[AzureMonitorExporter] Remove "sampleRate" tag from SamplingResult (#…

…37765)

* remove sampling tag

* remove tag

* pr feedback: if != 100

* add extra check for SampleRate != 100f

* remove nullable from method paramaters. update tests.

sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/src/AzureMonitorTraceExporter.cs

@@ -15,15 +15,17 @@ internal sealed class AzureMonitorTraceExporter : BaseExporter<Activity>
     {
         private readonly ITransmitter _transmitter;
         private readonly string _instrumentationKey;
+        private readonly float _sampleRate; // This value is recorded on TelemetryItem.SampleRate.
         private AzureMonitorResource? _resource;
         private bool _disposed;
 
-        public AzureMonitorTraceExporter(AzureMonitorExporterOptions options) : this(TransmitterFactory.Instance.Get(options))
+        public AzureMonitorTraceExporter(AzureMonitorExporterOptions options) : this(options, TransmitterFactory.Instance.Get(options))
         {
         }
 
-        internal AzureMonitorTraceExporter(ITransmitter transmitter)
+        internal AzureMonitorTraceExporter(AzureMonitorExporterOptions options, ITransmitter transmitter)
         {
+            _sampleRate = (float)Math.Round(options.SamplingRatio * 100);
             _transmitter = transmitter;
             _instrumentationKey = transmitter.InstrumentationKey;
         }
@@ -40,7 +42,7 @@ public override ExportResult Export(in Batch<Activity> batch)
 
             try
             {
-                var telemetryItems = TraceHelper.OtelToAzureMonitorTrace(batch, TraceResource, _instrumentationKey);
+                var telemetryItems = TraceHelper.OtelToAzureMonitorTrace(batch, TraceResource, _instrumentationKey, _sampleRate);
                 if (telemetryItems.Count > 0)
                 {
                     exportResult = _transmitter.TrackAsync(telemetryItems, TelemetryItemOrigin.AzureMonitorTraceExporter, false, CancellationToken.None).EnsureCompleted();

sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/src/Customizations/Models/TelemetryItem.cs

@@ -13,7 +13,7 @@ namespace Azure.Monitor.OpenTelemetry.Exporter.Models
 {
     internal partial class TelemetryItem
     {
-        public TelemetryItem(Activity activity, ref ActivityTagsProcessor activityTagsProcessor, AzureMonitorResource? resource, string instrumentationKey) :
+        public TelemetryItem(Activity activity, ref ActivityTagsProcessor activityTagsProcessor, AzureMonitorResource? resource, string instrumentationKey, float sampleRate) :
             this(activity.GetTelemetryType() == TelemetryType.Request ? "Request" : "RemoteDependency", FormatUtcTimestamp(activity.StartTimeUtc))
         {
             if (activity.ParentSpanId != default)
@@ -60,7 +60,8 @@ public TelemetryItem(Activity activity, ref ActivityTagsProcessor activityTagsPr
 
             SetAuthenticatedUserId(ref activityTagsProcessor);
             SetResourceSdkVersionAndIkey(resource, instrumentationKey);
-            if (AzMonList.GetTagValue(ref activityTagsProcessor.MappedTags, "sampleRate") is float sampleRate)
+
+            if (sampleRate != 100f)
             {
                 SampleRate = sampleRate;
             }
@@ -82,7 +83,11 @@ public TelemetryItem(string name, TelemetryItem telemetryItem, ActivitySpanId ac
             Tags[ContextTagKeys.AiCloudRoleInstance.ToString()] = telemetryItem.Tags[ContextTagKeys.AiCloudRoleInstance.ToString()];
             Tags[ContextTagKeys.AiInternalSdkVersion.ToString()] = SdkVersionUtils.s_sdkVersion;
             InstrumentationKey = telemetryItem.InstrumentationKey;
-            SampleRate = telemetryItem.SampleRate;
+
+            if (telemetryItem.SampleRate != 100f)
+            {
+                SampleRate = telemetryItem.SampleRate;
+            }
         }
 
         public TelemetryItem (LogRecord logRecord, AzureMonitorResource? resource, string instrumentationKey) :

sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/src/Internals/ActivityTagsProcessor.cs

@@ -51,7 +51,6 @@ internal struct ActivityTagsProcessor
             SemanticConventions.AttributeNetHostName,
             SemanticConventions.AttributeComponent,
             "otel.status_code",
-            "sampleRate",
 
             SemanticConventions.AttributeRpcService,
             // required - RPC

sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/src/Internals/ApplicationInsightsSampler.cs

@@ -14,7 +14,7 @@ namespace Azure.Monitor.OpenTelemetry.Exporter.Internals;
 internal sealed class ApplicationInsightsSampler : Sampler
 {
     private static readonly SamplingResult RecordOnlySamplingResult = new(SamplingDecision.RecordOnly);
-    private readonly SamplingResult recordAndSampleSamplingResult;
+    private static readonly SamplingResult RecordAndSampleSamplingResult = new(SamplingDecision.RecordAndSample);
     private readonly float samplingRatio;
 
     /// <summary>
@@ -34,13 +34,6 @@ public ApplicationInsightsSampler(float samplingRatio)
 
         this.samplingRatio = samplingRatio;
         Description = "ApplicationInsightsSampler{" + samplingRatio + "}";
-        var sampleRate = (float)Math.Round(samplingRatio * 100);
-        recordAndSampleSamplingResult = new SamplingResult(
-            SamplingDecision.RecordAndSample,
-            new Dictionary<string, object>
-                {
-                    { "sampleRate", sampleRate },
-                });
     }
 
     /// <summary>
@@ -51,21 +44,21 @@ public ApplicationInsightsSampler(float samplingRatio)
     /// <returns>Returns whether or not we should sample telemetry in the form of a <see cref="SamplingResult"/> class.</returns>
     public override SamplingResult ShouldSample(in SamplingParameters samplingParameters)
     {
-        if (samplingRatio == 0)
+        if (samplingRatio == 1)
         {
-            return RecordOnlySamplingResult;
+            return RecordAndSampleSamplingResult;
         }
 
-        if (samplingRatio == 1)
+        if (samplingRatio == 0)
         {
-            return recordAndSampleSamplingResult;
+            return RecordOnlySamplingResult;
         }
 
         double sampleScore = DJB2SampleScore(samplingParameters.TraceId.ToHexString().ToUpperInvariant());
 
         if (sampleScore < samplingRatio)
         {
-            return recordAndSampleSamplingResult;
+            return RecordAndSampleSamplingResult;
         }
         else
         {

sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/src/Internals/TraceHelper.cs

@@ -19,7 +19,7 @@ internal static class TraceHelper
         private const int Version = 2;
         private const int MaxlinksAllowed = 100;
 
-        internal static List<TelemetryItem> OtelToAzureMonitorTrace(Batch<Activity> batchActivity, AzureMonitorResource? azureMonitorResource, string instrumentationKey)
+        internal static List<TelemetryItem> OtelToAzureMonitorTrace(Batch<Activity> batchActivity, AzureMonitorResource? azureMonitorResource, string instrumentationKey, float sampleRate)
         {
             List<TelemetryItem> telemetryItems = new List<TelemetryItem>();
             TelemetryItem telemetryItem;
@@ -34,7 +34,7 @@ internal static List<TelemetryItem> OtelToAzureMonitorTrace(Batch<Activity> batc
                 try
                 {
                     var activityTagsProcessor = EnumerateActivityTags(activity);
-                    telemetryItem = new TelemetryItem(activity, ref activityTagsProcessor, azureMonitorResource, instrumentationKey);
+                    telemetryItem = new TelemetryItem(activity, ref activityTagsProcessor, azureMonitorResource, instrumentationKey, sampleRate);
 
                     // Check for Exceptions events
                     if (activity.Events.Any())

sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/tests/Azure.Monitor.OpenTelemetry.Exporter.Tests/CommonTestFramework/AzureMonitorExporterTestExtensions.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using Azure.Monitor.OpenTelemetry.Exporter.Internals;
 using Azure.Monitor.OpenTelemetry.Exporter.Models;
 using OpenTelemetry;
 using OpenTelemetry.Logs;
@@ -69,7 +70,7 @@ internal static MeterProviderBuilder AddAzureMonitorMetricExporterForTest(this M
         /// <summary>
         /// Extension methods to simplify registering of <see cref="AzureMonitorTraceExporter"/> with <see cref="MockTransmitter"/> for unit tests.
         /// </summary>
-        internal static TracerProviderBuilder AddAzureMonitorTraceExporterForTest(this TracerProviderBuilder builder, out List<TelemetryItem> telemetryItems)
+        internal static TracerProviderBuilder AddAzureMonitorTraceExporterForTest(this TracerProviderBuilder builder, out List<TelemetryItem> telemetryItems, Action<AzureMonitorExporterOptions>? configure = null)
         {
             if (builder == null)
             {
@@ -78,7 +79,12 @@ internal static TracerProviderBuilder AddAzureMonitorTraceExporterForTest(this T
 
             telemetryItems = new List<TelemetryItem>();
 
-            return builder.AddProcessor(new SimpleActivityExportProcessor(new AzureMonitorTraceExporter(new MockTransmitter(telemetryItems))));
+            var options = new AzureMonitorExporterOptions();
+            configure?.Invoke(options);
+
+            builder.SetSampler(new ApplicationInsightsSampler(options.SamplingRatio));
+
+            return builder.AddProcessor(new SimpleActivityExportProcessor(new AzureMonitorTraceExporter(options, new MockTransmitter(telemetryItems))));
         }
     }
 }

sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/tests/Azure.Monitor.OpenTelemetry.Exporter.Tests/OfflineStorageTests.cs

@@ -298,7 +298,7 @@ private static Activity CreateActivity(string activityName)
         private static TelemetryItem CreateTelemetryItem(Activity activity)
         {
             var activityTagsProcessor = TraceHelper.EnumerateActivityTags(activity);
-            return new TelemetryItem(activity, ref activityTagsProcessor, null, string.Empty);
+            return new TelemetryItem(activity, ref activityTagsProcessor, null, string.Empty, 1.0f);
         }
 
         private class MockFileProvider : PersistentBlobProvider

sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/tests/Azure.Monitor.OpenTelemetry.Exporter.Tests/SampleRateTests.cs

@@ -35,65 +35,40 @@ static SampleRateTests()
 
         [Theory]
         [InlineData(50.0F)]
-        [InlineData("somestring")]
-        [InlineData(null)]
-        [InlineData("")]
-        public void ValidateSampleRateForEventException(object SampleRate)
+        public void ValidateSampleRateForEventException(float sampleRate)
         {
             using ActivitySource activitySource = new ActivitySource(ActivitySourceName);
 
-            // Valid SampleRate.
             using var activity = activitySource.StartActivity(
                 ActivityName,
                 ActivityKind.Client,
                 parentContext: default,
-                startTime: DateTime.UtcNow,
-                tags: new Dictionary<string, object?>() { ["sampleRate"] = SampleRate });
+                startTime: DateTime.UtcNow);
 
             Assert.NotNull(activity);
             var activityTagsProcessor = TraceHelper.EnumerateActivityTags(activity);
-            var telemetryItem = new TelemetryItem(activity, ref activityTagsProcessor, null, "00000000-0000-0000-0000-000000000000");
+            var telemetryItem = new TelemetryItem(activity, ref activityTagsProcessor, null, "00000000-0000-0000-0000-000000000000", sampleRate);
             var expTelemetryItem = new TelemetryItem("Exception", telemetryItem, default, default, default);
-
-            if (SampleRate is float)
-            {
-                Assert.Equal(SampleRate, expTelemetryItem.SampleRate);
-            }
-            else
-            {
-                Assert.Null(expTelemetryItem.SampleRate);
-            }
+            Assert.Equal(sampleRate, expTelemetryItem.SampleRate);
         }
 
         [Theory]
         [InlineData(50.0F)]
-        [InlineData("somestring")]
-        [InlineData(null)]
-        [InlineData("")]
-        public void ValidateSampleRateInTelemetry(object SampleRate)
+        public void ValidateSampleRateInTelemetry(float sampleRate)
         {
             using ActivitySource activitySource = new ActivitySource(ActivitySourceName);
 
-            // Valid SampleRate.
             using var activity = activitySource.StartActivity(
                 ActivityName,
                 ActivityKind.Client,
                 parentContext: default,
-                startTime: DateTime.UtcNow,
-                tags: new Dictionary<string, object?>() { ["sampleRate"] = SampleRate });
+                startTime: DateTime.UtcNow);
 
             Assert.NotNull(activity);
             var activityTagsProcessor = TraceHelper.EnumerateActivityTags(activity);
-            var telemetryItem = new TelemetryItem(activity, ref activityTagsProcessor, null, "00000000-0000-0000-0000-000000000000");
+            var telemetryItem = new TelemetryItem(activity, ref activityTagsProcessor, null, "00000000-0000-0000-0000-000000000000", sampleRate);
 
-            if (SampleRate is float)
-            {
-                Assert.Equal(SampleRate, telemetryItem.SampleRate);
-            }
-            else
-            {
-                Assert.Null(telemetryItem.SampleRate);
-            }
+            Assert.Equal(sampleRate, telemetryItem.SampleRate);
         }
 
         [Fact]
@@ -102,8 +77,7 @@ public void SampleRateE2ETest()
             using var activitySource = new ActivitySource(ActivitySourceName);
             using var tracerProvider = Sdk.CreateTracerProviderBuilder()
                 .AddSource(ActivitySourceName)
-                .SetSampler(new ApplicationInsightsSampler(samplingRatio: 1.0F))
-                .AddAzureMonitorTraceExporterForTest(out List<TelemetryItem> telemetryItems)
+                .AddAzureMonitorTraceExporterForTest(out List<TelemetryItem> telemetryItems, options => options.SamplingRatio = 1.0F)
                 .Build();
 
             using (var activity = activitySource.StartActivity("SayHello"))
@@ -113,7 +87,7 @@ public void SampleRateE2ETest()
             tracerProvider?.ForceFlush();
 
             Assert.NotEmpty(telemetryItems);
-            Assert.Equal(100F, telemetryItems.Last()!.SampleRate);
+            Assert.Null(telemetryItems.Last()!.SampleRate);
         }
 
         [Fact]
@@ -122,8 +96,7 @@ public void NoTelemetryCreatedOnZeroSampleRate()
             using var activitySource = new ActivitySource(ActivitySourceName);
             using var tracerProvider = Sdk.CreateTracerProviderBuilder()
                 .AddSource(ActivitySourceName)
-                .SetSampler(new ApplicationInsightsSampler(samplingRatio: 0.0F))
-                .AddAzureMonitorTraceExporterForTest(out List<TelemetryItem> telemetryItems)
+                .AddAzureMonitorTraceExporterForTest(out List<TelemetryItem> telemetryItems, options => options.SamplingRatio = 0.0F)
                 .Build();
 
             using (var activity = activitySource.StartActivity("SayHello"))

sdk/monitor/Azure.Monitor.OpenTelemetry.Exporter/tests/Azure.Monitor.OpenTelemetry.Exporter.Tests/StandardMetricTests.cs

@@ -36,7 +36,7 @@ public void ValidateRequestDurationMetric()
                 .SetResourceBuilder(ResourceBuilder.CreateDefault().AddAttributes(resourceAttributes))
                 .AddSource(nameof(StandardMetricTests.ValidateRequestDurationMetric))
                 .AddProcessor(standardMetricCustomProcessor)
-                .AddProcessor(new BatchActivityExportProcessor(new AzureMonitorTraceExporter(new MockTransmitter(traceTelemetryItems))))
+                .AddProcessor(new BatchActivityExportProcessor(new AzureMonitorTraceExporter(new AzureMonitorExporterOptions(), new MockTransmitter(traceTelemetryItems))))
                 .Build();
 
             using (var activity = activitySource.StartActivity("Test", ActivityKind.Server))
@@ -85,7 +85,7 @@ public void ValidateRequestDurationMetricNew()
                 .SetResourceBuilder(ResourceBuilder.CreateDefault().AddAttributes(resourceAttributes))
                 .AddSource(nameof(StandardMetricTests.ValidateRequestDurationMetric))
                 .AddProcessor(standardMetricCustomProcessor)
-                .AddProcessor(new BatchActivityExportProcessor(new AzureMonitorTraceExporter(new MockTransmitter(traceTelemetryItems))))
+                .AddProcessor(new BatchActivityExportProcessor(new AzureMonitorTraceExporter(new AzureMonitorExporterOptions(), new MockTransmitter(traceTelemetryItems))))
                 .Build();
 
             using (var activity = activitySource.StartActivity("Test", ActivityKind.Server))
@@ -134,7 +134,7 @@ public void ValidateDependencyDurationMetric()
                 .SetResourceBuilder(ResourceBuilder.CreateDefault().AddAttributes(resourceAttributes))
                 .AddSource(nameof(StandardMetricTests.ValidateDependencyDurationMetric))
                 .AddProcessor(standardMetricCustomProcessor)
-                .AddProcessor(new BatchActivityExportProcessor(new AzureMonitorTraceExporter(new MockTransmitter(traceTelemetryItems))))
+                .AddProcessor(new BatchActivityExportProcessor(new AzureMonitorTraceExporter(new AzureMonitorExporterOptions(), new MockTransmitter(traceTelemetryItems))))
                 .Build();
 
             using (var activity = activitySource.StartActivity("Test", ActivityKind.Client))
@@ -189,7 +189,7 @@ public void ValidateDependencyDurationMetricNew()
                 .SetResourceBuilder(ResourceBuilder.CreateDefault().AddAttributes(resourceAttributes))
                 .AddSource(nameof(StandardMetricTests.ValidateDependencyDurationMetric))
                 .AddProcessor(standardMetricCustomProcessor)
-                .AddProcessor(new BatchActivityExportProcessor(new AzureMonitorTraceExporter(new MockTransmitter(traceTelemetryItems))))
+                .AddProcessor(new BatchActivityExportProcessor(new AzureMonitorTraceExporter(new AzureMonitorExporterOptions(), new MockTransmitter(traceTelemetryItems))))
                 .Build();
 
             using (var activity = activitySource.StartActivity("Test", ActivityKind.Client))
@@ -242,7 +242,7 @@ public void ValidateNullStatusCode(ActivityKind kind)
                 .SetSampler(new AlwaysOnSampler())
                 .AddSource(nameof(StandardMetricTests.ValidateNullStatusCode))
                 .AddProcessor(standardMetricCustomProcessor)
-                .AddProcessor(new BatchActivityExportProcessor(new AzureMonitorTraceExporter(new MockTransmitter(traceTelemetryItems))))
+                .AddProcessor(new BatchActivityExportProcessor(new AzureMonitorTraceExporter(new AzureMonitorExporterOptions(), new MockTransmitter(traceTelemetryItems))))
                 .Build();
 
             using (var activity = activitySource.StartActivity("Test", kind))
@@ -290,7 +290,7 @@ public void ValidateNullStatusCodeNew(ActivityKind kind)
                 .SetSampler(new AlwaysOnSampler())
                 .AddSource(nameof(StandardMetricTests.ValidateNullStatusCode))
                 .AddProcessor(standardMetricCustomProcessor)
-                .AddProcessor(new BatchActivityExportProcessor(new AzureMonitorTraceExporter(new MockTransmitter(traceTelemetryItems))))
+                .AddProcessor(new BatchActivityExportProcessor(new AzureMonitorTraceExporter(new AzureMonitorExporterOptions(), new MockTransmitter(traceTelemetryItems))))
                 .Build();
 
             using (var activity = activitySource.StartActivity("Test", kind))