Run Can_UseIHttpContextAccessor_InTool in stateless mode

Author: halter73

src/ModelContextProtocol.AspNetCore/HttpMcpSession.cs

@@ -7,7 +7,7 @@ namespace ModelContextProtocol.AspNetCore;
 internal sealed class HttpMcpSession<TTransport>(
     string sessionId,
     TTransport transport,
-    (string Type, string Value, string Issuer)? userIdClaim,
+    StatelessUserId? userId,
     TimeProvider timeProvider) : IAsyncDisposable
     where TTransport : ITransport
 {
@@ -17,7 +17,7 @@ internal sealed class HttpMcpSession<TTransport>(
 
     public string Id { get; } = sessionId;
     public TTransport Transport { get; } = transport;
-    public (string Type, string Value, string Issuer)? UserIdClaim { get; } = userIdClaim;
+    public StatelessUserId? UserIdClaim { get; } = userId;
 
     public CancellationToken SessionClosed => _disposeCts.Token;
 

src/ModelContextProtocol.AspNetCore/StatelessSessionId.cs

@@ -9,5 +9,5 @@ internal sealed class StatelessSessionId
     public Implementation? ClientInfo { get; init; }
 
     [JsonPropertyName("userIdClaim")]
-    public (string Type, string Value, string Issuer)? UserIdClaim { get; init; }
+    public StatelessUserId? UserIdClaim { get; init; }
 }

src/ModelContextProtocol.AspNetCore/StatelessUserId.cs

@@ -0,0 +1,3 @@
+namespace ModelContextProtocol.AspNetCore;
+
+internal sealed record StatelessUserId(string Type, string value, string Issuer);

src/ModelContextProtocol.AspNetCore/StreamableHttpHandler.cs

@@ -314,7 +314,7 @@ internal static Task RunSessionAsync(HttpContext httpContext, IMcpServer session
     // SignalR only checks for ClaimTypes.NameIdentifier in HttpConnectionDispatcher, but AspNetCore.Antiforgery checks that plus the sub and UPN claims.
     // However, we short-circuit unlike antiforgery since we expect to call this to verify MCP messages a lot more frequently than
     // verifying antiforgery tokens from <form> posts.
-    internal static (string Type, string Value, string Issuer)? GetUserIdClaim(ClaimsPrincipal user)
+    internal static StatelessUserId? GetUserIdClaim(ClaimsPrincipal user)
     {
         if (user?.Identity?.IsAuthenticated != true)
         {
@@ -325,7 +325,7 @@ internal static (string Type, string Value, string Issuer)? GetUserIdClaim(Claim
 
         if (claim is { } idClaim)
         {
-            return (idClaim.Type, idClaim.Value, idClaim.Issuer);
+            return new(idClaim.Type, idClaim.Value, idClaim.Issuer);
         }
 
         return null;

tests/ModelContextProtocol.AspNetCore.Tests/MapMcpTests.cs

@@ -46,10 +46,13 @@ public async Task MapMcp_ThrowsInvalidOperationException_IfWithHttpTransportIsNo
     [Fact]
     public async Task Can_UseIHttpContextAccessor_InTool()
     {
-        Assert.SkipWhen(UseStreamableHttp, "IHttpContextAccessor is not currently supported with Streamable HTTP." +
-            "TODO: Support it in stateless mode by manually capturing and flowing execution context.");
+        Assert.SkipWhen(UseStreamableHttp && !Stateless,
+            """
+            IHttpContextAccessor is not currently supported with non-stateless Streamable HTTP.
+            TODO: Support it in stateless mode by manually capturing and flowing execution context.
+            """);
 
-        Builder.Services.AddMcpServer().WithHttpTransport().WithTools<EchoHttpContextUserTools>();
+        Builder.Services.AddMcpServer().WithHttpTransport(ConfigureStateless).WithTools<EchoHttpContextUserTools>();
 
         Builder.Services.AddHttpContextAccessor();