Add option to record exceptions

src/OpenTelemetry.Instrumentation.Hangfire/HangfireInstrumentationOptions.cs

@@ -0,0 +1,31 @@
+// <copyright file="HangfireInstrumentationOptions.cs" company="OpenTelemetry Authors">
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// </copyright>
+
+namespace OpenTelemetry.Trace;
+
+/// <summary>
+/// Options for hangfire jobs instrumentation.
+/// </summary>
+public class HangfireInstrumentationOptions
+{
+    /// <summary>
+    /// Gets or sets a value indicating whether the exception will be recorded as ActivityEvent or not.
+    /// </summary>
+    /// <remarks>
+    /// https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/semantic_conventions/exceptions.md.
+    /// </remarks>
+    public bool RecordException { get; set; }
+}

src/OpenTelemetry.Instrumentation.Hangfire/Implementation/HangfireInstrumentationJobFilterAttribute.cs

@@ -23,9 +23,17 @@ namespace OpenTelemetry.Instrumentation.Hangfire.Implementation;
 using global::Hangfire.Common;
 using global::Hangfire.Server;
 using OpenTelemetry.Context.Propagation;
+using OpenTelemetry.Trace;
 
 internal class HangfireInstrumentationJobFilterAttribute : JobFilterAttribute, IServerFilter, IClientFilter
 {
+    private readonly HangfireInstrumentationOptions options;
+
+    public HangfireInstrumentationJobFilterAttribute(HangfireInstrumentationOptions options)
+    {
+        this.options = options;
+    }
+
     public void OnPerforming(PerformingContext performingContext)
     {
         // Short-circuit if nobody is listening
@@ -75,6 +83,11 @@ public void OnPerformed(PerformedContext performedContext)
                 activity.SetStatus(ActivityStatusCode.Error, performedContext.Exception.Message);
             }
 
+            if (performedContext.Exception != null && this.options.RecordException)
+            {
+                activity.RecordException(performedContext.Exception);
+            }
+
             activity.Dispose();
         }
     }

src/OpenTelemetry.Instrumentation.Hangfire/TracerProviderBuilderExtensions.cs

@@ -16,6 +16,7 @@
 
 namespace OpenTelemetry.Trace;
 
+using System;
 using OpenTelemetry.Instrumentation.Hangfire.Implementation;
 using OpenTelemetry.Internal;
 
@@ -33,7 +34,25 @@ public static TracerProviderBuilder AddHangfireInstrumentation(this TracerProvid
     {
         Guard.ThrowIfNull(builder);
 
-        Hangfire.GlobalJobFilters.Filters.Add(new HangfireInstrumentationJobFilterAttribute());
+        return builder.AddHangfireInstrumentation(null);
+    }
+
+    /// <summary>
+    /// Adds Hangfire instrumentation to the tracer provider.
+    /// </summary>
+    /// <param name="builder"><see cref="TracerProviderBuilder"/> being configured.</param>
+    /// <param name="configureHangfireInstrumentationOptions">Callback action for configuring <see cref="HangfireInstrumentationOptions"/>.</param>
+    /// <returns>The instance of <see cref="TracerProviderBuilder"/> to chain the calls.</returns>
+    public static TracerProviderBuilder AddHangfireInstrumentation(
+        this TracerProviderBuilder builder,
+        Action<HangfireInstrumentationOptions> configureHangfireInstrumentationOptions)
+    {
+        Guard.ThrowIfNull(builder);
+
+        var options = new HangfireInstrumentationOptions();
+        configureHangfireInstrumentationOptions?.Invoke(options);
+
+        Hangfire.GlobalJobFilters.Filters.Add(new HangfireInstrumentationJobFilterAttribute(options));
 
         return builder.AddSource(HangfireInstrumentation.ActivitySourceName);
     }

test/OpenTelemetry.Instrumentation.Hangfire.Tests/HangfireInstrumentationJobFilterAttributeTests.cs

@@ -77,6 +77,31 @@ public async Task Should_Create_Activity_With_Status_Error_When_Job_Failed()
         Assert.Equal(ActivityKind.Internal, activity.Kind);
         Assert.Equal(ActivityStatusCode.Error, activity.Status);
         Assert.NotNull(activity.StatusDescription);
+        Assert.Empty(activity.Events);
+    }
+
+    [Fact]
+    public async Task Should_Create_Activity_With_Exception_Event_When_Job_Failed_And_Record_Exception_Is_True()
+    {
+        // Arrange
+        var exportedItems = new List<Activity>();
+        using var tel = Sdk.CreateTracerProviderBuilder()
+            .AddHangfireInstrumentation(options => options.RecordException = true)
+            .AddInMemoryExporter(exportedItems)
+            .Build();
+
+        // Act
+        var jobId = BackgroundJob.Enqueue<TestJob>(x => x.ThrowException());
+        await this.WaitJobProcessedAsync(jobId, 5);
+
+        // Assert
+        Assert.Single(exportedItems, i => i.GetTagItem("job.id") as string == jobId);
+        var activity = exportedItems.Single(i => i.GetTagItem("job.id") as string == jobId);
+        Assert.Contains("JOB TestJob.ThrowException", activity.DisplayName);
+        Assert.Equal(ActivityKind.Internal, activity.Kind);
+        Assert.Equal(ActivityStatusCode.Error, activity.Status);
+        Assert.NotNull(activity.StatusDescription);
+        Assert.Single(activity.Events, evt => evt.Name == "exception");
     }
 
     private async Task WaitJobProcessedAsync(string jobId, int timeToWaitInSeconds)