Add ActivityPropagationHandler test

src/ReverseProxy/Telemetry/ActivityPropagationHandler.cs

@@ -1,6 +1,5 @@
-// 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.
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
 
 using System;
 using System.Collections.Generic;

test/ReverseProxy.Tests/Common/MockHttpHandler.cs

@@ -0,0 +1,31 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace Microsoft.ReverseProxy.Common.Tests
+{
+    internal class MockHttpHandler : HttpMessageHandler
+    {
+        private readonly Func<HttpRequestMessage, CancellationToken, Task<HttpResponseMessage>> _func;
+
+        public MockHttpHandler(Func<HttpRequestMessage, CancellationToken, Task<HttpResponseMessage>> func)
+        {
+            _func = func ?? throw new ArgumentNullException(nameof(func));
+        }
+
+        public static HttpMessageInvoker CreateClient(Func<HttpRequestMessage, CancellationToken, Task<HttpResponseMessage>> func)
+        {
+            var handler = new MockHttpHandler(func);
+            return new HttpMessageInvoker(handler);
+        }
+
+        protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
+        {
+            return _func(request, cancellationToken);
+        }
+    }
+}

test/ReverseProxy.Tests/Configuration/ConfigurationConfigProviderTests.cs

@@ -599,6 +599,7 @@ private void VerifyValidAbstractConfig(ConfigurationData validConfig, X509Certif
             Assert.Equal(validConfig.Clusters["cluster1"].SessionAffinity.Settings, abstractCluster1.SessionAffinity.Settings);
             Assert.Same(certificate, abstractCluster1.HttpClient.ClientCertificate);
             Assert.Equal(validConfig.Clusters["cluster1"].HttpClient.MaxConnectionsPerServer, abstractCluster1.HttpClient.MaxConnectionsPerServer);
+            Assert.Equal(validConfig.Clusters["cluster1"].HttpClient.PropagateActivityContext, abstractCluster1.HttpClient.PropagateActivityContext);
             Assert.Equal(SslProtocols.Tls11 | SslProtocols.Tls12, abstractCluster1.HttpClient.SslProtocols);
             Assert.Equal(validConfig.Clusters["cluster1"].HttpClient.DangerousAcceptAnyServerCertificate, abstractCluster1.HttpClient.DangerousAcceptAnyServerCertificate);
             Assert.Equal(validConfig.Clusters["cluster1"].HttpRequest.RequestTimeout, abstractCluster1.HttpRequest.RequestTimeout);

test/ReverseProxy.Tests/Service/Proxy/HttpProxyTests.cs

@@ -1606,27 +1606,6 @@ private static string StreamToString(Stream stream)
             return reader.ReadToEnd();
         }
 
-        private class MockHttpHandler : HttpMessageHandler
-        {
-            private readonly Func<HttpRequestMessage, CancellationToken, Task<HttpResponseMessage>> func;
-
-            private MockHttpHandler(Func<HttpRequestMessage, CancellationToken, Task<HttpResponseMessage>> func)
-            {
-                this.func = func ?? throw new ArgumentNullException(nameof(func));
-            }
-
-            public static HttpMessageInvoker CreateClient(Func<HttpRequestMessage, CancellationToken, Task<HttpResponseMessage>> func)
-            {
-                var handler = new MockHttpHandler(func);
-                return new HttpMessageInvoker(handler);
-            }
-
-            protected override Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken)
-            {
-                return func(request, cancellationToken);
-            }
-        }
-
         private class DuplexStream : Stream
         {
             public DuplexStream(Stream readStream, Stream writeStream)

test/ReverseProxy.Tests/Service/Proxy/Infrastructure/ActivityPropagationHandlerTests.cs

@@ -0,0 +1,68 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+using System.Diagnostics;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.ReverseProxy.Common.Tests;
+using Microsoft.ReverseProxy.Telemetry;
+using Xunit;
+
+namespace Microsoft.ReverseProxy.Service.Proxy.Tests
+{
+    public class ActivityPropagationHandlerTests
+    {
+        [Theory]
+        [InlineData(true)]
+        [InlineData(false)]
+        public async Task SendAsync_CurrentActivitySet_RequestHeadersSet(bool useW3CFormat)
+        {
+            const string TraceStateString = "CustomTraceStateString";
+            string expectedId = null;
+
+            var invoker = new HttpMessageInvoker(new ActivityPropagationHandler(new MockHttpHandler(
+                (HttpRequestMessage request, CancellationToken cancellationToken) =>
+                {
+                    var headers = request.Headers;
+
+                    Assert.True(headers.TryGetValues(useW3CFormat ? "traceparent" : "Request-Id", out var values));
+                    Assert.Equal(expectedId, Assert.Single(values));
+
+                    if (useW3CFormat)
+                    {
+                        Assert.True(headers.TryGetValues("tracestate", out values));
+                        Assert.Equal(TraceStateString, Assert.Single(values));
+                    }
+
+                    Assert.True(headers.TryGetValues("Correlation-Context", out values));
+                    Assert.Equal("foo=bar", Assert.Single(values));
+
+                    return Task.FromResult<HttpResponseMessage>(null);
+                })));
+
+            var activity = new Activity("CustomOperation");
+
+            if (useW3CFormat)
+            {
+                activity.SetIdFormat(ActivityIdFormat.W3C);
+                activity.TraceStateString = TraceStateString;
+                activity.SetParentId("00-01234567890123456789012345678901-0123456789012345-01");
+            }
+            else
+            {
+                activity.SetIdFormat(ActivityIdFormat.Hierarchical);
+                activity.SetParentId("|root");
+            }
+
+            activity.AddBaggage("foo", "bar");
+
+            activity.Start();
+            expectedId = activity.Id;
+
+            await invoker.SendAsync(new HttpRequestMessage(), CancellationToken.None);
+
+            activity.Stop();
+        }
+    }
+}