Add testcase for refresh activity

src/Microsoft.Extensions.Configuration.AzureAppConfiguration/AzureAppConfigurationOptions.cs

@@ -119,6 +119,11 @@ internal IEnumerable<IKeyValueAdapter> Adapters
         /// </summary>
         internal IConfigurationSettingPageIterator ConfigurationSettingPageIterator { get; set; }
 
+        /// <summary>
+        /// For use in tests only. An optional activity source name to specify the activity source used by the configuration provider.
+        /// </summary>
+        internal string ActivitySourceName { get; set; }
+
         /// <summary>
         /// An optional timespan value to set the minimum backoff duration to a value other than the default.
         /// </summary>

src/Microsoft.Extensions.Configuration.AzureAppConfiguration/AzureAppConfigurationProvider.cs

@@ -23,7 +23,7 @@ namespace Microsoft.Extensions.Configuration.AzureAppConfiguration
 {
     internal class AzureAppConfigurationProvider : ConfigurationProvider, IConfigurationRefresher, IDisposable
     {
-        private readonly ActivitySource _activitySource = new ActivitySource(ActivityNames.AzureAppConfigurationActivitySource);
+        private readonly ActivitySource _activitySource;
         private bool _optional;
         private bool _isInitialLoadComplete = false;
         private bool _isAssemblyInspected;
@@ -151,6 +151,8 @@ public AzureAppConfigurationProvider(IConfigurationClientManager configClientMan
             {
                 SetRequestTracingOptions();
             }
+
+            _activitySource = new ActivitySource(options.ActivitySourceName ?? ActivityNames.AzureAppConfigurationActivitySource);
         }
 
         /// <summary>
@@ -159,7 +161,7 @@ public AzureAppConfigurationProvider(IConfigurationClientManager configClientMan
         public override void Load()
         {
             var watch = Stopwatch.StartNew();
-            using Activity activity = _activitySource.StartActivity(ActivityNames.Load);
+            using Activity activity = _activitySource?.StartActivity(ActivityNames.Load);
             try
             {
                 using var startupCancellationTokenSource = new CancellationTokenSource(_options.Startup.Timeout);
@@ -259,7 +261,7 @@ public async Task RefreshAsync(CancellationToken cancellationToken)
                         return;
                     }
 
-                    using Activity activity = _activitySource.StartActivity(ActivityNames.Refresh);
+                    using Activity activity = _activitySource?.StartActivity(ActivityNames.Refresh);
                     // Check if initial configuration load had failed
                     if (_mappedData == null)
                     {
@@ -1422,7 +1424,7 @@ private async Task ProcessKeyValueChangesAsync(
         public void Dispose()
         {
             (_configClientManager as ConfigurationClientManager)?.Dispose();
-            _activitySource.Dispose();
+            _activitySource?.Dispose();
         }
     }
 }

tests/Tests.AzureAppConfiguration/RefreshTests.cs

@@ -12,6 +12,7 @@
 using Moq;
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
@@ -1218,6 +1219,68 @@ MockAsyncPageable GetTestKeys(SettingSelector selector, CancellationToken ct)
             Assert.Null(config["FeatureManagement:MyFeature"]);
         }
 
+        [Fact]
+        public async Task RefreshTests_StartsRefreshActivity()
+        {
+            string activitySourceName = Guid.NewGuid().ToString();
+
+            var _activities = new List<Activity>();
+            var _activityListener = new ActivityListener
+            {
+                ShouldListenTo = source => source.Name == activitySourceName,
+                Sample = (ref ActivityCreationOptions<ActivityContext> options) => ActivitySamplingResult.AllData,
+                ActivityStarted = activity => _activities.Add(activity),
+            };
+            ActivitySource.AddActivityListener(_activityListener);
+
+            IConfigurationRefresher refresher = null;
+            var mockClient = GetMockConfigurationClient();
+
+            var mockAsyncPageable = new MockAsyncPageable(_kvCollection);
+
+            mockClient.Setup(c => c.GetConfigurationSettingsAsync(It.IsAny<SettingSelector>(), It.IsAny<CancellationToken>()))
+                .Callback(() => mockAsyncPageable.UpdateCollection(_kvCollection))
+                .Returns(mockAsyncPageable);
+
+            var config = new ConfigurationBuilder()
+                .AddAzureAppConfiguration(options =>
+                {
+                    options.ClientManager = TestHelpers.CreateMockedConfigurationClientManager(mockClient.Object);
+                    options.Select("TestKey*", "label");
+                    options.ConfigurationSettingPageIterator = new MockConfigurationSettingPageIterator();
+                    options.ConfigureRefresh(refreshOptions =>
+                    {
+                        refreshOptions.RegisterAll()
+                            .SetRefreshInterval(TimeSpan.FromSeconds(1));
+                    });
+                    options.ActivitySourceName = activitySourceName;
+
+                    refresher = options.GetRefresher();
+                })
+                .Build();
+
+            Assert.Single(_activities);
+            Assert.Contains(_activities, a => a.OperationName == "Load");
+
+            // Wait for the cache to expire
+            await Task.Delay(1500);
+            await refresher.RefreshAsync();
+
+            Assert.Equal(2, _activities.Count);
+            Assert.Equal("Refresh", _activities.Last().OperationName);
+
+            await refresher.RefreshAsync();
+            Assert.Equal(2, _activities.Count); // only start refresh activity when real refresh happens
+
+            // Wait for the cache to expire
+            await Task.Delay(1500);
+            await refresher.RefreshAsync();
+            Assert.Equal(3, _activities.Count);
+            Assert.Equal("Refresh", _activities.Last().OperationName);
+
+            _activityListener.Dispose();
+        }
+
 #if NET8_0
         [Fact]
         public void RefreshTests_ChainedConfigurationProviderUsedAsRootForRefresherProvider()

tests/Tests.AzureAppConfiguration/Tests.cs

@@ -10,8 +10,10 @@
 using Moq;
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.Linq;
 using System.Threading;
+using System.Threading.Tasks;
 using Xunit;
 
 namespace Tests.AzureAppConfiguration
@@ -346,5 +348,35 @@ public void TestKeepSelectorPrecedenceAfterDedup()
 
             Assert.True(config["message"] == "message from dev label");
         }
+
+        [Fact]
+        public void TestActivitySource()
+        {
+            var _activities = new List<Activity>();
+            var _activityListener = new ActivityListener
+            {
+                ShouldListenTo = source => source.Name == "Microsoft.Extensions.Configuration.AzureAppConfiguration",
+                Sample = (ref ActivityCreationOptions<ActivityContext> options) => ActivitySamplingResult.AllData,
+                ActivityStarted = activity => _activities.Add(activity),
+            };
+            ActivitySource.AddActivityListener(_activityListener);
+
+            var mockResponse = new Mock<Response>();
+            var mockClient = new Mock<ConfigurationClient>(MockBehavior.Strict);
+
+            mockClient.Setup(c => c.GetConfigurationSettingsAsync(It.IsAny<SettingSelector>(), It.IsAny<CancellationToken>()))
+                .Returns(new MockAsyncPageable(_kvCollectionPageOne));
+
+            mockClient.Setup(c => c.GetConfigurationSettingAsync(It.IsAny<string>(), It.IsAny<string>(), It.IsAny<CancellationToken>()))
+                .ReturnsAsync(Response.FromValue(_kv, mockResponse.Object));
+
+            var config = new ConfigurationBuilder()
+                .AddAzureAppConfiguration(options => options.ClientManager = TestHelpers.CreateMockedConfigurationClientManager(mockClient.Object))
+                .Build();
+
+            Assert.Contains(_activities, a => a.OperationName == "Load");
+
+            _activityListener.Dispose();
+        }
     }
 }