Draft ActivitySource Child Activity PropagationData solution

src/libraries/System.Diagnostics.DiagnosticSource/src/System.Diagnostics.DiagnosticSource.csproj

@@ -25,13 +25,12 @@
     <Compile Include="System\Diagnostics\DiagnosticSource.cs" />
     <Compile Include="System\Diagnostics\DiagnosticListener.cs" />
     <Compile Include="System\Diagnostics\DiagnosticSourceEventSource.cs" />
-    <Compile Include="$(CommonPath)System\Runtime\CompilerServices\PreserveDependencyAttribute.cs"
-             Link="Common\System\Runtime\CompilerServices\PreserveDependencyAttribute.cs" />
+    <Compile Include="$(CommonPath)System\Runtime\CompilerServices\PreserveDependencyAttribute.cs" Link="Common\System\Runtime\CompilerServices\PreserveDependencyAttribute.cs" />
+    <Compile Include="System\Diagnostics\ParentActivityState.cs" />
     <None Include="DiagnosticSourceUsersGuide.md" />
   </ItemGroup>
   <ItemGroup Condition=" '$(TargetFramework)' != 'netstandard1.1'">
-    <Compile Include="$(CommonPath)System\HexConverter.cs"
-             Link="Common\System\HexConverter.cs" />
+    <Compile Include="$(CommonPath)System\HexConverter.cs" Link="Common\System\HexConverter.cs" />
     <Compile Include="System\Diagnostics\Activity.cs" />
     <Compile Include="System\Diagnostics\ActivityContext.cs" />
     <Compile Include="System\Diagnostics\ActivityCreationOptions.cs" />

src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/ActivityListener.cs

@@ -46,7 +46,7 @@ public ActivityListener()
         /// <summary>
         /// Set or get the callback used to decide allowing creating <see cref="Activity"/> objects with specific data state.
         /// </summary>
-        public GetRequestedData<ActivityContext>? GetRequestedDataUsingContext { get; set; }
+        public GetRequestedData<ParentActivityState>? GetRequestedDataUsingContext { get; set; }
 
         /// <summary>
         /// Dispose will unregister this <see cref="ActivityListener"/> object from listeneing to <see cref="Activity"/> events.

src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/ActivitySource.cs

@@ -133,12 +133,19 @@ public bool HasListeners()
             }
             else
             {
-                ActivityContext initializedContext =  context == default && Activity.Current != null ? Activity.Current.Context : context;
-                listeners.EnumWithFunc(listener => {
+                ParentActivityState parentActivityState = BuildParentActivityState(context);
+                listeners.EnumWithFunc(listener =>
+                {
                     var getRequestedDataUsingContext = listener.GetRequestedDataUsingContext;
                     if (getRequestedDataUsingContext != null)
                     {
-                        ActivityCreationOptions<ActivityContext> aco = new ActivityCreationOptions<ActivityContext>(this, name, initializedContext, kind, tags, links);
+                        ActivityCreationOptions<ParentActivityState> aco = new ActivityCreationOptions<ParentActivityState>(
+                            this,
+                            name,
+                            parentActivityState,
+                            kind,
+                            tags,
+                            links);
                         ActivityDataRequest dr = getRequestedDataUsingContext(ref aco);
                         if (dr > dataRequest)
                         {
@@ -242,6 +249,26 @@ internal void NotifyActivityStop(Activity activity)
                 listeners.EnumWithAction(listener => listener.ActivityStopped?.Invoke(activity));
             }
         }
+
+        private static ParentActivityState BuildParentActivityState(ActivityContext context)
+        {
+            bool isDefaultContext = context == default;
+
+            Activity? currentActivity = Activity.Current;
+            ActivityContext initializedContext = !isDefaultContext
+                ? context
+                : currentActivity?.Context ?? context;
+
+            ActivityDataRequest parentDataRequested = isDefaultContext
+                ? ActivityDataRequest.None
+                : (initializedContext.TraceFlags & ActivityTraceFlags.Recorded) == ActivityTraceFlags.Recorded
+                    ? ActivityDataRequest.AllDataAndRecorded
+                    : currentActivity?.IsAllDataRequested == true
+                        ? ActivityDataRequest.AllData
+                        : ActivityDataRequest.PropagationData;
+
+            return new ParentActivityState(parentDataRequested, initializedContext);
+        }
     }
 
     // SynchronizedList<T> is a helper collection which ensure thread safety on the collection

src/libraries/System.Diagnostics.DiagnosticSource/src/System/Diagnostics/ParentActivityState.cs

@@ -0,0 +1,27 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+namespace System.Diagnostics
+{
+    public readonly struct ParentActivityState : IEquatable<ParentActivityState>
+    {
+        public ParentActivityState(ActivityDataRequest requestedData, ActivityContext activityContext)
+        {
+            RequestedData = requestedData;
+            ActivityContext = activityContext;
+        }
+
+        public ActivityDataRequest RequestedData { get; }
+
+        public ActivityContext ActivityContext { get; }
+
+        public bool Equals(ParentActivityState other) => ActivityContext.Equals(other.ActivityContext) && RequestedData == other.RequestedData;
+
+        public override int GetHashCode() => HashCode.Combine(RequestedData, ActivityContext);
+
+        public override bool Equals(object? obj) => (obj is ParentActivityState context) && Equals(context);
+        public static bool operator ==(ParentActivityState left, ParentActivityState right) => left.Equals(right);
+        public static bool operator !=(ParentActivityState left, ParentActivityState right) => !(left == right);
+    }
+}