Clean up

Author: JamesNK

src/Hosting/Hosting/src/Internal/HostingApplicationDiagnostics.cs

@@ -390,7 +390,7 @@ private void RecordRequestStartMetrics(HttpContext httpContext)
         hasDiagnosticListener = false;
 
         var headers = httpContext.Request.Headers;
-        var activity = ActivityCreator.CreateActivity(
+        var activity = ActivityCreator.CreateFromRemoteActivity(
             _activitySource,
             _propagator,
             headers,

src/Shared/Diagnostics/ActivityCreator.cs

@@ -10,26 +10,21 @@ internal static class ActivityCreator
     /// <summary>
     /// Create an activity with details received from a remote source.
     /// </summary>
-    public static Activity? CreateActivity(
+    public static Activity? CreateFromRemoteActivity(
         ActivitySource activitySource,
         DistributedContextPropagator propagator,
-        object? distributedContextCarrier,
+        object distributedContextCarrier,
         DistributedContextPropagator.PropagatorGetterCallback propagatorGetter,
         string activityName,
         IEnumerable<KeyValuePair<string, object?>>? tags,
         IEnumerable<ActivityLink>? links,
         bool diagnosticsOrLoggingEnabled)
     {
-        string? requestId = null;
-        string? traceState = null;
-        if (distributedContextCarrier != null)
-        {
-            propagator.ExtractTraceIdAndState(
-                distributedContextCarrier,
-                propagatorGetter,
-                out requestId,
-                out traceState);
-        }
+        propagator.ExtractTraceIdAndState(
+            distributedContextCarrier,
+            propagatorGetter,
+            out var requestId,
+            out var traceState);
 
         Activity? activity = null;
         if (activitySource.HasListeners())
@@ -93,19 +88,16 @@ internal static class ActivityCreator
 
         // Baggage can be used regardless of whether a distributed trace id was present on the inbound request.
         // https://www.w3.org/TR/baggage/#abstract
-        if (distributedContextCarrier != null)
-        {
-            var baggage = propagator.ExtractBaggage(distributedContextCarrier, propagatorGetter);
+        var baggage = propagator.ExtractBaggage(distributedContextCarrier, propagatorGetter);
 
-            // AddBaggage adds items at the beginning  of the list, so we need to add them in reverse to keep the same order as the client
-            // By contract, the propagator has already reversed the order of items so we need not reverse it again
-            // Order could be important if baggage has two items with the same key (that is allowed by the contract)
-            if (baggage is not null)
+        // AddBaggage adds items at the beginning  of the list, so we need to add them in reverse to keep the same order as the client
+        // By contract, the propagator has already reversed the order of items so we need not reverse it again
+        // Order could be important if baggage has two items with the same key (that is allowed by the contract)
+        if (baggage is not null)
+        {
+            foreach (var baggageItem in baggage)
             {
-                foreach (var baggageItem in baggage)
-                {
-                    activity.AddBaggage(baggageItem.Key, baggageItem.Value);
-                }
+                activity.AddBaggage(baggageItem.Key, baggageItem.Value);
             }
         }
 

src/SignalR/server/Core/src/Internal/DefaultHubDispatcher.cs

@@ -848,33 +848,40 @@ public override IReadOnlyList<Type> GetParameterTypes(string methodName)
         IEnumerable<KeyValuePair<string, object?>> tags =
         [
             new("rpc.method", methodName),
-                new("rpc.system", "signalr"),
-                new("rpc.service", _fullHubName),
-                // See https://github.com/dotnet/aspnetcore/blob/027c60168383421750f01e427e4f749d0684bc02/src/Servers/Kestrel/Core/src/Internal/Infrastructure/KestrelMetrics.cs#L308
-                // And https://github.com/dotnet/aspnetcore/issues/43786
-                //new("server.address", ...),
-            ];
+            new("rpc.system", "signalr"),
+            new("rpc.service", _fullHubName),
+            // See https://github.com/dotnet/aspnetcore/blob/027c60168383421750f01e427e4f749d0684bc02/src/Servers/Kestrel/Core/src/Internal/Infrastructure/KestrelMetrics.cs#L308
+            // And https://github.com/dotnet/aspnetcore/issues/43786
+            //new("server.address", ...),
+        ];
         IEnumerable<ActivityLink>? links = (linkedActivity is not null) ? [new ActivityLink(linkedActivity.Context)] : null;
 
-        var propagator = serviceProvider.GetService<DistributedContextPropagator>() ?? DistributedContextPropagator.Current;        
+        var propagator = serviceProvider.GetService<DistributedContextPropagator>() ?? DistributedContextPropagator.Current;
 
-        var activity = ActivityCreator.CreateActivity(
-            activitySource,
-            propagator,
-            headers,
-            static (object? carrier, string fieldName, out string? fieldValue, out IEnumerable<string>? fieldValues) =>
-            {
-                fieldValues = default;
-                var headers = (IDictionary<string, string>)carrier!;
-                headers.TryGetValue(fieldName, out fieldValue);
-            },
-            name,
-            tags,
-            links,
-            loggingEnabled);
-
-        Debug.Assert(activity != null, "Activity should always be created.");
-        activity.Start();
+        Activity? activity;
+        if (headers != null)
+        {
+            activity = ActivityCreator.CreateFromRemoteActivity(
+                activitySource,
+                propagator,
+                headers,
+                static (object? carrier, string fieldName, out string? fieldValue, out IEnumerable<string>? fieldValues) =>
+                {
+                    fieldValues = default;
+                    var headers = (IDictionary<string, string>)carrier!;
+                    headers.TryGetValue(fieldName, out fieldValue);
+                },
+                name,
+                tags,
+                links,
+                loggingEnabled);
+        }
+        else
+        {
+            activity = activitySource.CreateActivity(name, ActivityKind.Server, parentId: null, tags: tags, links: links);
+        }
+
+        activity?.Start();
 
         return activity;
     }