feat(telemetry.serilog): TraceContextEnricher for trace<->log correlation

2026-06-01 07:38:54 -04:00
parent 1344f249d0
commit 70f91a855a
3 changed files with 111 additions and 0 deletions
@@ -0,0 +1,43 @@
+using System.Diagnostics;
+using Serilog.Core;
+using Serilog.Events;
+
+namespace ZB.MOM.WW.Telemetry.Serilog;
+
+/// <summary>
+/// Stamps <c>trace_id</c> and <c>span_id</c> from <see cref="Activity.Current"/> onto every Serilog
+/// log event, enabling a log line to be correlated back to its originating trace in a backend.
+/// When <see cref="Activity.Current"/> is null (no active span — background services, startup,
+/// non-traced paths) the enricher emits nothing; it does NOT inject empty strings or zero values.
+/// </summary>
+public sealed class TraceContextEnricher : ILogEventEnricher
+{
+    /// <summary>Serilog property name carrying the W3C trace id.</summary>
+    public const string TraceIdPropertyName = "trace_id";
+
+    /// <summary>Serilog property name carrying the W3C span id.</summary>
+    public const string SpanIdPropertyName = "span_id";
+
+    /// <summary>
+    /// Adds <c>trace_id</c>/<c>span_id</c> properties from <see cref="Activity.Current"/> when an
+    /// activity is active; otherwise leaves the event untouched.
+    /// </summary>
+    /// <param name="logEvent">The log event to enrich.</param>
+    /// <param name="propertyFactory">Factory used to create the trace-context properties.</param>
+    public void Enrich(LogEvent logEvent, ILogEventPropertyFactory propertyFactory)
+    {
+        ArgumentNullException.ThrowIfNull(logEvent);
+        ArgumentNullException.ThrowIfNull(propertyFactory);
+
+        var activity = Activity.Current;
+        if (activity is null)
+        {
+            return;
+        }
+
+        logEvent.AddPropertyIfAbsent(
+            propertyFactory.CreateProperty(TraceIdPropertyName, activity.TraceId.ToString()));
+        logEvent.AddPropertyIfAbsent(
+            propertyFactory.CreateProperty(SpanIdPropertyName, activity.SpanId.ToString()));
+    }
+}
@@ -64,6 +64,8 @@ public static class ZbSerilogConfig

        enrich.WithProperty(ZbLogEnricherNames.NodeHostname, Environment.MachineName);

+        enrich.With(new TraceContextEnricher());
+
        return loggerConfiguration;
    }
 }