[2.11.0-beta1] experimental deferred request properties (#1198)

* squash changes

* resolve merge conflict

* save worknig test

* this works

* finished, should refactor

* move HttpContext to separate helper class

* TODO

* fix compile

* code review concerns

* change Base SDK version to 2.11 beta1

* Switch tests from DisableTrackingProperties to Experimental Features

CHANGELOG.md

@@ -4,7 +4,7 @@
  - [Add support for Event Counter collection.](https://github.com/Microsoft/ApplicationInsights-dotnet-server/issues/1222)
  - [Support for Process CPU and Process Memory perf counters in all platforms including Linux.](https://github.com/microsoft/ApplicationInsights-dotnet-server/issues/1189)
  - [Azure Web App for Windows Containers to use regular PerfCounter mechanism.](https://github.com/microsoft/ApplicationInsights-dotnet-server/pull/1167) 
- - [Defer populating RequestTelemetry properties.](https://github.com/Microsoft/ApplicationInsights-dotnet-server/issues/1173) 
+ - Experimental: [Defer populating RequestTelemetry properties.](https://github.com/Microsoft/ApplicationInsights-dotnet-server/issues/1173) 
  - [Fix: Replaced non-threadsafe HashSet with ConcurrentDictionary in RequestTrackingTelemetryModule.IsHandlerToFilter](https://github.com/microsoft/ApplicationInsights-dotnet-server/pull/1211)
  - SDL: [Guard against malicious headers in quickpulse](https://github.com/microsoft/ApplicationInsights-dotnet-server/pull/1191)
 

Src/Common/Common.projitems

@@ -17,6 +17,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)ExceptionUtilities.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)GuidExtensions.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)HeadersUtilities.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)ExperimentalConstants.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)InjectionGuardConstants.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)PropertyFetcher.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)RequestResponseHeaders.cs" />

Src/Common/ExperimentalConstants.cs

@@ -0,0 +1,21 @@
+#if DEPENDENCY_COLLECTOR
+    namespace Microsoft.ApplicationInsights.Common
+#else
+    namespace Microsoft.ApplicationInsights.Common.Internal
+#endif
+{
+    /// <summary>
+    /// These values are listed to guard against malicious injections by limiting the max size allowed in an HTTP Response.
+    /// These max limits are intentionally exaggerated to allow for unexpected responses, while still guarding against unreasonably large responses.
+    /// Example: While a 32 character response may be expected, 50 characters may be permitted while a 10,000 character response would be unreasonable and malicious.
+    /// </summary>
+    internal static class ExperimentalConstants
+    {
+        /// <summary>
+        /// This is used to defer setting properties on RequestTelemetry until after Sampling.
+        /// QuickPulse expects these properties so we have to set them here as well.
+        /// Used to set QuickPulseTelemetryProcessor.EvaluateDisabledTrackingProperties and RequestTrackingTelemetryModule.DisableTrackingProperties.
+        /// </summary>
+        public const string DeferRequestTrackingProperties = nameof(DeferRequestTrackingProperties);
+    }
+}

Src/DependencyCollector/DependencyCollector/DependencyCollector.csproj

@@ -26,7 +26,7 @@
     <PackageReference Include="StyleCop.Analyzers" Version="1.1.118">
       <PrivateAssets>All</PrivateAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.CodeAnalysis.FxCopAnalyzers" Version="2.9.2" >
+    <PackageReference Include="Microsoft.CodeAnalysis.FxCopAnalyzers" Version="2.9.2">
     <PrivateAssets>All</PrivateAssets>
     </PackageReference>
     <PackageReference Include="MicroBuild.Core" Version="0.3.0">

Src/DependencyCollector/Net45.Tests/DependencyCollector.Net45.Tests.csproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="15.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildProjectDirectory), 'Test.props'))\Test.props" />
   <PropertyGroup>
@@ -90,4 +90,4 @@
   <Import Project="$(VSToolsPath)\TeamTest\Microsoft.TestTools.targets" Condition="Exists('$(VSToolsPath)\TeamTest\Microsoft.TestTools.targets')" />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory), 'Common.targets'))\Common.targets" />
-</Project>
+</Project>

Src/DependencyCollector/Net45.Tests/packages.config

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <packages>
   <package id="Microsoft.ApplicationInsights" version="2.11.0-beta1" targetFramework="net451" />
   <package id="StyleCop.Analyzers" version="1.0.2" targetFramework="net451" developmentDependency="true" />
@@ -9,4 +9,4 @@
   <package id="xunit.core" version="2.1.0" targetFramework="net451" />
   <package id="xunit.extensibility.core" version="2.1.0" targetFramework="net451" />
   <package id="xunit.extensibility.execution" version="2.1.0" targetFramework="net451" />
-</packages>
+</packages>

Src/HostingStartup/HostingStartup.Net45.Tests/HostingStartup.Net45.Tests.csproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="15.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildProjectDirectory), 'Test.props'))\Test.props" />
   <PropertyGroup>
@@ -85,4 +85,4 @@
   <Import Project="$(VSToolsPath)\TeamTest\Microsoft.TestTools.targets" Condition="Exists('$(VSToolsPath)\TeamTest\Microsoft.TestTools.targets')" />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory), 'Common.targets'))\Common.targets" />
-</Project>
+</Project>

Src/HostingStartup/HostingStartup.Net45.Tests/packages.config

@@ -1,7 +1,7 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <packages>
   <package id="MicroBuild.Core" version="0.3.0" targetFramework="net45" developmentDependency="true" />
   <package id="Microsoft.ApplicationInsights" version="2.11.0-beta1" targetFramework="net45" />
   <package id="StyleCop.Analyzers" version="1.0.2" targetFramework="net45" developmentDependency="true" />
   <package id="System.Diagnostics.DiagnosticSource" version="4.5.0" targetFramework="net45" />
-</packages>
+</packages>

Src/HostingStartup/HostingStartup/HostingStartup.csproj

@@ -26,7 +26,7 @@
     <PackageReference Include="StyleCop.Analyzers" Version="1.1.118">
       <PrivateAssets>All</PrivateAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.CodeAnalysis.FxCopAnalyzers" Version="2.9.2" >
+    <PackageReference Include="Microsoft.CodeAnalysis.FxCopAnalyzers" Version="2.9.2">
       <PrivateAssets>All</PrivateAssets>
     </PackageReference>
     <PackageReference Include="MicroBuild.Core" Version="0.3.0">

Src/PerformanceCollector/Perf.NetFull.Tests/Perf.NetFull.Tests.csproj

@@ -48,6 +48,7 @@
     <Reference Include="System.Net" />
     <Reference Include="System.Net.Http" />
     <Reference Include="System.Runtime.Serialization" />
+    <Reference Include="System.Web" />
     <Reference Include="System.XML" />
   </ItemGroup>
   <ItemGroup>

Src/PerformanceCollector/Perf.Shared.Tests/Helpers/HttpContextHelper.cs

@@ -0,0 +1,109 @@
+namespace Microsoft.ApplicationInsights.Extensibility.PerfCounterCollector.Tests.Helpers
+{
+#if NET45
+    using System;
+    using System.Collections.Generic;
+    using System.Globalization;
+    using System.IO;
+    using System.Threading;
+    using System.Web;
+    using System.Web.Hosting;
+#endif
+
+    public static class HttpContextHelper
+    {
+#if NET45
+        /// <summary>
+        /// Sets the static HttpContext.Current for use in unit tests.
+        /// Request URL is set specifically to evaluate httpContext.Request.Url during tests.
+        /// </summary>
+        public static HttpContext SetFakeHttpContext(IDictionary<string, string> headers = null, Func<string> remoteAddr = null)
+        {
+            string urlPath = "/SeLog.svc/EventData";
+            string urlQueryString = "eventDetail=2";
+
+            Thread.GetDomain().SetData(".appPath", string.Empty);
+            Thread.GetDomain().SetData(".appVPath", string.Empty);
+
+            var workerRequest = new SimpleWorkerRequestWithHeaders(urlPath, urlQueryString, new StringWriter(CultureInfo.InvariantCulture), headers, remoteAddr);
+
+            var context = new HttpContext(workerRequest);
+            HttpContext.Current = context;
+
+            return context;
+        }
+
+        private class SimpleWorkerRequestWithHeaders : SimpleWorkerRequest
+        {
+            private readonly IDictionary<string, string> headers;
+
+            private readonly Func<string> getRemoteAddress;
+
+            public SimpleWorkerRequestWithHeaders(string page, string query, TextWriter output, IDictionary<string, string> headers, Func<string> getRemoteAddress = null)
+                : base(page, query, output)
+            {
+                if (headers != null)
+                {
+                    this.headers = headers;
+                }
+                else
+                {
+                    this.headers = new Dictionary<string, string>();
+                }
+
+                this.getRemoteAddress = getRemoteAddress;
+            }
+
+            public override string[][] GetUnknownRequestHeaders()
+            {
+                List<string[]> result = new List<string[]>();
+
+                foreach (var header in this.headers)
+                {
+                    result.Add(new string[] { header.Key, header.Value });
+                }
+
+                var baseResult = base.GetUnknownRequestHeaders();
+                if (baseResult != null)
+                {
+                    result.AddRange(baseResult);
+                }
+
+                return result.ToArray();
+            }
+
+            public override string GetUnknownRequestHeader(string name)
+            {
+                if (this.headers.ContainsKey(name))
+                {
+                    return this.headers[name];
+                }
+
+                return base.GetUnknownRequestHeader(name);
+            }
+
+            public override string GetKnownRequestHeader(int index)
+            {
+                var name = HttpWorkerRequest.GetKnownRequestHeaderName(index);
+
+                if (this.headers.ContainsKey(name))
+                {
+                    return this.headers[name];
+                }
+
+                return base.GetKnownRequestHeader(index);
+            }
+
+            public override string GetRemoteAddress()
+            {
+                if (this.getRemoteAddress != null)
+                {
+                    return this.getRemoteAddress();
+                }
+
+                return base.GetRemoteAddress();
+            }
+        }
+#endif
+    }
+}

Src/PerformanceCollector/Perf.Shared.Tests/Perf.Shared.Tests.projitems

@@ -18,6 +18,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Filtering\FilterTests.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Filtering\Mocks\TelemetryMock.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)GlobalSuppressions.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Helpers\HttpContextHelper.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Helpers\SimpleTelemetryProcessorSpy.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Mocks\PerformanceCollectorMock.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)PerformanceCollectorEventSourceTests.cs" />

Src/PerformanceCollector/Perf.Shared.Tests/QuickPulse/QuickPulseTelemetryProcessorTests.cs

@@ -5,13 +5,14 @@
     using System.Globalization;
     using System.Linq;
     using System.Threading.Tasks;
-
+    using Microsoft.ApplicationInsights.Common.Internal;
     using Microsoft.ApplicationInsights.DataContracts;
     using Microsoft.ApplicationInsights.Extensibility;
     using Microsoft.ApplicationInsights.Extensibility.Filtering;
     using Microsoft.ApplicationInsights.Extensibility.Implementation;
     using Microsoft.ApplicationInsights.Extensibility.PerfCounterCollector.Implementation.QuickPulse;
     using Microsoft.ApplicationInsights.Extensibility.PerfCounterCollector.QuickPulse;
+    using Microsoft.ApplicationInsights.Extensibility.PerfCounterCollector.Tests.Helpers;
     using Microsoft.ApplicationInsights.Web.Helpers;
     using Microsoft.ManagementServices.RealTimeDataProcessing.QuickPulseService;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
@@ -2986,5 +2987,165 @@
             Assert.AreEqual((taskCount / 2) + 1, allBadSlowMinValue);
             Assert.AreEqual(taskCount - 1, allBadSlowMaxValue);
         }
+
+#if NET45
+        [TestMethod]
+        public void VerifyInitializationWhenDeferredIsTrue()
+        {
+            var config = new TelemetryConfiguration();
+            config.ExperimentalFeatures.Add(ExperimentalConstants.DeferRequestTrackingProperties);
+
+            var spy = new SimpleTelemetryProcessorSpy();
+            var telemetryProcessor = new QuickPulseTelemetryProcessor(spy);
+            telemetryProcessor.Initialize(config);
+
+            Assert.IsTrue(telemetryProcessor.EvaluateDisabledTrackingProperties);
+        }
+
+        [TestMethod]
+        public void VerifyInitializationWhenDeferredIsFalse()
+        {
+            var spy = new SimpleTelemetryProcessorSpy();
+            var telemetryProcessor = new QuickPulseTelemetryProcessor(spy);
+            telemetryProcessor.Initialize(new TelemetryConfiguration());
+
+            Assert.IsFalse(telemetryProcessor.EvaluateDisabledTrackingProperties);
+        }
+
+        [TestMethod]
+        public void VerifyBehaviorWhenDeferredIsTrue()
+        {
+            // SETUP CONFIG
+            var instrumentationKey = "some ikey";
+            var config = new TelemetryConfiguration()
+            {
+                InstrumentationKey = instrumentationKey
+            };
+            config.ExperimentalFeatures.Add(ExperimentalConstants.DeferRequestTrackingProperties);
+
+            // ARRANGE
+            var accumulatorManager = GetAccumulationManager();
+            var telemetryProcessor = GetQuickPulseTelemetryProcessor(accumulatorManager, config);
+
+            // ASSERT QuickPulseTelemetryProcessor was Initialized
+            Assert.IsTrue(telemetryProcessor.EvaluateDisabledTrackingProperties);
+
+            // ACT
+            var request = new RequestTelemetry()
+            {
+                Name = Guid.NewGuid().ToString(),
+                Success = true,
+                ResponseCode = "500",
+                Context = { InstrumentationKey = instrumentationKey },
+                Url = null, // THIS IS WHAT WE'RE TESTING
+            };
+
+            var httpContext = HttpContextHelper.SetFakeHttpContext(); // QuickPulseTelemetryProcessor should use the Url from the Current HttpContext.
+
+            telemetryProcessor.Process(request);
+
+            // ASSERT
+            Assert.IsFalse(accumulatorManager.CurrentDataAccumulator.GlobalDocumentQuotaReached);
+            Assert.AreEqual(1, accumulatorManager.CurrentDataAccumulator.TelemetryDocuments.Count);
+            var collectedTelemetry = accumulatorManager.CurrentDataAccumulator.TelemetryDocuments.ToArray().Reverse().ToArray();
+
+            Assert.AreEqual(TelemetryDocumentType.Request, Enum.Parse(typeof(TelemetryDocumentType), collectedTelemetry[0].DocumentType));
+            var requestTelemetryDocument = (RequestTelemetryDocument)collectedTelemetry[0];
+
+            Assert.AreEqual(request.Name, requestTelemetryDocument.Name);
+
+            // this is what we care about
+            Assert.IsNotNull(requestTelemetryDocument.Url, "request url was not set");
+            Assert.AreEqual(httpContext.Request.Url, requestTelemetryDocument.Url, "RequestTelemetryDocument should use the URL of the httpcontext");
+        }
+
+        [TestMethod]
+        public void VerifyBehaviorWhenDeferredIsFalse()
+        {
+            // SETUP CONFIG
+            var instrumentationKey = "some ikey";
+            var config = new TelemetryConfiguration()
+            {
+                InstrumentationKey = instrumentationKey
+            };
+
+            // ARRANGE
+            var accumulatorManager = GetAccumulationManager();
+            var telemetryProcessor = GetQuickPulseTelemetryProcessor(accumulatorManager, config);
+
+            // ASSERT QuickPulseTelemetryProcessor was Initialized
+            Assert.IsFalse(telemetryProcessor.EvaluateDisabledTrackingProperties);
+
+            // ACT
+            var request = new RequestTelemetry()
+            {
+                Name = Guid.NewGuid().ToString(),
+                Success = true,
+                ResponseCode = "500",
+                Context = { InstrumentationKey = instrumentationKey },
+                Url = null, // THIS IS WHAT WE'RE TESTING
+            };
+
+            telemetryProcessor.Process(request);
+
+            // ASSERT
+            Assert.IsFalse(accumulatorManager.CurrentDataAccumulator.GlobalDocumentQuotaReached);
+            Assert.AreEqual(1, accumulatorManager.CurrentDataAccumulator.TelemetryDocuments.Count);
+            var collectedTelemetry = accumulatorManager.CurrentDataAccumulator.TelemetryDocuments.ToArray().Reverse().ToArray();
+
+            Assert.AreEqual(TelemetryDocumentType.Request, Enum.Parse(typeof(TelemetryDocumentType), collectedTelemetry[0].DocumentType));
+            var requestTelemetryDocument = (RequestTelemetryDocument)collectedTelemetry[0];
+
+            Assert.AreEqual(request.Name, requestTelemetryDocument.Name);
+
+            // this is what we care about
+            Assert.IsNull(requestTelemetryDocument.Url, "request url was not set");
+        }
+#endif
+
+        private static QuickPulseDataAccumulatorManager GetAccumulationManager()
+        {
+            var requestsDocumentStreamInfo = new DocumentStreamInfo()
+            {
+                Id = "StreamRequests",
+                DocumentFilterGroups =
+                    new[]
+                    {
+                        // TODO: SHOULD GET THESE FILTERS FROM THE PARAMATER SO OTHER TESTS CAN SHARE THIS METHOD
+                        new DocumentFilterConjunctionGroupInfo()
+                        {
+                            TelemetryType = TelemetryType.Request,
+                            Filters =
+                                new FilterConjunctionGroupInfo
+                                {
+                                    Filters = new[] { new FilterInfo { FieldName = "Success", Predicate = Predicate.Equal, Comparand = "0" } }
+                                }
+                        },
+                    }
+            };
+
+            var collectionConfigurationInfo = new CollectionConfigurationInfo()
+            {
+                DocumentStreams = new[] { requestsDocumentStreamInfo },
+            };
+            var collectionConfiguration = new CollectionConfiguration(collectionConfigurationInfo, out errors, new ClockMock());
+            var accumulatorManager = new QuickPulseDataAccumulatorManager(collectionConfiguration);
+
+            return accumulatorManager;
+        }
+
+        private static QuickPulseTelemetryProcessor GetQuickPulseTelemetryProcessor(QuickPulseDataAccumulatorManager accumulatorManager, TelemetryConfiguration configuration)
+        {
+            var spy = new SimpleTelemetryProcessorSpy();
+            var telemetryProcessor = new QuickPulseTelemetryProcessor(spy);
+            telemetryProcessor.Initialize(configuration);
+
+            ((IQuickPulseTelemetryProcessor)telemetryProcessor).StartCollection(
+                accumulatorManager,
+                new Uri("http://microsoft.com"),
+                configuration);
+
+            return telemetryProcessor;
+        }
     }
 }

Src/PerformanceCollector/Perf.Shared/QuickPulseTelemetryProcessor.cs

@@ -9,9 +9,11 @@
 
     using Microsoft.ApplicationInsights.Channel;
     using Microsoft.ApplicationInsights.Common;
+    using Microsoft.ApplicationInsights.Common.Internal;
     using Microsoft.ApplicationInsights.DataContracts;
     using Microsoft.ApplicationInsights.Extensibility.Filtering;
     using Microsoft.ApplicationInsights.Extensibility.Implementation;
+    using Microsoft.ApplicationInsights.Extensibility.Implementation.Experimental;
     using Microsoft.ApplicationInsights.Extensibility.Implementation.Tracing;
     using Microsoft.ApplicationInsights.Extensibility.PerfCounterCollector.Implementation.QuickPulse;
     using Microsoft.ApplicationInsights.Extensibility.PerfCounterCollector.Implementation.QuickPulse.Helpers;
@@ -114,6 +116,8 @@
             this telemetry processor will only collect for whichever instrumentation key is specified by the module in StartCollection call.
             */
 
+            this.EvaluateDisabledTrackingProperties = configuration.EvaluateExperimentalFeature(ExperimentalConstants.DeferRequestTrackingProperties);
+
             this.Register();
         }
 
@@ -194,7 +198,7 @@
             {
                 try
                 {
-                    // some of the requestTelemetry properties might be deffered by using RequestTrackingTelemetryModule.DisableTrackingProperties.
+                    // some of the requestTelemetry properties might be deferred by using RequestTrackingTelemetryModule.DisableTrackingProperties.
                     // evaluate them now
                     // note: RequestTrackingUtilities.UpdateRequestTelemetryFromRequest is not used here, since not all fields need to be populated
                     var request = System.Web.HttpContext.Current?.Request;
@@ -217,7 +221,7 @@
                 Success = requestTelemetry.Success,
                 Duration = requestTelemetry.Duration,
                 ResponseCode = requestTelemetry.ResponseCode,
-                Url = requestTelemetry.Url,
+                Url = url,
                 Properties = GetProperties(requestTelemetry),
             };
 

Src/PerformanceCollector/PerformanceCollector/Perf.csproj

@@ -27,7 +27,7 @@
     <PackageReference Include="StyleCop.Analyzers" Version="1.1.118">
       <PrivateAssets>All</PrivateAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.CodeAnalysis.FxCopAnalyzers" Version="2.9.2" >
+    <PackageReference Include="Microsoft.CodeAnalysis.FxCopAnalyzers" Version="2.9.2">
       <PrivateAssets>All</PrivateAssets>
     </PackageReference>
     <PackageReference Include="MicroBuild.Core" Version="0.3.0">

Src/Web/Web.Net45.Tests/Web.Net45.Tests.csproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="15.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildProjectDirectory), 'Test.props'))\Test.props" />
   <PropertyGroup>
@@ -144,4 +144,4 @@
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory), 'Common.targets'))\Common.targets" />
   <Import Project="..\..\TestFramework\Shared\TestFramework.Shared.projitems" Label="Shared" />
-</Project>
+</Project>

Src/Web/Web.Net45.Tests/packages.config

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <packages>
   <package id="Castle.Core" version="4.4.0" targetFramework="net451" />
   <package id="Microsoft.ApplicationInsights" version="2.11.0-beta1" targetFramework="net451" />
@@ -24,4 +24,4 @@
   <package id="xunit.core" version="2.1.0" targetFramework="net451" />
   <package id="xunit.extensibility.core" version="2.1.0" targetFramework="net451" />
   <package id="xunit.extensibility.execution" version="2.1.0" targetFramework="net451" />
-</packages>
+</packages>

Src/Web/Web.Shared.Net.Tests/RequestTrackingTelemetryModuleTest.cs

@@ -10,17 +10,20 @@
 
     using Microsoft.ApplicationInsights.Channel;
     using Microsoft.ApplicationInsights.Common;
+    using Microsoft.ApplicationInsights.Common.Internal;
     using Microsoft.ApplicationInsights.DataContracts;
     using Microsoft.ApplicationInsights.Extensibility;
     using Microsoft.ApplicationInsights.Extensibility.Implementation;
     using Microsoft.ApplicationInsights.Extensibility.W3C;
     using Microsoft.ApplicationInsights.TestFramework;
+    using Microsoft.ApplicationInsights.Web.Extensibility.Implementation;
     using Microsoft.ApplicationInsights.Web.Helpers;
     using Microsoft.ApplicationInsights.Web.Implementation;
     using Microsoft.ApplicationInsights.Web.TestFramework;
     using Microsoft.VisualStudio.TestTools.UnitTesting;
-
+    using Xunit.Sdk;
     using Assert = Xunit.Assert;
+    using MsAssert = Microsoft.VisualStudio.TestTools.UnitTesting.Assert;
 
     /// <summary>
     /// Platform independent tests for RequestTrackingTelemetryModule.
@@ -393,9 +396,9 @@
             var config = TelemetryConfiguration.CreateDefault();
             config.InstrumentationKey = TestInstrumentationKey1;
             config.ApplicationIdProvider = new MockApplicationIdProvider(TestInstrumentationKey1, TestApplicationId1);
+            config.ExperimentalFeatures.Add("DeferRequestTrackingProperties");
             
             var module = this.RequestTrackingTelemetryModuleFactory(null /*use default*/);
-            module.DisableTrackingProperties = true;
             
             // ACT
             module.Initialize(config);
@@ -478,6 +481,53 @@
             Assert.True(intermediateRequest.Properties.ContainsKey("AI internal"));
         }
 
+        [TestMethod]
+        public void VerifyBehaviorWhenDeferredIsFalse()
+        {
+            var config = this.CreateDefaultConfig(HttpModuleHelper.GetFakeHttpContext());
+            var context = HttpModuleHelper.GetFakeHttpContext();
+
+            // Create, Initialize, and Validate RequestTrackingTelemetryModule
+            var module = this.RequestTrackingTelemetryModuleFactory(config);
+            MsAssert.IsFalse(module.DisableTrackingProperties, $"{nameof(module.DisableTrackingProperties)} should be False by default.");
+
+            // Validate Telemetry Processor Chain
+            MsAssert.IsFalse(config.DefaultTelemetrySink.TelemetryProcessors.Any(x => x is PostSamplingTelemetryProcessor));
+
+            // Run test to generate requestTelemetry
+            module.OnBeginRequest(context);
+            module.OnEndRequest(context);
+            var requestTelemetry = context.GetRequestTelemetry();
+
+            // Validate requestTelemetry
+            MsAssert.IsNotNull(requestTelemetry, "TEST ERROR: Failed to create requestTelemetry.");
+            MsAssert.IsNotNull(requestTelemetry.Url);
+        }
+
+        [TestMethod]
+        public void VerifyBehaviorWhenDeferredIsTrue()
+        {
+            var context = HttpModuleHelper.GetFakeHttpContext();
+            var config = new TelemetryConfiguration();
+            config.ExperimentalFeatures.Add(ExperimentalConstants.DeferRequestTrackingProperties);
+
+            // Create and Validate RequestTrackingTelemetryModule
+            var module = this.RequestTrackingTelemetryModuleFactory(config);
+            MsAssert.IsTrue(module.DisableTrackingProperties, "TEST ERROR: Module was not initialized with custom config.");
+
+            // Validate Telemetry Processor Chain
+            MsAssert.IsTrue(config.DefaultTelemetrySink.TelemetryProcessors.Any(x => x is PostSamplingTelemetryProcessor), "Module should inject PostSamplingTelemetryProcessor");
+
+            // Run test to generate requestTelemetry
+            module.OnBeginRequest(context);
+            module.OnEndRequest(context);
+            var requestTelemetry = context.GetRequestTelemetry();
+
+            // Validate requestTelemetry
+            MsAssert.IsNotNull(requestTelemetry, "TEST ERROR: Failed to create requestTelemetry.");
+            MsAssert.IsNotNull(requestTelemetry.Url); // set by PostSamplingTelemetryProcessor
+        }
+
         private TelemetryConfiguration CreateDefaultConfig(HttpContext fakeContext, string rootIdHeaderName = null, string parentIdHeaderName = null, string instrumentationKey = null)
         {
             var telemetryChannel = new StubTelemetryChannel()

Src/Web/Web.Shared.Net/RequestTrackingTelemetryModule.cs

@@ -11,6 +11,7 @@
     using Microsoft.ApplicationInsights.DataContracts;
     using Microsoft.ApplicationInsights.Extensibility;
     using Microsoft.ApplicationInsights.Extensibility.Implementation;
+    using Microsoft.ApplicationInsights.Extensibility.Implementation.Experimental;
     using Microsoft.ApplicationInsights.Extensibility.Implementation.Tracing;
     using Microsoft.ApplicationInsights.Web.Extensibility.Implementation;
     using Microsoft.ApplicationInsights.Web.Implementation;
@@ -265,6 +266,13 @@
             this.telemetryClient = new TelemetryClient(configuration);
             this.telemetryClient.Context.GetInternalContext().SdkVersion = SdkVersionUtils.GetSdkVersion("web:");
 
+            this.DisableTrackingProperties = configuration.EvaluateExperimentalFeature(Microsoft.ApplicationInsights.Common.Internal.ExperimentalConstants.DeferRequestTrackingProperties);
+            if (this.DisableTrackingProperties)
+            {
+                configuration.DefaultTelemetrySink.TelemetryProcessorChainBuilder.Use(next => new PostSamplingTelemetryProcessor(next));
+                configuration.DefaultTelemetrySink.TelemetryProcessorChainBuilder.Build();
+            }
+
             // Headers will be read-only in a classic iis pipeline
             // Exception System.PlatformNotSupportedException: This operation requires IIS integrated pipeline mode.
             if (HttpRuntime.UsingIntegratedPipeline && this.EnableChildRequestTrackingSuppression)

Src/Web/Web/Web.csproj

@@ -26,7 +26,7 @@
     <PackageReference Include="StyleCop.Analyzers" Version="1.1.118">
       <PrivateAssets>All</PrivateAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.CodeAnalysis.FxCopAnalyzers" Version="2.9.2" >
+    <PackageReference Include="Microsoft.CodeAnalysis.FxCopAnalyzers" Version="2.9.2">
       <PrivateAssets>All</PrivateAssets>
     </PackageReference>
     <PackageReference Include="MicroBuild.Core" Version="0.3.0">

Src/WindowsServer/WindowsServer.Net45.Tests/WindowsServer.Net45.Tests.csproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="15.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildProjectDirectory), 'Test.props'))\Test.props" />
   <PropertyGroup>
@@ -106,4 +106,4 @@
   <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildThisFileDirectory), 'Common.targets'))\Common.targets" />
   <Import Project="..\..\TestFramework\Shared\TestFramework.Shared.projitems" Label="Shared" />
   <Import Project="..\WindowsServer.Shared.Tests\WindowsServer.Shared.Tests.projitems" Label="Shared" />
-</Project>
+</Project>

Src/WindowsServer/WindowsServer.Net45.Tests/packages.config

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <packages>
   <package id="Microsoft.ApplicationInsights" version="2.11.0-beta1" targetFramework="net45" />
   <package id="StyleCop.Analyzers" version="1.0.2" targetFramework="net45" developmentDependency="true" />
@@ -9,4 +9,4 @@
   <package id="xunit.core" version="2.1.0" targetFramework="net45" />
   <package id="xunit.extensibility.core" version="2.1.0" targetFramework="net45" />
   <package id="xunit.extensibility.execution" version="2.1.0" targetFramework="net45" />
-</packages>
+</packages>