Worker instrumentation

src/DotNetWorker.Core/Context/DefaultTraceContext.cs

@@ -1,18 +1,23 @@
-// Copyright (c) .NET Foundation. All rights reserved.
+// Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the MIT License. See License.txt in the project root for license information.
 
+using System.Collections.Generic;
+
 namespace Microsoft.Azure.Functions.Worker
 {
     internal sealed class DefaultTraceContext : TraceContext
     {
-        public DefaultTraceContext(string traceParent, string traceState)
+        public DefaultTraceContext(string traceParent, string traceState, IReadOnlyDictionary<string, string> attributes)
         {
             TraceParent = traceParent;
             TraceState = traceState;
+            Attributes = attributes;
         }
 
         public override string TraceParent { get; }
 
         public override string TraceState { get; }
+
+        public override IReadOnlyDictionary<string, string> Attributes { get; }
     }
 }

src/DotNetWorker.Core/Context/TraceContext.cs

@@ -1,6 +1,8 @@
-// Copyright (c) .NET Foundation. All rights reserved.
+// Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the MIT License. See License.txt in the project root for license information.
 
+using System.Collections.Generic;
+
 namespace Microsoft.Azure.Functions.Worker
 {
     /// <summary>
@@ -17,5 +19,10 @@ public abstract class TraceContext
         /// Gets the state data.
         /// </summary>
         public abstract string TraceState { get; }
+
+        /// <summary>
+        /// Gets the attributes associated with the trace.
+        /// </summary>
+        public abstract IReadOnlyDictionary<string, string> Attributes { get; }
     }
 }

src/DotNetWorker.Core/Diagnostics/OpenTelemetrySchemaVersion.cs

@@ -1,10 +1,11 @@
-// Copyright (c) .NET Foundation. All rights reserved.
+// Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the MIT License. See License.txt in the project root for license information.
 
 namespace Microsoft.Azure.Functions.Worker.Diagnostics
 {
     internal enum OpenTelemetrySchemaVersion
     {
-        v1_17_0
+        V1_17_0,
+        V1_37_0
     }
 }

src/DotNetWorker.Core/Diagnostics/Telemetry/IFunctionTelemetryProvider.cs

@@ -0,0 +1,25 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the MIT License. See License.txt in the project root for license information.
+
+using System.Collections.Generic;
+using System.Diagnostics;
+
+namespace Microsoft.Azure.Functions.Worker.Diagnostics;
+
+/// <summary>
+/// Provides methods for telemetry data collection related to function invocations.
+/// </summary>
+/// <remarks>This interface defines methods to retrieve telemetry attributes and manage the activity lifecycle for
+/// function invocations, enabling detailed monitoring and diagnostics.</remarks>
+internal interface IFunctionTelemetryProvider
+{
+    /// <summary>
+    /// Returns the attributes to be applied to the Activity/Scope for this invocation.
+    /// </summary>
+    IEnumerable<KeyValuePair<string, object>> GetTelemetryAttributes(FunctionContext ctx);
+
+    /// <summary>
+    /// Starts the Activity for this invocation.
+    /// </summary>
+    Activity? StartActivityForInvocation(FunctionContext ctx);
+}

src/DotNetWorker.Core/Diagnostics/Telemetry/TelemetryProviderBase.cs

@@ -0,0 +1,55 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the MIT License. See License.txt in the project root for license information.
+
+using System.Collections.Generic;
+using System.Diagnostics;
+
+namespace Microsoft.Azure.Functions.Worker.Diagnostics;
+
+internal abstract class TelemetryProviderBase : IFunctionTelemetryProvider
+{
+    private static readonly ActivitySource _source
+        = new(TraceConstants.FunctionsActivitySource, TraceConstants.FunctionsActivitySourceVersion);
+
+    protected abstract OpenTelemetrySchemaVersion SchemaVersion { get; }
+
+    protected abstract ActivityKind Kind { get; }
+
+    public Activity? StartActivityForInvocation(FunctionContext context)
+    {
+        if (!_source.HasListeners())
+        {
+            return null;
+        }
+
+        ActivityContext.TryParse(
+            context.TraceContext.TraceParent,
+            context.TraceContext.TraceState,
+            out var parent);
+
+        // If there is no parent, we still want to create a new root activity.
+        return _source.StartActivity(
+            TraceConstants.FunctionsInvokeActivityName,
+            Kind,
+            parent,
+            tags: GetTelemetryAttributes(context)!);
+    }
+
+    public IEnumerable<KeyValuePair<string, object>> GetTelemetryAttributes(FunctionContext context)
+    {
+        // Live-logs session
+        if (context.TraceContext.Attributes.TryGetValue(TraceConstants.AzFuncLiveLogsSessionIdKey, out var liveId)
+            && !string.IsNullOrWhiteSpace(liveId))
+        {
+            yield return new(TraceConstants.AzFuncLiveLogsSessionIdKey, liveId);
+        }
+
+        // Version-specific tags
+        foreach (var kv in GetVersionSpecificAttributes(context))
+        {
+            yield return kv;
+        }
+    }
+
+    protected abstract IEnumerable<KeyValuePair<string, object>> GetVersionSpecificAttributes(FunctionContext context);
+}