguageClient.cs b/src/Client/LanguageClient.cs
@@ -446,7 +446,7 @@ private Supports<T> UseOrTryAndFindCapability<T>(Supports<T> supports) where T :
 
         public IObservable<InitializeResult> Start => _initializeComplete.AsObservable();
 
-        bool IResponseRouter.TryGetRequest(long id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask)
+        bool IResponseRouter.TryGetRequest(object id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask)
         {
             return _responseRouter.TryGetRequest(id, out method, out pendingTask);
         }

diff --git a/src/Dap.Client/Dap.Client.csproj b/src/Dap.Client/Dap.Client.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFrameworks>netstandard2.1;netstandard2.0;net6.0;net8.0</TargetFrameworks>
+        <TargetFrameworks>$(LibraryTargetFrameworks)</TargetFrameworks>
         <PlatformTarget>AnyCPU</PlatformTarget>
         <AssemblyName>OmniSharp.Extensions.DebugAdapter.Client</AssemblyName>
         <RootNamespace>OmniSharp.Extensions.DebugAdapter.Client</RootNamespace>

diff --git a/src/Dap.Protocol.Proposals/Dap.Protocol.Proposals.csproj b/src/Dap.Protocol.Proposals/Dap.Protocol.Proposals.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFrameworks>netstandard2.1;netstandard2.0;net6.0;net8.0</TargetFrameworks>
+        <TargetFrameworks>$(LibraryTargetFrameworks)</TargetFrameworks>
         <PlatformTarget>AnyCPU</PlatformTarget>
         <AssemblyName>OmniSharp.Extensions.DebugAdapter.Proposals</AssemblyName>
         <RootNamespace>OmniSharp.Extensions.DebugAdapter.Protocol</RootNamespace>

diff --git a/src/Dap.Protocol/Dap.Protocol.csproj b/src/Dap.Protocol/Dap.Protocol.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFrameworks>netstandard2.1;netstandard2.0;net6.0;net8.0</TargetFrameworks>
+        <TargetFrameworks>$(LibraryTargetFrameworks)</TargetFrameworks>
         <PlatformTarget>AnyCPU</PlatformTarget>
         <AssemblyName>OmniSharp.Extensions.DebugAdapter</AssemblyName>
         <RootNamespace>OmniSharp.Extensions.DebugAdapter.Protocol</RootNamespace>

diff --git a/src/Dap.Protocol/IDebugAdapterProtocolProxy.cs b/src/Dap.Protocol/IDebugAdapterProtocolProxy.cs
@@ -59,7 +59,7 @@ public Task<TResponse> SendRequest<TResponse>(IRequest<TResponse> request, Cance
             return _responseRouter.SendRequest(request, cancellationToken);
         }
 
-        bool IResponseRouter.TryGetRequest(long id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask)
+        bool IResponseRouter.TryGetRequest(object id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask)
         {
             return _responseRouter.TryGetRequest(id, out method, out pendingTask);
         }

diff --git a/src/Dap.Server/Dap.Server.csproj b/src/Dap.Server/Dap.Server.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFrameworks>netstandard2.1;netstandard2.0;net6.0;net8.0</TargetFrameworks>
+        <TargetFrameworks>$(LibraryTargetFrameworks)</TargetFrameworks>
         <PlatformTarget>AnyCPU</PlatformTarget>
         <AssemblyName>OmniSharp.Extensions.DebugAdapter.Server</AssemblyName>
         <RootNamespace>OmniSharp.Extensions.DebugAdapter.Server</RootNamespace>

diff --git a/src/Dap.Shared/Dap.Shared.csproj b/src/Dap.Shared/Dap.Shared.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFrameworks>netstandard2.1;netstandard2.0;net6.0;net8.0</TargetFrameworks>
+        <TargetFrameworks>$(LibraryTargetFrameworks)</TargetFrameworks>
         <PlatformTarget>AnyCPU</PlatformTarget>
         <AssemblyName>OmniSharp.Extensions.DebugAdapter.Shared</AssemblyName>
         <RootNamespace>OmniSharp.Extensions.DebugAdapter.Shared</RootNamespace>

diff --git a/src/Dap.Shared/DapResponseRouter.cs b/src/Dap.Shared/DapResponseRouter.cs
@@ -16,8 +16,8 @@ public class DapResponseRouter : IResponseRouter
         internal readonly IOutputHandler OutputHandler;
         internal readonly ISerializer Serializer;
 
-        internal readonly ConcurrentDictionary<long, (string method, TaskCompletionSource<JToken> pendingTask)> Requests =
-            new ConcurrentDictionary<long, (string method, TaskCompletionSource<JToken> pendingTask)>();
+        internal readonly ConcurrentDictionary<object, (string method, TaskCompletionSource<JToken> pendingTask)> Requests =
+            new ConcurrentDictionary<object, (string method, TaskCompletionSource<JToken> pendingTask)>();
 
         internal static readonly ConcurrentDictionary<Type, string> MethodCache =
             new ConcurrentDictionary<Type, string>();
@@ -69,7 +69,7 @@ public IResponseRouterReturns SendRequest<T>(string method, T @params)
             return new ResponseRouterReturnsImpl(this, method, @params);
         }
 
-        public bool TryGetRequest(long id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask)
+        public bool TryGetRequest(object id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask)
         {
             var result = Requests.TryGetValue(id, out var source);
             method = source.method;

diff --git a/src/Dap.Testing/Dap.Testing.csproj b/src/Dap.Testing/Dap.Testing.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFrameworks>netstandard2.1;netstandard2.0;net6.0;net8.0</TargetFrameworks>
+        <TargetFrameworks>$(LibraryTargetFrameworks)</TargetFrameworks>
         <PlatformTarget>AnyCPU</PlatformTarget>
         <AssemblyName>OmniSharp.Extensions.DebugAdapter.Testing</AssemblyName>
         <RootNamespace>OmniSharp.Extensions.DebugAdapter.Testing</RootNamespace>

diff --git a/src/JsonRpc.Testing/JsonRpc.Testing.csproj b/src/JsonRpc.Testing/JsonRpc.Testing.csproj
@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
     <PropertyGroup>
-        <TargetFrameworks>netstandard2.1;netstandard2.0;net6.0;net8.0</TargetFrameworks>
+        <TargetFrameworks>$(LibraryTargetFrameworks)</TargetFrameworks>
         <PlatformTarget>AnyCPU</PlatformTarget>
         <AssemblyName>OmniSharp.Extensions.JsonRpc.Testing</AssemblyName>
         <RootNamespace>OmniSharp.Extensions.JsonRpc.Testing</RootNamespace>

diff --git a/src/JsonRpc/DefaultJsonRpcServerFacade.cs b/src/JsonRpc/DefaultJsonRpcServerFacade.cs
@@ -50,7 +50,7 @@ public Task<TResponse> SendRequest<TResponse>(IRequest<TResponse> request, Cance
             return _responseRouter.SendRequest(request, cancellationToken);
         }
 
-        bool IResponseRouter.TryGetRequest(long id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask)
+        bool IResponseRouter.TryGetRequest(object id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask)
         {
             return _responseRouter.TryGetRequest(id, out method, out pendingTask);
         }

diff --git a/src/JsonRpc/IResponseRouter.cs b/src/JsonRpc/IResponseRouter.cs
@@ -14,6 +14,6 @@ public interface IResponseRouter
         IResponseRouterReturns SendRequest<T>(string method, T @params);
         IResponseRouterReturns SendRequest(string method);
         Task<TResponse> SendRequest<TResponse>(IRequest<TResponse> request, CancellationToken cancellationToken);
-        bool TryGetRequest(long id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask);
+        bool TryGetRequest(object id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask);
     }
 }
diff --git a/src/JsonRpc/InputHandler.cs b/src/JsonRpc/InputHandler.cs
@@ -323,6 +323,7 @@ internal async Task ProcessInputStream(CancellationToken cancellationToken)
             try
             {
                 var headersParsed = false;
+                var invalidContentType = false;
                 long length = 0;
                 do
                 {
@@ -337,6 +338,7 @@ internal async Task ProcessInputStream(CancellationToken cancellationToken)
                         {
                             if (TryParseHeaders(ref buffer, out var line))
                             {
+                                invalidContentType = !IsSupportedContentType(line);
                                 if (TryParseContentLength(ref line, out length))
                                 {
                                     headersParsed = true;
@@ -346,7 +348,16 @@ internal async Task ProcessInputStream(CancellationToken cancellationToken)
 
                         if (headersParsed && length == 0)
                         {
-                            HandleRequest(new ReadOnlySequence<byte>(Array.Empty<byte>()));
+                            if (invalidContentType)
+                            {
+                                _outputHandler.Send(new ParseError(string.Empty));
+                                invalidContentType = false;
+                            }
+                            else
+                            {
+                                HandleRequest(new ReadOnlySequence<byte>(Array.Empty<byte>()));
+                            }
+
                             headersParsed = false;
                         }
 
@@ -356,7 +367,16 @@ internal async Task ProcessInputStream(CancellationToken cancellationToken)
                             {
                                 headersParsed = false;
                                 length = 0;
-                                HandleRequest(line);
+                                if (invalidContentType)
+                                {
+                                    _outputHandler.Send(new ParseError(string.Empty));
+                                    invalidContentType = false;
+                                }
+                                else
+                                {
+                                    HandleRequest(line);
+                                }
+
                                 dataParsed = true;
                             }
                         }
@@ -384,6 +404,41 @@ internal async Task ProcessInputStream(CancellationToken cancellationToken)
             }
         }
 
+        private static bool IsSupportedContentType(ReadOnlySequence<byte> headers)
+        {
+            var headerText = Encoding.ASCII.GetString(headers.ToArray());
+            foreach (var header in headerText.Split(new[] { "\r\n" }, StringSplitOptions.RemoveEmptyEntries))
+            {
+                var colonIndex = header.IndexOf(':');
+                if (colonIndex < 0)
+                {
+                    continue;
+                }
+
+                var name = header.Substring(0, colonIndex).Trim();
+                if (!string.Equals(name, "Content-Type", StringComparison.OrdinalIgnoreCase))
+                {
+                    continue;
+                }
+
+                var value = header.Substring(colonIndex + 1);
+                foreach (var part in value.Split(';').Skip(1))
+                {
+                    var pair = part.Split(new[] { '=' }, 2);
+                    if (pair.Length != 2 || !string.Equals(pair[0].Trim(), "charset", StringComparison.OrdinalIgnoreCase))
+                    {
+                        continue;
+                    }
+
+                    var charset = pair[1].Trim().Trim('"');
+                    return string.Equals(charset, "utf-8", StringComparison.OrdinalIgnoreCase) ||
+                           string.Equals(charset, "utf8", StringComparison.OrdinalIgnoreCase);
+                }
+            }
+
+            return true;
+        }
+
         private void HandleRequest(in ReadOnlySequence<byte> request)
         {
             JToken payload;
@@ -407,51 +462,46 @@ private void HandleRequest(in ReadOnlySequence<byte> request)
 
             // using (_logger.TimeDebug("InputHandler is handling the request"))
             // {
-            var (requests, hasResponse) = _receiver.GetRequests(payload);
-            if (hasResponse)
+            var (requests, _) = _receiver.GetRequests(payload);
+            var items = requests as Renor[] ?? requests.ToArray();
+            foreach (var response in items.Where(x => x.IsResponse).Select(x => x.Response!))
             {
-                foreach (var response in requests.Where(x => x.IsResponse).Select(x => x.Response!))
+                // _logger.LogDebug("Handling Response for request {ResponseId}", response.Id);
+                if (response.Id is null)
                 {
-                    // _logger.LogDebug("Handling Response for request {ResponseId}", response.Id);
-                    var id = response.Id is string s ? long.Parse(s) : response.Id is long l ? l : -1;
-                    if (id < 0)
-                    {
-                        // _logger.LogDebug("Id was out of range, skipping request {ResponseId}", response.Id);
-                        continue;
-                    }
+                    continue;
+                }
 
-                    if (!_responseRouter.TryGetRequest(id, out var method, out var tcs))
-                    {
-                        // _logger.LogDebug("Request {ResponseId} was not found in the response router, unable to complete", response.Id);
-                        continue;
-                    }
+                if (!_responseRouter.TryGetRequest(response.Id, out var method, out var tcs) &&
+                    !(response.Id is string s && long.TryParse(s, out var numericId) && _responseRouter.TryGetRequest(numericId, out method, out tcs)))
+                {
+                    // _logger.LogDebug("Request {ResponseId} was not found in the response router, unable to complete", response.Id);
+                    continue;
+                }
 
-                    _inputQueue.OnNext(
-                        Observable.Create<Unit>(
-                            observer =>
+                _inputQueue.OnNext(
+                    Observable.Create<Unit>(
+                        observer =>
+                        {
+                            if (response is ServerResponse serverResponse)
                             {
-                                if (response is ServerResponse serverResponse)
-                                {
-                                    // _logger.LogDebug("Setting successful Response for {ResponseId}", response.Id);
-                                    tcs.TrySetResult(serverResponse.Result);
-                                }
-                                else if (response is ServerError serverError)
-                                {
-                                    // _logger.LogDebug("Setting error for {ResponseId}", response.Id);
-                                    tcs.TrySetException(DefaultErrorParser(method, serverError, _getException));
-                                }
-
-                                observer.OnCompleted();
-                                return Disposable.Empty;
+                                // _logger.LogDebug("Setting successful Response for {ResponseId}", response.Id);
+                                tcs.TrySetResult(serverResponse.Result);
+                            }
+                            else if (response is ServerError serverError)
+                            {
+                                // _logger.LogDebug("Setting error for {ResponseId}", response.Id);
+                                tcs.TrySetException(DefaultErrorParser(method, serverError, _getException));
                             }
-                        )
-                    );
-                }
 
-                return;
+                            observer.OnCompleted();
+                            return Disposable.Empty;
+                        }
+                    )
+                );
             }
 
-            foreach (var item in requests)
+            foreach (var item in items)
             {
                 if (item.IsRequest && item.Request != null)
                 {
@@ -463,7 +513,7 @@ private void HandleRequest(in ReadOnlySequence<byte> request)
                         {
                             _logger.LogDebug("Request handler was not found (or not setup) {Method} {ResponseId}", item.Request.Method, item.Request.Id);
                             _outputHandler.Send(new MethodNotFound(item.Request.Id, item.Request.Method));
-                            return;
+                            continue;
                         }
 
                         var requestHandle = _requestInvoker.InvokeRequest(descriptor, item.Request);
@@ -514,7 +564,7 @@ private void HandleRequest(in ReadOnlySequence<byte> request)
                             _logger.LogDebug("Notification handler was not found (or not setup) {Method}", item.Notification.Method);
                             // TODO: Figure out a good way to send this feedback back.
                             // _outputHandler.Send(new RpcError(null, new ErrorMessage(-32601, $"Method not found - {item.Notification.Method}")));
-                            return;
+                            continue;
                         }
 
                         _requestInvoker.InvokeNotification(descriptor, item.Notification);
@@ -548,6 +598,8 @@ private static Exception DefaultErrorParser(string? method, ServerError error, C
                 ErrorCodes.ParseError           => new ParseErrorException(error.Id),
                 ErrorCodes.RequestCancelled     => new RequestCancelledException(error.Id),
                 ErrorCodes.ContentModified      => new ContentModifiedException(error.Id),
+                ErrorCodes.ServerCancelled      => new ServerCancelledException(error.Id),
+                ErrorCodes.RequestFailed        => new RequestFailedException(error.Id),
                 ErrorCodes.UnknownErrorCode     => new UnknownErrorException(error.Id),
                 ErrorCodes.Exception            => new JsonRpcException(ErrorCodes.Exception, error.Id, error.Error.Message, error.Error.Data?.ToString()),
                 _ => customHandler?.Invoke(error, method ?? "UNKNOWN") ??

diff --git a/src/JsonRpc/JsonRpc.csproj b/src/JsonRpc/JsonRpc.csproj
@@ -1,6 +1,6 @@
 <Project Sdk="Microsoft.NET.Sdk">
     <PropertyGroup>
-        <TargetFrameworks>netstandard2.1;netstandard2.0;net6.0;net8.0</TargetFrameworks>
+        <TargetFrameworks>$(LibraryTargetFrameworks)</TargetFrameworks>
         <PlatformTarget>AnyCPU</PlatformTarget>
         <AssemblyName>OmniSharp.Extensions.JsonRpc</AssemblyName>
         <RootNamespace>OmniSharp.Extensions.JsonRpc</RootNamespace>

diff --git a/src/JsonRpc/JsonRpcServerBase.cs b/src/JsonRpc/JsonRpcServerBase.cs
@@ -47,7 +47,7 @@ public IResponseRouterReturns SendRequest(string method)
             return ResponseRouter.SendRequest(method);
         }
 
-        bool IResponseRouter.TryGetRequest(long id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask)
+        bool IResponseRouter.TryGetRequest(object id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask)
         {
             return ResponseRouter.TryGetRequest(id, out method, out pendingTask);
         }

diff --git a/src/JsonRpc/NoopResponseRouter.cs b/src/JsonRpc/NoopResponseRouter.cs
@@ -44,7 +44,7 @@ public Task<TResponse> SendRequest<TResponse>(IRequest<TResponse> request, Cance
             return Task.FromResult<TResponse>(default!);
         }
 
-        bool IResponseRouter.TryGetRequest(long id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask)
+        bool IResponseRouter.TryGetRequest(object id, [NotNullWhen(true)] out string? method, [NotNullWhen(true)] out TaskCompletionSource<JToken>? pendingTask)
         {
             method = default!;
             pendingTask = default!;