Support Asp.Net Framework (#61)

* Add SkyWalking.AspNet project

* Support .NET 4.5

* Support Asp.Net Framework

* Add Sample.AspNet project

* Fix CI

* Close grpc connection when application pool recycles

sample/SkyWalking.Sample.AspNet/App_Start/RouteConfig.cs

+using System.Web.Mvc;
+using System.Web.Routing;
+
+namespace SkyWalking.Sample.AspNet
+{
+    public class RouteConfig
+    {
+        public static void RegisterRoutes(RouteCollection routes)
+        {
+            routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
+
+            routes.MapRoute(
+                "Default",
+                "{controller}/{action}/{id}",
+                new {controller = "Home", action = "Index", id = UrlParameter.Optional}
+            );
+        }
+    }
+}
\ No newline at end of file

sample/SkyWalking.Sample.AspNet/App_Start/WebApiConfig.cs

+using System.Web.Http;
+
+namespace SkyWalking.Sample.AspNet
+{
+    public static class WebApiConfig
+    {
+        public static void Register(HttpConfiguration config)
+        {
+            // Web API configuration and services
+
+            // Web API routes
+            config.MapHttpAttributeRoutes();
+
+            config.Routes.MapHttpRoute(
+                "DefaultApi",
+                "api/{controller}/{id}",
+                new {id = RouteParameter.Optional}
+            );
+        }
+    }
+}
\ No newline at end of file

sample/SkyWalking.Sample.AspNet/Controllers/ValuesController.cs

+using System.Net.Http;
+using System.Threading.Tasks;
+using System.Web.Http;
+using SkyWalking.AspNet;
+
+namespace SkyWalking.Sample.AspNet.Controllers
+{
+    public class ValuesController : ApiController
+    {
+        public async Task<IHttpActionResult> Get()
+        {
+            var httpClient = new HttpClient(new HttpTracingHandler());
+            var values = await httpClient.GetStringAsync("http://localhost:5002/api/values");
+            return Json(values);
+        }
+    }
+}
\ No newline at end of file

sample/SkyWalking.Sample.AspNet/Global.asax

+<%@ Application Inherits="SkyWalking.Sample.AspNet.Global" %>

sample/SkyWalking.Sample.AspNet/Global.asax.cs

+using System.Web;
+using System.Web.Mvc;
+using System.Web.Routing;
+using System.Web.Http;
+
+namespace SkyWalking.Sample.AspNet
+{
+    public class Global : HttpApplication
+    {
+        protected void Application_Start()
+        {
+            AreaRegistration.RegisterAllAreas();
+            GlobalConfiguration.Configure(WebApiConfig.Register);
+            RouteConfig.RegisterRoutes(RouteTable.Routes);
+        }
+    }
+}
\ No newline at end of file

sample/SkyWalking.Sample.AspNet/Properties/AssemblyInfo.cs

+using System.Reflection;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+
+// General Information about an assembly is controlled through the following 
+// set of attributes. Change these attribute values to modify the information
+// associated with an assembly.
+[assembly: AssemblyTitle("SkyWalking.Sample.AspNet")]
+[assembly: AssemblyDescription("")]
+[assembly: AssemblyConfiguration("")]
+[assembly: AssemblyCompany("")]
+[assembly: AssemblyProduct("SkyWalking.Sample.AspNet")]
+[assembly: AssemblyCopyright("Copyright ©  2018")]
+[assembly: AssemblyTrademark("")]
+[assembly: AssemblyCulture("")]
+
+// Setting ComVisible to false makes the types in this assembly not visible 
+// to COM components.  If you need to access a type in this assembly from 
+// COM, set the ComVisible attribute to true on that type.
+[assembly: ComVisible(false)]
+
+// The following GUID is for the ID of the typelib if this project is exposed to COM
+[assembly: Guid("C3649845-E458-448D-B97D-C7E231E1D040")]
+
+// Version information for an assembly consists of the following four values:
+//
+//      Major Version
+//      Minor Version 
+//      Build Number
+//      Revision
+//
+// You can specify all the values or you can default the Build and Revision Numbers 
+// by using the '*' as shown below:
+// [assembly: AssemblyVersion("1.0.*")]
+[assembly: AssemblyVersion("1.0.0.0")]
+[assembly: AssemblyFileVersion("1.0.0.0")]
\ No newline at end of file

sample/SkyWalking.Sample.AspNet/SkyWalking.Sample.AspNet.csproj

+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
+  <PropertyGroup>
+    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
+    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
+    <ProjectGuid>{C3649845-E458-448D-B97D-C7E231E1D040}</ProjectGuid>
+    <ProjectTypeGuids>{349C5851-65DF-11DA-9384-00065B846F21};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
+    <OutputType>Library</OutputType>
+    <AppDesignerFolder>Properties</AppDesignerFolder>
+    <RootNamespace>SkyWalking.Sample.AspNet</RootNamespace>
+    <AssemblyName>SkyWalking.Sample.AspNet</AssemblyName>
+    <TargetFrameworkVersion>v4.5</TargetFrameworkVersion>
+    <FileAlignment>512</FileAlignment>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
+    <PlatformTarget>AnyCPU</PlatformTarget>
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>full</DebugType>
+    <Optimize>false</Optimize>
+    <OutputPath>bin\</OutputPath>
+    <DefineConstants>DEBUG;TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
+    <PlatformTarget>AnyCPU</PlatformTarget>
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\</OutputPath>
+    <DefineConstants>TRACE</DefineConstants>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+  </PropertyGroup>
+  <ItemGroup>
+    <Reference Include="Microsoft.CSharp" />
+    <Reference Include="Microsoft.Web.Infrastructure, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
+      <HintPath>../..\packages\Microsoft.Web.Infrastructure.1.0.0.0\lib\net40\Microsoft.Web.Infrastructure.dll</HintPath>
+    </Reference>
+    <Reference Include="Newtonsoft.Json, Version=6.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed">
+      <HintPath>../..\packages\Newtonsoft.Json.6.0.4\lib\net45\Newtonsoft.Json.dll</HintPath>
+    </Reference>
+    <Reference Include="System" />
+    <Reference Include="System.Core" />
+    <Reference Include="System.Data" />
+    <Reference Include="System.Net.Http" />
+    <Reference Include="System.Net.Http.Formatting, Version=5.2.3.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
+      <HintPath>../..\packages\Microsoft.AspNet.WebApi.Client.5.2.3\lib\net45\System.Net.Http.Formatting.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Web" />
+    <Reference Include="System.Web.Http, Version=5.2.3.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
+      <HintPath>../..\packages\Microsoft.AspNet.WebApi.Core.5.2.3\lib\net45\System.Web.Http.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Web.Http.WebHost, Version=5.2.3.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
+      <HintPath>../..\packages\Microsoft.AspNet.WebApi.WebHost.5.2.3\lib\net45\System.Web.Http.WebHost.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Web.Services" />
+    <Reference Include="System.Web.Routing" />
+    <Reference Include="System.Web.Extensions" />
+    <Reference Include="System.Web.Abstractions" />
+    <Reference Include="System.Web.DynamicData" />
+    <Reference Include="System.Web.Helpers, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
+      <HintPath>../..\packages\Microsoft.AspNet.WebPages.3.2.3\lib\net45\System.Web.Helpers.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Web.Mvc, Version=5.2.3.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
+      <HintPath>../..\packages\Microsoft.AspNet.Mvc.5.2.3\lib\net45\System.Web.Mvc.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Web.Razor, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
+      <HintPath>../..\packages\Microsoft.AspNet.Razor.3.2.3\lib\net45\System.Web.Razor.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Web.WebPages, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
+      <HintPath>../..\packages\Microsoft.AspNet.WebPages.3.2.3\lib\net45\System.Web.WebPages.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Web.WebPages.Deployment, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
+      <HintPath>../..\packages\Microsoft.AspNet.WebPages.3.2.3\lib\net45\System.Web.WebPages.Deployment.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Web.WebPages.Razor, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
+      <HintPath>../..\packages\Microsoft.AspNet.WebPages.3.2.3\lib\net45\System.Web.WebPages.Razor.dll</HintPath>
+    </Reference>
+    <Reference Include="System.Xml" />
+  </ItemGroup>
+  <ItemGroup>
+    <Compile Include="App_Start\RouteConfig.cs" />
+    <Compile Include="App_Start\WebApiConfig.cs" />
+    <Compile Include="Controllers\ValuesController.cs" />
+    <Compile Include="Global.asax.cs" />
+    <Compile Include="Properties\AssemblyInfo.cs" />
+  </ItemGroup>
+  <ItemGroup>
+    <Content Include="favicon.ico" />
+    <Content Include="Global.asax" />
+    <Content Include="packages.config" />
+    <Content Include="Web.config" />
+  </ItemGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\..\src\SkyWalking.AspNet\SkyWalking.AspNet.csproj">
+      <Project>{3a454a8a-a1b7-4c6d-be08-52d956f95cc1}</Project>
+      <Name>SkyWalking.AspNet</Name>
+    </ProjectReference>
+  </ItemGroup>
+  <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
+  <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
+         Other similar extension points exist, see Microsoft.Common.targets.
+    <Target Name="BeforeBuild">
+    </Target>
+    <Target Name="AfterBuild">
+    </Target>
+    -->
+</Project>
\ No newline at end of file

sample/SkyWalking.Sample.AspNet/Web.config

+<?xml version="1.0" encoding="utf-8"?>
+<!--
+Web.config file for SkyWalking.Sample.AspNet.
+
+The settings that can be used in this file are documented at 
+http://www.mono-project.com/Config_system.web and 
+http://msdn2.microsoft.com/en-us/library/b5ysx397.aspx
+-->
+<configuration>
+  <appSettings>
+    <add key="ApplicationCode" value="aspnet-sample"/>
+    <add key="DirectServers" value="localhost:11800"/>
+   </appSettings>
+  <system.web>
+    <compilation debug="true" targetFramework="4.5">
+      <assemblies />
+    </compilation>
+    <httpRuntime targetFramework="4.5" />
+  </system.web>
+  <runtime>
+    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
+      <dependentAssembly>
+        <assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35" />
+        <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
+      </dependentAssembly>
+      <dependentAssembly>
+        <assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
+        <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
+      </dependentAssembly>
+      <dependentAssembly>
+        <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
+        <bindingRedirect oldVersion="1.0.0.0-5.2.3.0" newVersion="5.2.3.0" />
+      </dependentAssembly>
+    </assemblyBinding>
+  </runtime>
+</configuration>
\ No newline at end of file

sample/SkyWalking.Sample.AspNet/packages.config

+<?xml version="1.0" encoding="utf-8"?>
+<packages>
+  <package id="bootstrap" version="3.3.7" targetFramework="net45" />
+  <package id="jQuery" version="1.9.1" targetFramework="net45" />
+  <package id="Microsoft.AspNet.Mvc" version="5.2.3" targetFramework="net45" />
+  <package id="Microsoft.AspNet.Razor" version="3.2.3" targetFramework="net45" />
+  <package id="Microsoft.AspNet.WebApi" version="5.2.3" targetFramework="net45" />
+  <package id="Microsoft.AspNet.WebApi.Client" version="5.2.3" targetFramework="net45" />
+  <package id="Microsoft.AspNet.WebApi.Core" version="5.2.3" targetFramework="net45" />
+  <package id="Microsoft.AspNet.WebApi.WebHost" version="5.2.3" targetFramework="net45" />
+  <package id="Microsoft.AspNet.WebPages" version="3.2.3" targetFramework="net45" />
+  <package id="Microsoft.Web.Infrastructure" version="1.0.0.0" targetFramework="net45" />
+  <package id="Newtonsoft.Json" version="6.0.4" targetFramework="net45" />
+</packages>
\ No newline at end of file

skywalking-csharp.sln

@@ -58,6 +58,10 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SkyWalking.Diagnostics.Enti
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SkyWalking.Diagnostics.EntityFrameworkCore.Npgsql", "src\SkyWalking.Diagnostics.EntityFrameworkCore.Npgsql\SkyWalking.Diagnostics.EntityFrameworkCore.Npgsql.csproj", "{F8D96C30-369C-4FCB-B5B2-02EAA74199C9}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SkyWalking.AspNet", "src\SkyWalking.AspNet\SkyWalking.AspNet.csproj", "{3A454A8A-A1B7-4C6D-BE08-52D956F95CC1}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SkyWalking.Sample.AspNet", "sample\SkyWalking.Sample.AspNet\SkyWalking.Sample.AspNet.csproj", "{C3649845-E458-448D-B97D-C7E231E1D040}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -136,6 +140,14 @@ Global
 		{F8D96C30-369C-4FCB-B5B2-02EAA74199C9}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{F8D96C30-369C-4FCB-B5B2-02EAA74199C9}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{F8D96C30-369C-4FCB-B5B2-02EAA74199C9}.Release|Any CPU.Build.0 = Release|Any CPU
+		{3A454A8A-A1B7-4C6D-BE08-52D956F95CC1}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{3A454A8A-A1B7-4C6D-BE08-52D956F95CC1}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{3A454A8A-A1B7-4C6D-BE08-52D956F95CC1}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{3A454A8A-A1B7-4C6D-BE08-52D956F95CC1}.Release|Any CPU.Build.0 = Release|Any CPU
+		{C3649845-E458-448D-B97D-C7E231E1D040}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C3649845-E458-448D-B97D-C7E231E1D040}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C3649845-E458-448D-B97D-C7E231E1D040}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C3649845-E458-448D-B97D-C7E231E1D040}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -162,6 +174,8 @@ Global
 		{F5C529C9-23C4-46B7-84FF-E86C6D17EB3E} = {A4E67E09-3156-4D30-B451-F24F706E96C4}
 		{7BD880F3-2886-4EE6-9569-114613AFFCBC} = {A4E67E09-3156-4D30-B451-F24F706E96C4}
 		{F8D96C30-369C-4FCB-B5B2-02EAA74199C9} = {A4E67E09-3156-4D30-B451-F24F706E96C4}
+		{3A454A8A-A1B7-4C6D-BE08-52D956F95CC1} = {79ED86A5-E9B9-49B2-9354-C911C079D03E}
+		{C3649845-E458-448D-B97D-C7E231E1D040} = {844CEACD-4C85-4B15-9E2B-892B01FDA4BB}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {94C0DA2C-CCCB-4314-93A2-9809B5DD0583}

src/SkyWalking.Abstractions/Config/AgentConfig.cs

@@ -35,7 +35,7 @@ namespace SkyWalking.Config
         /// Negative number means sample traces as many as possible, most likely 100% , by default
         /// 
         /// </summary>
-        public static int Sample_N_Per_3_Secs = -1;
+        public static int SamplePer3Secs = -1;
 
         /// <summary>
         /// If the operation name of the first span is included in this set, this segment should be ignored.

src/SkyWalking.Abstractions/Context/Trace/AbstractTracingSpan.cs

@@ -22,6 +22,7 @@ using SkyWalking.Dictionarys;
 using SkyWalking.NetworkProtocol;
 using SkyWalking.NetworkProtocol.Trace;
 using System.Linq;
+using SkyWalking.Utils;
 
 namespace SkyWalking.Context.Trace
 {

src/SkyWalking.Abstractions/SkyWalking.Abstractions.csproj

@@ -3,7 +3,7 @@
   <PropertyGroup>
     <Description>SkyWalking Core abstractions and interfaces for apm agent.</Description>
     <AssemblyTitle>SkyWalking.Abstractions</AssemblyTitle>
-    <TargetFrameworks>netstandard2.0;net461</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;net45;net451</TargetFrameworks>
     <AssemblyName>SkyWalking.Abstractions</AssemblyName>
     <PackageId>SkyWalking.Abstractions</PackageId>
     <PackageTags>SkyWalking;APM</PackageTags>

src/SkyWalking.Abstractions/Utils/DateTimeOffsetExtensions.cs

+/*
+ * Licensed to the OpenSkywalking under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+using System;
+
+namespace SkyWalking.Utils
+{
+#if NET45 || NET451
+    public static class DateTimeOffsetExtensions
+    {
+        public static long ToUnixTimeMilliseconds(this DateTimeOffset dateTimeOffset)
+        {
+            return dateTimeOffset.UtcDateTime.Ticks / 10000L - 62135596800000L;
+        }
+    }
+#endif
+}

src/SkyWalking.AspNet/AsyncContext.cs

+/*
+ * Licensed to the OpenSkywalking under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace SkyWalking.AspNet
+{
+    internal class AsyncContext
+    {
+        public static void Run(Func<Task> task)
+        {
+            using (new ContextScope())
+            {
+                Task.Run(async () => await task()).GetAwaiter().GetResult();
+            }
+        }
+
+        private class ContextScope : IDisposable
+        {
+            private readonly SynchronizationContext _current;
+
+            public ContextScope()
+            {
+                _current = SynchronizationContext.Current;
+                SynchronizationContext.SetSynchronizationContext(null);
+            }
+
+            public void Dispose()
+            {
+                SynchronizationContext.SetSynchronizationContext(_current);
+            }
+        }
+    }
+}

src/SkyWalking.AspNet/HttpTracingHandler.cs

+/*
+ * Licensed to the OpenSkywalking under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+using System;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+using SkyWalking.Context;
+using SkyWalking.Context.Tag;
+using SkyWalking.Context.Trace;
+using SkyWalking.NetworkProtocol.Trace;
+
+namespace SkyWalking.AspNet
+{
+    public class HttpTracingHandler : DelegatingHandler
+    {
+        public HttpTracingHandler()
+            : this(new HttpClientHandler())
+        {
+        }
+
+        public HttpTracingHandler(HttpMessageHandler innerHandler)
+        {
+            InnerHandler = innerHandler;
+        }
+
+        protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request,
+            CancellationToken cancellationToken)
+        {
+            var peer = $"{request.RequestUri.Host}:{request.RequestUri.Port}";
+            var contextCarrier = new ContextCarrier();
+            var span = ContextManager.CreateExitSpan(request.RequestUri.ToString(), contextCarrier, peer);
+            try
+            {
+                Tags.Url.Set(span, request.RequestUri.ToString());
+                span.AsHttp();
+                span.SetComponent(ComponentsDefine.HttpClient);
+                Tags.HTTP.Method.Set(span, request.Method.ToString());
+                foreach (var item in contextCarrier.Items)
+                    request.Headers.Add(item.HeadKey, item.HeadValue);
+                var response = await base.SendAsync(request, cancellationToken);
+                Tags.StatusCode.Set(span, response.StatusCode.ToString());
+                return response;
+            }
+            catch (Exception e)
+            {
+                span.ErrorOccurred().Log(e);
+                throw;
+            }
+            finally
+            {
+                ContextManager.StopSpan(span);
+            }
+        }
+    }
+}

src/SkyWalking.AspNet/Logging/DebugLoggerAdapter.cs

+/*
+ * Licensed to the OpenSkywalking under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+using System;
+using SkyWalking.Logging;
+
+namespace SkyWalking.AspNet.Logging
+{
+    internal class DebugLoggerAdapter : ILogger
+    {
+        private readonly Type type;
+
+        public DebugLoggerAdapter(Type type)
+        {
+            this.type = type;
+        }
+
+        public void Debug(string message)
+        {
+            WriteLine("debug", message);
+        }
+
+        public void Info(string message)
+        {
+            WriteLine("info", message);
+        }
+
+        public void Warning(string message)
+        {
+            WriteLine("warn", message);
+        }
+
+        public void Error(string message, Exception exception)
+        {
+            WriteLine("error", message + Environment.NewLine + exception);
+        }
+
+        public void Trace(string message)
+        {
+            WriteLine("trace", message);
+        }
+
+        private void WriteLine(string level, string message)
+        {
+            System.Diagnostics.Debug.WriteLine($"{DateTime.Now} : [{level}] [{type.Name}] {message}");
+        }
+    }
+}
\ No newline at end of file

src/SkyWalking.AspNet/Logging/DebugLoggerFactoryAdapter.cs

+/*
+ * Licensed to the OpenSkywalking under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+using System;
+using System.Diagnostics;
+using SkyWalking.Logging;
+
+namespace SkyWalking.AspNet.Logging
+{
+    internal class DebugLoggerFactoryAdapter : ILoggerFactory
+    {
+        public DebugLoggerFactoryAdapter()
+        {
+            Debug.Listeners.Add(new TextWriterTraceListener(Console.Out));
+        }
+
+        public ILogger CreateLogger(Type type)
+        {
+            return new DebugLoggerAdapter(type);
+        }
+    }
+}

src/SkyWalking.AspNet/SkyWalking.AspNet.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+  <Import Project="..\..\build\common.props" />
+  <PropertyGroup>
+    <TargetFrameworks>net45;net451;net452;net46;net461;net462;net47;net471</TargetFrameworks>
+  </PropertyGroup>
+  <PropertyGroup>
+    <AssemblyName>SkyWalking.AspNet</AssemblyName>
+    <AssemblyTitle>SkyWalking.AspNet</AssemblyTitle>
+    <PackageId>SkyWalking.AspNet</PackageId>
+    <PackageTags>SkyWalking;APM;Tracing</PackageTags>
+    <Description>SkyWalking ASP.NET Agent.</Description>
+    <RootNamespace>SkyWalking.AspNet</RootNamespace>
+  </PropertyGroup>
+  <ItemGroup>
+    <ProjectReference Include="..\SkyWalking.Core\SkyWalking.Core.csproj" />
+  </ItemGroup>
+  <ItemGroup>
+    <Reference Include="System.Configuration" />
+    <Reference Include="System.Web" />
+    <Reference Include="System.Net.Http"/>
+  </ItemGroup>
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Web.Infrastructure" Version="1.0.0" />
+  </ItemGroup>
+</Project>
\ No newline at end of file

src/SkyWalking.AspNet/SkyWalkingModule.cs

+/*
+ * Licensed to the OpenSkywalking under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+using System;
+using System.Collections.Generic;
+using System.Web;
+using SkyWalking.Boot;
+using SkyWalking.Context;
+using SkyWalking.Context.Tag;
+using SkyWalking.Context.Trace;
+using SkyWalking.NetworkProtocol.Trace;
+using SkyWalking.Remote;
+using SkyWalking.Utils;
+
+namespace SkyWalking.AspNet
+{
+    public class SkyWalkingModule : IHttpModule
+    {
+        private readonly SkyWalkingStartup _skyWalkingStartup = new SkyWalkingStartup();
+        
+        public void Dispose()
+        {
+            _skyWalkingStartup.Dispose();
+        }
+
+        public void Init(HttpApplication application)
+        {
+            _skyWalkingStartup.Start();
+            application.BeginRequest += ApplicationOnBeginRequest;
+            application.EndRequest += ApplicationOnEndRequest;
+        }
+
+        private void ApplicationOnBeginRequest(object sender, EventArgs e)
+        {
+            var httpApplication = sender as HttpApplication;
+            var httpContext = httpApplication.Context;
+            var carrier = new ContextCarrier();
+            foreach (var item in carrier.Items)
+                item.HeadValue = httpContext.Request.Headers[item.HeadKey];
+            var httpRequestSpan = ContextManager.CreateEntrySpan($"{Config.AgentConfig.ApplicationCode} {httpContext.Request.Path}", carrier);
+            httpRequestSpan.AsHttp();
+            httpRequestSpan.SetComponent(ComponentsDefine.AspNet);
+            Tags.Url.Set(httpRequestSpan, httpContext.Request.Path);
+            Tags.HTTP.Method.Set(httpRequestSpan, httpContext.Request.HttpMethod);
+            httpRequestSpan.Log(DateTimeOffset.UtcNow.ToUnixTimeMilliseconds(),
+                new Dictionary<string, object>
+                {
+                    {"event", "AspNet BeginRequest"},
+                    {"message", $"Request starting {httpContext.Request.Url.Scheme} {httpContext.Request.HttpMethod} {httpContext.Request.Url.OriginalString}"}
+                });
+        }
+        
+        private void ApplicationOnEndRequest(object sender, EventArgs e)
+        {
+            var httpRequestSpan = ContextManager.ActiveSpan;
+            if (httpRequestSpan == null)
+            {
+                return;
+            }
+
+            var httpApplication = sender as HttpApplication;
+            var httpContext = httpApplication.Context;
+            
+            var statusCode = httpContext.Response.StatusCode;
+            if (statusCode >= 400)
+            {
+                httpRequestSpan.ErrorOccurred();
+            }
+
+            Tags.StatusCode.Set(httpRequestSpan, statusCode.ToString());
+
+            var exception = httpContext.Error;
+            if (exception != null)
+            {
+                httpRequestSpan.ErrorOccurred().Log(exception);
+            }
+            
+            httpRequestSpan.Log(DateTimeOffset.UtcNow.ToUnixTimeMilliseconds(),
+                new Dictionary<string, object>
+                {
+                    {"event", "AspNetCore Hosting EndRequest"},
+                    {"message", $"Request finished {httpContext.Response.StatusCode} {httpContext.Response.ContentType}"}
+                });
+            ContextManager.StopSpan(httpRequestSpan);
+        }
+    }
+}

src/SkyWalking.AspNet/SkyWalkingModuleRegister.cs

+/*
+ * Licensed to the OpenSkywalking under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+using Microsoft.Web.Infrastructure.DynamicModuleHelper;
+using System.Web;
+using SkyWalking.AspNet;
+
+[assembly:PreApplicationStartMethod(typeof(SkyWalkingModuleRegister), "Register")]
+
+namespace SkyWalking.AspNet
+{
+    public class SkyWalkingModuleRegister
+    {
+        public static void Register()
+        {
+            DynamicModuleUtility.RegisterModule(typeof(SkyWalkingModule));
+        }
+    }
+}
\ No newline at end of file

src/SkyWalking.AspNet/SkyWalkingOptions.cs

+/*
+ * Licensed to the OpenSkywalking under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+namespace SkyWalking.AspNet
+{
+    public class SkyWalkingOptions
+    {
+        /// <summary>
+        /// Application code is showed in sky-walking-ui
+        /// </summary>
+        public string ApplicationCode { get; set; }
+
+        /// <summary>
+        /// Collector agent_gRPC/grpc service addresses.
+        /// By using this, no discovery mechanism provided. The agent only uses these addresses to uplink data.
+        /// Recommend to use this only when collector cluster IPs are unreachable from agent side. Such as:
+        /// 1. Agent and collector cluster are in different VPC in Cloud.
+        /// 2. Agent uplinks data to collector cluster through Internet.
+        /// Single collector：DirectServers="127.0.0.1:11800"
+        /// Collector cluster：DirectServers="10.2.45.126:11800,10.2.45.127:11800"
+        /// </summary>
+        public string DirectServers { get; set; }
+
+        /// <summary>
+        /// The number of sampled traces per 3 seconds
+        /// Negative number means sample traces as many as possible, most likely 100% , by default
+        /// 
+        /// </summary>
+        public int SamplePer3Secs { get; set; } = -1;
+
+        /// <summary>
+        /// Namespace isolates headers in cross propagation. The HEADER name will be 'HeaderName:Namespace'.
+        /// </summary>
+        public string Namespace { get; set; }
+    }
+}
\ No newline at end of file

src/SkyWalking.AspNet/SkyWalkingStartup.cs

+/*
+ * Licensed to the OpenSkywalking under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+using System;
+using System.Reflection;
+using System.Threading.Tasks;
+using System.Web.Configuration;
+using SkyWalking.AspNet.Logging;
+using SkyWalking.Boot;
+using SkyWalking.Config;
+using SkyWalking.Logging;
+using SkyWalking.Remote;
+
+namespace SkyWalking.AspNet
+{
+    public class SkyWalkingStartup : IDisposable
+    {
+        public void Start()
+        {
+            LoadConfigurationSetting();
+            LogManager.SetLoggerFactory(new DebugLoggerFactoryAdapter());
+            AsyncContext.Run(async () => await StartAsync());
+        }
+
+        private async Task StartAsync()
+        {
+            await GrpcConnectionManager.Instance.ConnectAsync(TimeSpan.FromSeconds(3));
+            await ServiceManager.Instance.Initialize();
+        }
+
+        private void LoadConfigurationSetting()
+        {
+            CollectorConfig.DirectServers = GetAppSetting(nameof(CollectorConfig.DirectServers), true);
+            AgentConfig.ApplicationCode = GetAppSetting(nameof(AgentConfig.ApplicationCode), true);
+            AgentConfig.Namespace = GetAppSetting(nameof(AgentConfig.Namespace), false);
+            var samplePer3Secs = GetAppSetting(nameof(AgentConfig.SamplePer3Secs), false);
+            if (int.TryParse(samplePer3Secs, out var v))
+            {
+                AgentConfig.SamplePer3Secs = v;
+            }
+        }
+
+        private string GetAppSetting(string key, bool @throw)
+        {
+            var value = WebConfigurationManager.AppSettings[key];
+            if (@throw && string.IsNullOrEmpty(value))
+            {
+                throw new InvalidOperationException($"Cannot read valid '{key}' in AppSettings.");
+            }
+
+            return value;
+        }
+
+        public void Dispose()
+        {
+            AsyncContext.Run(async () => await GrpcConnectionManager.Instance.ShutdownAsync());
+            ServiceManager.Instance.Dispose();
+        }
+    }
+}

src/SkyWalking.AspNetCore/SkyWalkingHostedService.cs

@@ -53,7 +53,7 @@ namespace SkyWalking.AspNetCore
             LogManager.SetLoggerFactory(loggerFactory);
             AgentConfig.ApplicationCode = options.Value.ApplicationCode;
             CollectorConfig.DirectServers = options.Value.DirectServers;
-            AgentConfig.Sample_N_Per_3_Secs = options.Value.SamplePer3Secs;
+            AgentConfig.SamplePer3Secs = options.Value.SamplePer3Secs;
             _logger = LogManager.GetLogger<SkyWalkingHostedService>();
             _diagnosticObserver = diagnosticObserver;
         }

src/SkyWalking.Core/Boot/TimerService.cs

@@ -20,6 +20,7 @@ using System;
 using System.Threading;
 using System.Threading.Tasks;
 using SkyWalking.Logging;
+using SkyWalking.Utils;
 
 namespace SkyWalking.Boot
 {
@@ -59,12 +60,12 @@ namespace SkyWalking.Boot
 
         protected virtual Task Initializing(CancellationToken token)
         {
-            return Task.CompletedTask;
+            return TaskUtils.CompletedTask;
         }
 
         protected virtual Task Starting(CancellationToken token)
         {
-            return Task.CompletedTask;
+            return TaskUtils.CompletedTask;
         }
         
         protected abstract Task Execute(CancellationToken token);

src/SkyWalking.Core/Context/ContextManager.cs

@@ -24,6 +24,7 @@ using SkyWalking.Config;
 using SkyWalking.Context.Trace;
 using SkyWalking.Dictionarys;
 using SkyWalking.Sampling;
+using SkyWalking.Utils;
 
 namespace SkyWalking.Context
 {
@@ -185,7 +186,7 @@ namespace SkyWalking.Context
         {
             TracingContext.ListenerManager.Add(this);
             IgnoredTracerContext.ListenerManager.Add(this);
-            return Task.CompletedTask;
+            return TaskUtils.CompletedTask;
         }
 
         public void AfterFinish(ITracerContext tracerContext)

src/SkyWalking.Core/Context/Ids/GlobalIdGenerator.cs

@@ -20,6 +20,7 @@ using System;
 using System.Threading;
 using SkyWalking.Config;
 using SkyWalking.Dictionarys;
+using  SkyWalking.Utils;
 
 namespace SkyWalking.Context.Ids
 {
@@ -77,6 +78,7 @@ namespace SkyWalking.Context.Ids
                         _lastRandomValue = _random.Next();
                         _runRandomTimestamp = currentTimeMillis;
                     }
+
                     return _lastRandomValue;
                 }
                 else
@@ -92,6 +94,7 @@ namespace SkyWalking.Context.Ids
                 {
                     _threadSeq = 0;
                 }
+
                 return _threadSeq++;
             }
         }

src/SkyWalking.Core/Remote/GrpcApplicationService.cs

@@ -49,6 +49,11 @@ namespace SkyWalking.Remote
                 return;
             }
 
+            if (string.IsNullOrEmpty(AgentConfig.ApplicationCode))
+            {
+                return;
+            }
+
             if (!GrpcConnectionManager.Instance.Available)
             {
                 return;

src/SkyWalking.Core/Remote/GrpcHeartbeatService.cs

@@ -21,10 +21,10 @@ using System.Threading;
 using System.Threading.Tasks;
 using SkyWalking.Boot;
 using SkyWalking.Config;
-using SkyWalking.Context;
 using SkyWalking.Dictionarys;
 using SkyWalking.Logging;
 using SkyWalking.NetworkProtocol;
+using SkyWalking.Utils;
 
 namespace SkyWalking.Remote
 {

src/SkyWalking.Core/Remote/GrpcRuntimeService.cs

@@ -20,6 +20,7 @@ using System;
 using System.Threading;
 using System.Threading.Tasks;
 using SkyWalking.Boot;
+using SkyWalking.Utils;
 
 namespace SkyWalking.Remote
 {
@@ -30,7 +31,7 @@ namespace SkyWalking.Remote
         protected override Task Execute(CancellationToken token)
         {
             // todo 
-            return Task.CompletedTask;
+            return TaskUtils.CompletedTask;
         }
     }
 }
\ No newline at end of file

src/SkyWalking.Core/Remote/GrpcTraceSegmentService.cs

@@ -25,6 +25,7 @@ using SkyWalking.Context;
 using SkyWalking.Context.Trace;
 using SkyWalking.Logging;
 using SkyWalking.NetworkProtocol;
+using SkyWalking.Utils;
 
 namespace SkyWalking.Remote
 {
@@ -42,7 +43,7 @@ namespace SkyWalking.Remote
         public Task Initialize(CancellationToken token)
         {
             TracingContext.ListenerManager.Add(this);
-            return Task.CompletedTask;
+            return TaskUtils.CompletedTask;
         }
 
         public async void AfterFinished(ITraceSegment traceSegment)

src/SkyWalking.Core/Sampling/SamplingService.cs

@@ -29,8 +29,8 @@ namespace SkyWalking.Sampling
     public class SamplingService :TimerService, ISampler
     {
         private readonly AtomicInteger _atomicInteger = new AtomicInteger();
-        private readonly int _sample_N_Per_3_Secs = AgentConfig.Sample_N_Per_3_Secs;
-        private readonly bool _sample_on = AgentConfig.Sample_N_Per_3_Secs > 0;
+        private readonly int _sample_N_Per_3_Secs = AgentConfig.SamplePer3Secs;
+        private readonly bool _sample_on = AgentConfig.SamplePer3Secs > 0;
 
         public bool TrySampling()
         {
@@ -59,7 +59,7 @@ namespace SkyWalking.Sampling
                 _atomicInteger.Value = 0;
             }
 
-            return Task.CompletedTask;
+            return TaskUtils.CompletedTask;
         }
     }
 }
\ No newline at end of file

src/SkyWalking.Core/SkyWalking.Core.csproj

@@ -3,7 +3,7 @@
   <PropertyGroup>
     <Description>SkyWalking core components.</Description>
     <AssemblyTitle>SkyWalking.Core</AssemblyTitle>
-    <TargetFrameworks>netstandard2.0;net461</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;net45;net451</TargetFrameworks>
     <AssemblyName>SkyWalking.Core</AssemblyName>
     <PackageId>SkyWalking.Core</PackageId>
     <PackageTags>SkyWalking;APM</PackageTags>

src/SkyWalking.Core/Utils/AsyncLocal.cs

+/*
+ * Licensed to the OpenSkywalking under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#if NET45 || NET451
+using System.Runtime.Remoting.Messaging;
+
+namespace SkyWalking.Utils
+{
+    internal class AsyncLocal<T>
+    {
+        private static readonly string key = "sw-" + typeof(T).FullName;
+
+        public T Value
+        {
+            get => (T) CallContext.LogicalGetData(key);
+            set => CallContext.LogicalSetData(key, value);
+        }
+    }
+}
+#endif

src/SkyWalking.Core/Utils/TaskUtils.cs

+/*
+ * Licensed to the OpenSkywalking under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+using System.Threading.Tasks;
+
+namespace SkyWalking.Utils
+{
+    internal static class TaskUtils
+    {
+        public static readonly Task CompletedTask = Task.FromResult(0);
+    }
+}
\ No newline at end of file

src/SkyWalking.NetworkProtocol.Trace/ComponentsDefine.cs

@@ -53,6 +53,8 @@ namespace SkyWalking.NetworkProtocol.Trace
         
         public static readonly OfficialComponent InMemoryDatabase = new OfficialComponent(3014, "InMemoryDatabase");
         
+        public static readonly OfficialComponent AspNet = new OfficialComponent(3015, "AspNet");
+        
         private static readonly ComponentsDefine _instance = new ComponentsDefine();
 
         public ComponentsDefine Instance => _instance;
@@ -76,6 +78,7 @@ namespace SkyWalking.NetworkProtocol.Trace
             AddComponent(Pomelo_EntityFrameworkCore_MySql);
             AddComponent(Npgsql_EntityFrameworkCore_PostgreSQL);
             AddComponent(InMemoryDatabase);
+            AddComponent(AspNet);
         }
 
         private void AddComponent(OfficialComponent component)

src/SkyWalking.NetworkProtocol.Trace/SkyWalking.NetworkProtocol.Trace.csproj

@@ -3,7 +3,7 @@
   <PropertyGroup>
     <Description>SkyWalking trace protocol.</Description>
     <AssemblyTitle>SkyWalking.NetworkProtocol.Trace</AssemblyTitle>
-    <TargetFrameworks>netstandard2.0;net461</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;net45</TargetFrameworks>
     <AssemblyName>SkyWalking.NetworkProtocol.Trace</AssemblyName>
     <PackageId>SkyWalking.NetworkProtocol.Trace</PackageId>
     <PackageTags>SkyWalking</PackageTags>

src/SkyWalking.NetworkProtocol/SkyWalking.NetworkProtocol.csproj

@@ -3,7 +3,7 @@
   <PropertyGroup>
     <Description>SkyWalking gRPC protocol and generated codes.</Description>
     <AssemblyTitle>SkyWalking.NetworkProtocol</AssemblyTitle>
-    <TargetFrameworks>netstandard2.0;net461</TargetFrameworks>
+    <TargetFrameworks>netstandard2.0;net45</TargetFrameworks>
     <AssemblyName>SkyWalking.NetworkProtocol</AssemblyName>
     <PackageId>SkyWalking.NetworkProtocol</PackageId>
     <PackageTags>SkyWalking</PackageTags>