Address review feedback: move GetUtf8String to EncodingUtilities, remove NoBomUtf8Encoding from StreamClientSessionTransport

Co-authored-by: ericstj <8918108+ericstj@users.noreply.github.com>

Author: Copilot

src/Common/EncodingUtilities.cs

@@ -20,6 +20,19 @@ public static byte[] GetUtf8Bytes(ReadOnlySpan<char> utf16)
         return bytes;
     }
 
+    /// <summary>Decodes a UTF-8 <see cref="ReadOnlySequence{T}"/> to a <see cref="string"/>.</summary>
+    public static string GetUtf8String(in ReadOnlySequence<byte> sequence)
+    {
+        if (sequence.IsEmpty)
+        {
+            return string.Empty;
+        }
+
+        return sequence.IsSingleSegment
+            ? Encoding.UTF8.GetString(sequence.First.Span)
+            : Encoding.UTF8.GetString(sequence.ToArray());
+    }
+
     /// <summary>
     /// Encodes binary data to base64-encoded UTF-8 bytes.
     /// </summary>

src/ModelContextProtocol.Core/Client/StdioClientTransport.cs

@@ -31,6 +31,8 @@ public sealed partial class StdioClientTransport : IClientTransport
     private static readonly object s_consoleEncodingLock = new();
 #endif
 
+    private static readonly UTF8Encoding s_noBomUtf8Encoding = new(encoderShouldEmitUTF8Identifier: false);
+
     private readonly StdioClientTransportOptions _options;
     private readonly ILoggerFactory? _loggerFactory;
 
@@ -85,10 +87,10 @@ public async Task<ITransport> ConnectAsync(CancellationToken cancellationToken =
                 UseShellExecute = false,
                 CreateNoWindow = true,
                 WorkingDirectory = _options.WorkingDirectory ?? Environment.CurrentDirectory,
-                StandardOutputEncoding = StreamClientSessionTransport.NoBomUtf8Encoding,
-                StandardErrorEncoding = StreamClientSessionTransport.NoBomUtf8Encoding,
+                StandardOutputEncoding = s_noBomUtf8Encoding,
+                StandardErrorEncoding = s_noBomUtf8Encoding,
 #if NET
-                StandardInputEncoding = StreamClientSessionTransport.NoBomUtf8Encoding,
+                StandardInputEncoding = s_noBomUtf8Encoding,
 #endif
             };
 
@@ -173,7 +175,7 @@ public async Task<ITransport> ConnectAsync(CancellationToken cancellationToken =
                 Encoding originalInputEncoding = Console.InputEncoding;
                 try
                 {
-                    Console.InputEncoding = StreamClientSessionTransport.NoBomUtf8Encoding;
+                    Console.InputEncoding = s_noBomUtf8Encoding;
                     processStarted = process.Start();
                 }
                 finally

src/ModelContextProtocol.Core/Client/StreamClientSessionTransport.cs

@@ -2,7 +2,6 @@
 using ModelContextProtocol.Protocol;
 using System.Buffers;
 using System.IO.Pipelines;
-using System.Text;
 using System.Text.Json;
 
 namespace ModelContextProtocol.Client;
@@ -12,8 +11,6 @@ internal class StreamClientSessionTransport : TransportBase
 {
     private static readonly byte[] s_newlineBytes = "\n"u8.ToArray();
 
-    internal static UTF8Encoding NoBomUtf8Encoding { get; } = new(encoderShouldEmitUTF8Identifier: false);
-
     private readonly PipeReader _serverOutputPipe;
     private readonly Stream _serverInputStream;
     private readonly SemaphoreSlim _sendLock = new(1, 1);
@@ -120,7 +117,7 @@ private async Task ProcessLineAsync(ReadOnlySequence<byte> line, CancellationTok
     {
         if (Logger.IsEnabled(LogLevel.Trace))
         {
-            LogTransportReceivedMessageSensitive(Name, PipeReaderExtensions.GetUtf8String(line));
+            LogTransportReceivedMessageSensitive(Name, EncodingUtilities.GetUtf8String(line));
         }
 
         try
@@ -144,15 +141,15 @@ private async Task ProcessLineAsync(ReadOnlySequence<byte> line, CancellationTok
             {
                 if (Logger.IsEnabled(LogLevel.Trace))
                 {
-                    LogTransportMessageParseUnexpectedTypeSensitive(Name, PipeReaderExtensions.GetUtf8String(line));
+                    LogTransportMessageParseUnexpectedTypeSensitive(Name, EncodingUtilities.GetUtf8String(line));
                 }
             }
         }
         catch (JsonException ex)
         {
             if (Logger.IsEnabled(LogLevel.Trace))
             {
-                LogTransportMessageParseFailedSensitive(Name, PipeReaderExtensions.GetUtf8String(line), ex);
+                LogTransportMessageParseFailedSensitive(Name, EncodingUtilities.GetUtf8String(line), ex);
             }
             else
             {

src/ModelContextProtocol.Core/Protocol/PipeReaderExtensions.cs

@@ -1,6 +1,5 @@
 using System.Buffers;
 using System.IO.Pipelines;
-using System.Text;
 
 namespace ModelContextProtocol.Protocol;
 
@@ -50,12 +49,6 @@ internal static async Task ReadLinesAsync(
         }
     }
 
-    /// <summary>Decodes a UTF-8 <see cref="ReadOnlySequence{T}"/> to a <see cref="string"/>.</summary>
-    internal static string GetUtf8String(in ReadOnlySequence<byte> sequence) =>
-        sequence.IsSingleSegment
-            ? Encoding.UTF8.GetString(sequence.First.Span)
-            : Encoding.UTF8.GetString(sequence.ToArray());
-
     private static bool EndsWithCarriageReturn(in ReadOnlySequence<byte> sequence)
     {
         if (sequence.IsSingleSegment)

src/ModelContextProtocol.Core/Server/StreamServerTransport.cs

@@ -115,7 +115,7 @@ private async Task ProcessLineAsync(ReadOnlySequence<byte> line, CancellationTok
     {
         if (Logger.IsEnabled(LogLevel.Trace))
         {
-            LogTransportReceivedMessageSensitive(Name, PipeReaderExtensions.GetUtf8String(line));
+            LogTransportReceivedMessageSensitive(Name, EncodingUtilities.GetUtf8String(line));
         }
 
         try
@@ -139,15 +139,15 @@ private async Task ProcessLineAsync(ReadOnlySequence<byte> line, CancellationTok
             {
                 if (Logger.IsEnabled(LogLevel.Trace))
                 {
-                    LogTransportMessageParseUnexpectedTypeSensitive(Name, PipeReaderExtensions.GetUtf8String(line));
+                    LogTransportMessageParseUnexpectedTypeSensitive(Name, EncodingUtilities.GetUtf8String(line));
                 }
             }
         }
         catch (JsonException ex)
         {
             if (Logger.IsEnabled(LogLevel.Trace))
             {
-                LogTransportMessageParseFailedSensitive(Name, PipeReaderExtensions.GetUtf8String(line), ex);
+                LogTransportMessageParseFailedSensitive(Name, EncodingUtilities.GetUtf8String(line), ex);
             }
             else
             {