remove correlationIdLookupHelper.

src/Microsoft.ApplicationInsights.AspNetCore/DiagnosticListeners/Implementation/HostingDiagnosticListener.cs

@@ -9,6 +9,7 @@
     using Microsoft.ApplicationInsights.AspNetCore.Common;
     using Microsoft.ApplicationInsights.AspNetCore.Extensions;
     using Microsoft.ApplicationInsights.DataContracts;
+    using Microsoft.ApplicationInsights.Extensibility;
     using Microsoft.ApplicationInsights.Extensibility.Implementation;
     using Microsoft.AspNetCore.Hosting;
     using Microsoft.AspNetCore.Http;
@@ -28,20 +29,19 @@ internal class HostingDiagnosticListener : IApplicationInsightDiagnosticListener
         public static bool IsAspNetCore20 = typeof(WebHostBuilder).GetTypeInfo().Assembly.GetName().Version.Major >= 2;
 
         private readonly TelemetryClient client;
-        private readonly ICorrelationIdLookupHelper correlationIdLookupHelper;
-        private readonly string sdkVersion;
+        private readonly IApplicationIdProvider applicationIdProvider;
+        private readonly string sdkVersion = SdkVersionUtils.GetVersion();
         private const string ActivityCreatedByHostingDiagnosticListener = "ActivityCreatedByHostingDiagnosticListener";
 
         /// <summary>
         /// Initializes a new instance of the <see cref="T:HostingDiagnosticListener"/> class.
         /// </summary>
         /// <param name="client"><see cref="TelemetryClient"/> to post traces to.</param>
-        /// <param name="correlationIdLookupHelper">A store for correlation ids that we don't have to query it everytime.</param>
-        public HostingDiagnosticListener(TelemetryClient client, ICorrelationIdLookupHelper correlationIdLookupHelper)
+        /// <param name="applicationIdProvider">Nullable Provider for resolving application Id to be used by Correlation.</param>
+        public HostingDiagnosticListener(TelemetryClient client, IApplicationIdProvider applicationIdProvider = null)
         {
-            this.client = client;
-            this.correlationIdLookupHelper = correlationIdLookupHelper;
-            this.sdkVersion = SdkVersionUtils.VersionPrefix + SdkVersionUtils.GetAssemblyVersion();
+            this.client = client ?? throw new ArgumentNullException(nameof(client));
+            this.applicationIdProvider = applicationIdProvider;
         }
 
         /// <inheritdoc/>
@@ -236,10 +236,10 @@ private void SetAppIdInResponseHeader(HttpContext httpContext, RequestTelemetry
                 !string.IsNullOrEmpty(requestTelemetry.Context.InstrumentationKey) &&
                 (!responseHeaders.ContainsKey(RequestResponseHeaders.RequestContextHeader) || HttpHeadersUtilities.ContainsRequestContextKeyValue(responseHeaders, RequestResponseHeaders.RequestContextTargetKey)))
             {
-                string correlationId = null;
-                if (this.correlationIdLookupHelper.TryGetXComponentCorrelationId(requestTelemetry.Context.InstrumentationKey, out correlationId))
+                string applicationId = null;
+                if (this.applicationIdProvider?.TryGetApplicationId(requestTelemetry.Context.InstrumentationKey, out applicationId) ?? false)
                 {
-                    HttpHeadersUtilities.SetRequestContextKeyValue(responseHeaders, RequestResponseHeaders.RequestContextTargetKey, correlationId);
+                    HttpHeadersUtilities.SetRequestContextKeyValue(responseHeaders, RequestResponseHeaders.RequestContextTargetKey, applicationId);
                 }
             }
         }

src/Microsoft.ApplicationInsights.AspNetCore/ExceptionTrackingMiddleware.cs

@@ -20,7 +20,7 @@ public ExceptionTrackingMiddleware(RequestDelegate next, TelemetryClient client)
         {
             this.next = next;
             this.telemetryClient = client;
-            this.sdkVersion = SdkVersionUtils.VersionPrefix + SdkVersionUtils.GetAssemblyVersion();
+            this.sdkVersion = SdkVersionUtils.GetVersion();
         }
 
         public async Task Invoke(HttpContext httpContext)

src/Microsoft.ApplicationInsights.AspNetCore/Extensions/ApplicationInsightsExtensions.cs

@@ -15,6 +15,7 @@ namespace Microsoft.Extensions.DependencyInjection
     using Microsoft.ApplicationInsights.Channel;
     using Microsoft.ApplicationInsights.DependencyCollector;
     using Microsoft.ApplicationInsights.Extensibility;
+    using Microsoft.ApplicationInsights.Extensibility.Implementation.ApplicationId;
     using Microsoft.ApplicationInsights.Extensibility.PerfCounterCollector.QuickPulse;
     using Microsoft.ApplicationInsights.WindowsServer;    
     using Microsoft.ApplicationInsights.WindowsServer.TelemetryChannel;
@@ -168,7 +169,7 @@ public static IServiceCollection AddApplicationInsightsTelemetry(this IServiceCo
                 services.AddSingleton<ITelemetryModule, QuickPulseTelemetryModule>();
                 services.AddSingleton<TelemetryConfiguration>(provider => provider.GetService<IOptions<TelemetryConfiguration>>().Value);
 
-                services.AddSingleton<ICorrelationIdLookupHelper>(provider => new CorrelationIdLookupHelper(() => provider.GetService<IOptions<TelemetryConfiguration>>().Value));
+                services.TryAddSingleton<IApplicationIdProvider, ApplicationInsightsApplicationIdProvider>();
 
                 services.AddSingleton<TelemetryClient>();
 

src/Microsoft.ApplicationInsights.AspNetCore/Implementation/TelemetryConfigurationOptionsSetup.cs

@@ -26,6 +26,7 @@ internal class TelemetryConfigurationOptionsSetup : IConfigureOptions<TelemetryC
         private readonly ITelemetryChannel telemetryChannel;
         private readonly IEnumerable<ITelemetryProcessorFactory> telemetryProcessorFactories;
         private readonly IEnumerable<ITelemetryModuleConfigurator> telemetryModuleConfigurators;
+        private readonly IApplicationIdProvider applicationIdProvider;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="T:TelemetryConfigurationOptionsSetup"/> class.
@@ -44,6 +45,7 @@ public TelemetryConfigurationOptionsSetup(
             this.telemetryProcessorFactories = telemetryProcessorFactories;
             this.telemetryModuleConfigurators = telemetryModuleConfigurators;
             this.telemetryChannel = serviceProvider.GetService<ITelemetryChannel>();
+            this.applicationIdProvider = serviceProvider.GetService<IApplicationIdProvider>();
         }
 
         /// <inheritdoc />
@@ -116,6 +118,9 @@ public void Configure(TelemetryConfiguration configuration)
                     module.Initialize(configuration);
                 }
             }
+
+            // Microsoft.ApplicationInsights.DependencyCollector.DependencyTrackingTelemetryModule depends on this nullable configuration to support Correlation. 
+            configuration.ApplicationIdProvider = this.applicationIdProvider;
         }
 
         private void AddQuickPulse(TelemetryConfiguration configuration)

src/Microsoft.ApplicationInsights.AspNetCore/Logging/Implementation/ApplicationInsightsLogger.cs

@@ -18,7 +18,7 @@ internal class ApplicationInsightsLogger : ILogger
         private readonly TelemetryClient telemetryClient;
         private readonly Func<string, LogLevel, bool> filter;
         private readonly ApplicationInsightsLoggerOptions options;
-        private readonly string sdkVersion;
+        private readonly string sdkVersion = SdkVersionUtils.GetVersion();
 
         /// <summary>
         /// Creates a new instance of <see cref="ApplicationInsightsLogger"/>
@@ -29,7 +29,6 @@ public ApplicationInsightsLogger(string name, TelemetryClient telemetryClient, F
             this.telemetryClient = telemetryClient;
             this.filter = filter;
             this.options = options;
-            this.sdkVersion = SdkVersionUtils.VersionPrefix + SdkVersionUtils.GetAssemblyVersion();
         }
 
         /// <inheritdoc />

src/Microsoft.ApplicationInsights.AspNetCore/Microsoft.ApplicationInsights.AspNetCore.csproj

@@ -4,7 +4,7 @@
     <Description>Application Insights for ASP.NET Core web applications. See https://azure.microsoft.com/documentation/articles/app-insights-asp-net-five/ for more information. Privacy statement: https://go.microsoft.com/fwlink/?LinkId=512156</Description>
     <Copyright>Copyright © Microsoft. All Rights Reserved.</Copyright>
     <AssemblyTitle>Application Insights for ASP.NET Core Web Applications</AssemblyTitle>
-    <VersionPrefix>2.2.1</VersionPrefix>
+    <VersionPrefix>2.3.0-beta1</VersionPrefix>
     <Authors>Microsoft</Authors>
     <TargetFrameworks>net451;net46;netstandard1.6</TargetFrameworks>
     <TargetFrameworks Condition=" '$(OS)' != 'Windows_NT' ">netstandard1.6</TargetFrameworks>
@@ -72,17 +72,15 @@
     <PackageReference Include="System.Threading.Tasks.Analyzers" Version="1.2.0-beta2">
       <PrivateAssets>All</PrivateAssets>
     </PackageReference>
-    <PackageReference Include="Microsoft.ApplicationInsights" Version="2.6.0-beta2" />
-    <PackageReference Include="Microsoft.ApplicationInsights.DependencyCollector" Version="2.6.0-beta2-build14769" />
-    <PackageReference Include="Microsoft.ApplicationInsights.PerfCounterCollector" Version="2.6.0-beta2-build14769" />
-    <PackageReference Include="Microsoft.ApplicationInsights.WindowsServer" Version="2.6.0-beta2-build14769" />
-    <PackageReference Include="Microsoft.ApplicationInsights.WindowsServer.TelemetryChannel" Version="2.6.0-beta2" />
+    <PackageReference Include="Microsoft.ApplicationInsights" Version="2.6.0-beta3" />
+    <PackageReference Include="Microsoft.ApplicationInsights.DependencyCollector" Version="2.6.0-beta3" />
+    <PackageReference Include="Microsoft.ApplicationInsights.PerfCounterCollector" Version="2.6.0-beta3" />
+    <PackageReference Include="Microsoft.ApplicationInsights.WindowsServer" Version="2.6.0-beta3" />
+    <PackageReference Include="Microsoft.ApplicationInsights.WindowsServer.TelemetryChannel" Version="2.6.0-beta3" />
   </ItemGroup>
 
   <ItemGroup Condition=" '$(TargetFramework)' == 'net451' OR '$(TargetFramework)' == 'net46' ">
     <PackageReference Include="System.Net.Http" Version="4.3.1" />
-    <PackageReference Include="Microsoft.ApplicationInsights.PerfCounterCollector" Version="2.6.0-beta2-build14769" />
-    <PackageReference Include="Microsoft.ApplicationInsights.WindowsServer.TelemetryChannel" Version="2.6.0-beta2" />
     <Reference Include="System" />
     <Reference Include="Microsoft.CSharp" />
   </ItemGroup>

src/Microsoft.ApplicationInsights.AspNetCore/SdkVersionUtils.cs

@@ -11,7 +11,15 @@ internal class SdkVersionUtils
         public const string VersionPrefix = "aspnet5c:";
 #endif
 
-        internal static string GetAssemblyVersion()
+        /// <summary>
+        /// Get the Assembly Version with SDK prefix.
+        /// </summary>
+        internal static string GetVersion()
+        {
+            return VersionPrefix + GetAssemblyVersion();
+        }
+
+        private static string GetAssemblyVersion()
         {
             return typeof(SdkVersionUtils).GetTypeInfo().Assembly.GetCustomAttributes<AssemblyInformationalVersionAttribute>()
                       .First()

src/Microsoft.ApplicationInsights.AspNetCore/TelemetryInitializers/OperationCorrelationTelemetryInitializer.cs

@@ -1,35 +1,28 @@
 namespace Microsoft.ApplicationInsights.AspNetCore.TelemetryInitializers
 {
     using System;
-    using System.Net.Http.Headers;
     using Microsoft.ApplicationInsights.AspNetCore.Common;
     using Microsoft.ApplicationInsights.AspNetCore.DiagnosticListeners;
     using Microsoft.ApplicationInsights.Channel;
     using Microsoft.ApplicationInsights.DataContracts;
-    using Microsoft.ApplicationInsights.Extensibility.Implementation;
+    using Microsoft.ApplicationInsights.Extensibility;
     using Microsoft.AspNetCore.Http;
-    using Microsoft.Extensions.Primitives;
 
     /// <summary>
     /// A telemetry initializer that will set the correlation context for all telemetry items in web application.
     /// </summary>
     internal class OperationCorrelationTelemetryInitializer : TelemetryInitializerBase
     {
-        private ICorrelationIdLookupHelper correlationIdLookupHelper = null;
+        private readonly IApplicationIdProvider applicationIdProvider;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="OperationCorrelationTelemetryInitializer"/> class.
         /// </summary>
         /// <param name="httpContextAccessor">Accessor for retrieving the current HTTP context.</param>
-        /// <param name="correlationIdLookupHelper">A store for correlation ids that we don't have to query it everytime.</param>
-        public OperationCorrelationTelemetryInitializer(
-            IHttpContextAccessor httpContextAccessor, ICorrelationIdLookupHelper correlationIdLookupHelper) : base(httpContextAccessor)
+        /// <param name="applicationIdProvider">Nullable Provider for resolving application Id to be used by Correlation.</param>
+        public OperationCorrelationTelemetryInitializer(IHttpContextAccessor httpContextAccessor, IApplicationIdProvider applicationIdProvider = null) : base(httpContextAccessor)
         {
-            if (correlationIdLookupHelper == null)
-            {
-                throw new ArgumentNullException(nameof(correlationIdLookupHelper));
-            }
-            this.correlationIdLookupHelper = correlationIdLookupHelper;
+            this.applicationIdProvider = applicationIdProvider;
         }
 
         /// <summary>
@@ -38,17 +31,14 @@ public OperationCorrelationTelemetryInitializer(
         /// <param name="platformContext">Http context</param>
         /// <param name="requestTelemetry">Request telemetry object associated with the current request.</param>
         /// <param name="telemetry">Telemetry item to initialize.</param>
-        protected override void OnInitializeTelemetry(
-            HttpContext platformContext,
-            RequestTelemetry requestTelemetry,
-            ITelemetry telemetry)
+        protected override void OnInitializeTelemetry(HttpContext platformContext, RequestTelemetry requestTelemetry, ITelemetry telemetry)
         {
             HttpRequest currentRequest = platformContext.Request;
             if (currentRequest?.Headers != null && string.IsNullOrEmpty(requestTelemetry.Source))
             {
-                string headerCorrelationId = HttpHeadersUtilities.GetRequestContextKeyValue(currentRequest.Headers, RequestResponseHeaders.RequestContextSourceKey);                
+                string headerCorrelationId = HttpHeadersUtilities.GetRequestContextKeyValue(currentRequest.Headers, RequestResponseHeaders.RequestContextSourceKey);
 
-                string appCorrelationId = null;
+                string applicationId = null;
                 // If the source header is present on the incoming request, and it is an external component (not the same ikey as the one used by the current component), populate the source field.
                 if (!string.IsNullOrEmpty(headerCorrelationId))
                 {
@@ -57,8 +47,8 @@ protected override void OnInitializeTelemetry(
                     {
                         requestTelemetry.Source = headerCorrelationId;
                     }
-                    else if (this.correlationIdLookupHelper.TryGetXComponentCorrelationId(requestTelemetry.Context.InstrumentationKey, out appCorrelationId) &&
-                        appCorrelationId != headerCorrelationId)
+                    else if ((this.applicationIdProvider?.TryGetApplicationId(requestTelemetry.Context.InstrumentationKey, out applicationId) ?? false)
+                        && applicationId != headerCorrelationId)
                     {
                         requestTelemetry.Source = headerCorrelationId;
                     }