Refactor SkyWalking.Diagnostics (#35)

* Downgrade dependencies

* Refactor SkyWalking.Diagnostics

* Add ParameterBinder

* Fix null parameter

* Add unit tests for SkyWalking.Diagnostics

* Fix property binding

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

-using System;
-using System.Collections.Generic;
-using System.Linq;
+using System.Collections.Generic;
 using System.Net.Http;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Mvc;

sample/SkyWalking.Sample.Backend/Startup.cs

@@ -3,7 +3,6 @@ using Microsoft.AspNetCore.Hosting;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using SkyWalking.AspNetCore;
-using SkyWalking.Diagnostics.CAP;
 
 namespace SkyWalking.Sample.Backend
 {
@@ -21,17 +20,11 @@ namespace SkyWalking.Sample.Backend
         {
             services.AddMvc();
 
-            //services.AddCap(x =>
-            //{
-            //    x.UseKafka("192.168.10.110:9092");
-            //    x.UseMySql("Server=192.168.10.110;Database=testcap;UserId=root;Password=123123;");
-            //});
-
             services.AddSkyWalking(option =>
             {
                 option.DirectServers = "localhost:11800";
                 option.ApplicationCode = "asp-net-core-backend";
-            });//.AddCap();
+            });
         }
 
         // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
@@ -43,8 +36,6 @@ namespace SkyWalking.Sample.Backend
             }
 
             app.UseMvc();
-
-           // app.UseCap();
         }
     }
 }
\ No newline at end of file

src/SkyWalking.AspNetCore/Diagnostics/HostingDiagnosticProcessor.cs

@@ -18,7 +18,6 @@
 
 using System;
 using Microsoft.AspNetCore.Http;
-using Microsoft.Extensions.DiagnosticAdapter;
 using SkyWalking.Context;
 using SkyWalking.Context.Tag;
 using SkyWalking.Context.Trace;

src/SkyWalking.AspNetCore/Extensions/SkyWalkingBuilderExtensions.cs

@@ -39,7 +39,7 @@ namespace SkyWalking.AspNetCore
 
         public static SkyWalkingBuilder AddDiagnostics(this SkyWalkingBuilder builder)
         {
-            builder.Services.AddSingleton<TracingDiagnosticObserver, AdatpeTracingDiagnosticObserver>();
+            builder.Services.AddSingleton<TracingDiagnosticProcessorObserver>();
             return builder;
         }
 

src/SkyWalking.AspNetCore/SkyWalking.AspNetCore.csproj

@@ -15,7 +15,6 @@
     <PackageReference Include="Microsoft.AspNetCore.Hosting" Version="2.0.0" />
     <PackageReference Include="Microsoft.AspNetCore.Http.Abstractions" Version="2.0.0" />
     <PackageReference Include="Microsoft.AspNetCore.Mvc.Abstractions" Version="2.0.0" />
-    <PackageReference Include="Microsoft.Extensions.DiagnosticAdapter" Version="2.1.0-preview2-final" />
     <PackageReference Include="Microsoft.Extensions.Http" Version="2.1.0-preview2-final" />
     <PackageReference Include="Microsoft.Extensions.Logging.Abstractions" Version="2.1.0-preview2-final" />
     <PackageReference Include="Microsoft.Extensions.Options" Version="2.1.0-preview2-final" />

src/SkyWalking.AspNetCore/SkyWalkingHostedService.cs

@@ -33,11 +33,11 @@ namespace SkyWalking.AspNetCore
 {
     public class SkyWalkingHostedService : IHostedService
     {
-        private readonly TracingDiagnosticObserver _diagnosticObserver;
+        private readonly TracingDiagnosticProcessorObserver _diagnosticObserver;
         private readonly ILogger _logger;
 
         public SkyWalkingHostedService(IOptions<SkyWalkingOptions> options, IHostingEnvironment hostingEnvironment,
-            TracingDiagnosticObserver diagnosticObserver, ILoggerFactory loggerFactory)
+            TracingDiagnosticProcessorObserver diagnosticObserver, ILoggerFactory loggerFactory)
         {
        
             if (string.IsNullOrEmpty(options.Value.DirectServers))

src/SkyWalking.Core/Diagnostics/AnonymousObject.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.Diagnostics
+{
+    public class AnonymousObject : ParameterBinder
+    {
+        public override object Resolve(object value)
+        {
+            return value;
+        }
+    }
+}
\ No newline at end of file

src/SkyWalking.AspNetCore/Diagnostics/AdatpeTracingDiagnosticObserver.cs → src/SkyWalking.Core/Diagnostics/DiagnosticName.cs

@@ -16,22 +16,17 @@
  *
  */
 
-using System.Collections.Generic;
-using System.Diagnostics;
-using SkyWalking.Diagnostics;
+using System;
 
-namespace SkyWalking.AspNetCore.Diagnostics
+namespace SkyWalking.Diagnostics
 {
-    public class AdatpeTracingDiagnosticObserver : TracingDiagnosticObserver
+    public class DiagnosticName :Attribute
     {
-        public AdatpeTracingDiagnosticObserver(IEnumerable<ITracingDiagnosticProcessor> tracingDiagnosticProcessors) 
-            : base(tracingDiagnosticProcessors)
-        {
-        }
+        public string Name { get; }
 
-        protected override void OnNext(DiagnosticListener listener, ITracingDiagnosticProcessor diagnosticProcessor)
+        public DiagnosticName(string name)
         {
-            listener.SubscribeWithAdapter(diagnosticProcessor);
+            Name = name;
         }
     }
 }
\ No newline at end of file

src/SkyWalking.Core/Diagnostics/IParameterResolver.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.Diagnostics
+{
+    public interface IParameterResolver
+    {
+        object Resolve(object value);
+    }
+}
\ No newline at end of file

src/SkyWalking.Core/Diagnostics/NullParameterResolver.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.Diagnostics
+{
+    public class NullParameterResolver : IParameterResolver
+    {
+        public object Resolve(object value)
+        {
+            return null;
+        }
+    }
+}
\ No newline at end of file

src/SkyWalking.Core/Diagnostics/ObjectAttribute.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.Diagnostics
+{
+    public class ObjectAttribute : ParameterBinder
+    {
+        public Type TargetType { get; set; }
+
+        public override object Resolve(object value)
+        {
+            if (TargetType == null || value == null)
+            {
+                return value;
+            }
+
+            if (TargetType == value.GetType())
+            {
+                return value;
+            }
+
+            if (TargetType.IsInstanceOfType(value))
+            {
+                return value;
+            }
+
+            return null;
+        }
+    }
+}
\ No newline at end of file

src/SkyWalking.Core/Diagnostics/ParameterBinder.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.Diagnostics
+{
+    public abstract class ParameterBinder : Attribute, IParameterResolver
+    {
+        public abstract object Resolve(object value);
+    }
+}
\ No newline at end of file

src/SkyWalking.Core/Diagnostics/PropertyAttribute.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.Diagnostics
+{
+    public class PropertyAttribute : ParameterBinder
+    {
+        public string Name { get; set; }
+
+        public override object Resolve(object value)
+        {
+            if (value == null || Name == null)
+            {
+                return null;
+            }
+
+            var property = value.GetType().GetProperty(Name);
+            
+            return property?.GetValue(value);
+        }
+    }
+}
\ No newline at end of file

src/SkyWalking.Core/Diagnostics/TracingDiagnosticMethod.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.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+
+namespace SkyWalking.Diagnostics
+{
+    internal class TracingDiagnosticMethod
+    {
+        private readonly MethodInfo _method;
+        private readonly ITracingDiagnosticProcessor _diagnosticProcessor;
+        private readonly string _diagnosticName;
+        private readonly IParameterResolver[] _parameterResolvers;
+
+        public TracingDiagnosticMethod(ITracingDiagnosticProcessor diagnosticProcessor, MethodInfo method,
+            string diagnosticName)
+        {
+            _diagnosticProcessor = diagnosticProcessor;
+            _method = method;
+            _diagnosticName = diagnosticName;
+            _parameterResolvers = GetParameterResolvers(method).ToArray();
+        }
+
+        public void Invoke(string diagnosticName, object value)
+        {
+            if (_diagnosticName != diagnosticName)
+            {
+                return;
+            }
+
+            var args = new object[_parameterResolvers.Length];
+            for (var i = 0; i < _parameterResolvers.Length; i++)
+            {
+                args[i] = _parameterResolvers[i].Resolve(value);
+            }
+
+            _method.Invoke(_diagnosticProcessor, args);
+        }
+
+        private static IEnumerable<IParameterResolver> GetParameterResolvers(MethodInfo methodInfo)
+        {
+            foreach (var parameter in methodInfo.GetParameters())
+            {
+                var binder = parameter.GetCustomAttribute<ParameterBinder>();
+                if (binder != null)
+                {
+                    if(binder is ObjectAttribute objectBinder)
+                    {
+                        if (objectBinder.TargetType == null)
+                        {
+                            objectBinder.TargetType = parameter.ParameterType;
+                        }
+                    }
+                    if(binder is PropertyAttribute propertyBinder)
+                    {
+                        if (propertyBinder.Name == null)
+                        {
+                            propertyBinder.Name = parameter.Name;
+                        }
+                    }
+                    yield return binder;
+                }
+                else
+                {
+                    yield return new NullParameterResolver();
+                }
+            }
+        }
+    }
+}
\ No newline at end of file

src/SkyWalking.Core/Diagnostics/TracingDiagnosticMethodCollection.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.Collections;
+using System.Collections.Generic;
+using System.Reflection;
+
+namespace SkyWalking.Diagnostics
+{
+    internal class TracingDiagnosticMethodCollection : IEnumerable<TracingDiagnosticMethod>
+    {
+        private readonly List<TracingDiagnosticMethod> _methods;
+
+        public TracingDiagnosticMethodCollection(ITracingDiagnosticProcessor diagnosticProcessor)
+        {
+            _methods = new List<TracingDiagnosticMethod>();
+            foreach (var method in diagnosticProcessor.GetType().GetMethods())
+            {
+                var diagnosticName = method.GetCustomAttribute<DiagnosticName>();
+                if(diagnosticName==null)
+                    continue;
+                _methods.Add(new TracingDiagnosticMethod(diagnosticProcessor, method, diagnosticName.Name));
+            }
+        }
+        
+        public IEnumerator<TracingDiagnosticMethod> GetEnumerator()
+        {
+            return _methods.GetEnumerator();
+        }
+
+        IEnumerator IEnumerable.GetEnumerator()
+        {
+            return _methods.GetEnumerator();
+        }
+    }
+}
\ No newline at end of file

src/SkyWalking.Core/Diagnostics/TracingDiagnosticObserver.cs

@@ -18,22 +18,16 @@
 
 using System;
 using System.Collections.Generic;
-using System.Diagnostics;
-using SkyWalking.Logging;
-using SkyWalking.Utils;
 
 namespace SkyWalking.Diagnostics
 {
-    public abstract class TracingDiagnosticObserver : IObserver<DiagnosticListener>
+    internal class TracingDiagnosticObserver : IObserver<KeyValuePair<string, object>>
     {
-        private static readonly ILogger _logger = LogManager.GetLogger<TracingDiagnosticObserver>();
+        private readonly TracingDiagnosticMethodCollection _methodCollection;
 
-        private readonly IEnumerable<ITracingDiagnosticProcessor> _tracingDiagnosticProcessors;
-
-        public TracingDiagnosticObserver(IEnumerable<ITracingDiagnosticProcessor> tracingDiagnosticProcessors)
+        public TracingDiagnosticObserver(ITracingDiagnosticProcessor tracingDiagnosticProcessor)
         {
-            _tracingDiagnosticProcessors = tracingDiagnosticProcessors ??
-                                           throw new ArgumentNullException(nameof(tracingDiagnosticProcessors));
+            _methodCollection = new TracingDiagnosticMethodCollection(tracingDiagnosticProcessor);
         }
 
         public void OnCompleted()
@@ -44,19 +38,12 @@ namespace SkyWalking.Diagnostics
         {
         }
 
-        public void OnNext(DiagnosticListener listener)
-        {
-            foreach (var diagnosticProcessor in _tracingDiagnosticProcessors.Distinct(x => x.ListenerName))
+        public void OnNext(KeyValuePair<string, object> value)
         {
-                if (listener.Name == diagnosticProcessor.ListenerName)
+            foreach (var method in _methodCollection)
             {
-                    OnNext(listener, diagnosticProcessor);
-                    _logger.Debug($"TracingDiagnosticObserver subscribe diagnosticListener named [{diagnosticProcessor.ListenerName}].");
+                method.Invoke(value.Key, value.Value);
             }
         }
     }
-
-        protected abstract void OnNext(DiagnosticListener listener,
-            ITracingDiagnosticProcessor diagnosticProcessor);
-    }
 }
\ No newline at end of file

src/SkyWalking.Core/Diagnostics/TracingDiagnosticProcessorObserver.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.Diagnostics;
+using SkyWalking.Logging;
+using SkyWalking.Utils;
+
+namespace SkyWalking.Diagnostics
+{
+    public class TracingDiagnosticProcessorObserver : IObserver<DiagnosticListener>
+    {
+        private static readonly ILogger _logger = LogManager.GetLogger<TracingDiagnosticProcessorObserver>();
+
+        private readonly IEnumerable<ITracingDiagnosticProcessor> _tracingDiagnosticProcessors;
+
+        public TracingDiagnosticProcessorObserver(IEnumerable<ITracingDiagnosticProcessor> tracingDiagnosticProcessors)
+        {
+            _tracingDiagnosticProcessors = tracingDiagnosticProcessors ??
+                                           throw new ArgumentNullException(nameof(tracingDiagnosticProcessors));
+        }
+
+        public void OnCompleted()
+        {
+        }
+
+        public void OnError(Exception error)
+        {
+        }
+
+        public void OnNext(DiagnosticListener listener)
+        {
+            foreach (var diagnosticProcessor in _tracingDiagnosticProcessors.Distinct(x => x.ListenerName))
+            {
+                if (listener.Name == diagnosticProcessor.ListenerName)
+                {
+                    Subscribe(listener, diagnosticProcessor);
+                    _logger.Debug(
+                        $"TracingDiagnosticObserver subscribe diagnosticListener named [{diagnosticProcessor.ListenerName}].");
+                }
+            }
+        }
+
+        protected virtual void Subscribe(DiagnosticListener listener,
+            ITracingDiagnosticProcessor diagnosticProcessor)
+        {
+            listener.Subscribe(new TracingDiagnosticObserver(diagnosticProcessor));
+        }
+    }
+}
\ No newline at end of file

src/SkyWalking.Core/Logging/NullLoggerFactory.cs

@@ -24,7 +24,7 @@ namespace SkyWalking.Logging
     {
         public ILogger CreateLogger(Type type)
         {
-            return null;
+            return new NullLogger();
         }
     }
 }
\ No newline at end of file

src/SkyWalking.Core/SkyWalking.Core.csproj

@@ -13,6 +13,8 @@
   </PropertyGroup>
   <ItemGroup>
     <ProjectReference Include="..\SkyWalking.Abstractions\SkyWalking.Abstractions.csproj" />
+    <ProjectReference Include="..\SkyWalking.NetworkProtocol.Trace\SkyWalking.NetworkProtocol.Trace.csproj" />
+    <ProjectReference Include="..\SkyWalking.NetworkProtocol\SkyWalking.NetworkProtocol.csproj" />
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="Nito.AsyncEx.Coordination" Version="5.0.0-pre-05" />

src/SkyWalking.Diagnostics.CAP/CapDiagnosticProcessor.cs

@@ -19,7 +19,6 @@
 using System;
 using DotNetCore.CAP.Diagnostics;
 using DotNetCore.CAP.Infrastructure;
-using Microsoft.Extensions.DiagnosticAdapter;
 using SkyWalking.Context;
 using SkyWalking.Context.Tag;
 using SkyWalking.Context.Trace;

src/SkyWalking.Diagnostics.CAP/SkyWalking.Diagnostics.CAP.csproj

@@ -17,7 +17,6 @@
 
   <ItemGroup>
     <PackageReference Include="DotNetCore.CAP" Version="2.2.2" />
-    <PackageReference Include="Microsoft.Extensions.DiagnosticAdapter" Version="2.1.0-preview2-final" />
   </ItemGroup>
 
   <ItemGroup>

src/SkyWalking.Diagnostics.HttpClient/HttpClientDiagnosticProcessor.cs

@@ -16,9 +16,7 @@
  *
  */
 
-using System.Diagnostics;
 using System.Net.Http;
-using Microsoft.Extensions.DiagnosticAdapter;
 using SkyWalking.Context;
 using SkyWalking.Context.Tag;
 using SkyWalking.Context.Trace;

src/SkyWalking.Diagnostics.HttpClient/SkyWalking.Diagnostics.HttpClient.csproj

 <Project Sdk="Microsoft.NET.Sdk">
+  
   <Import Project="..\..\build\common.props" />
 
   <PropertyGroup>
@@ -13,10 +14,6 @@
     <RootNamespace>SkyWalking.Diagnostics.HttpClient</RootNamespace>
   </PropertyGroup>
 
-  <ItemGroup>
-    <PackageReference Include="Microsoft.Extensions.DiagnosticAdapter" Version="2.1.0-preview2-final" />
-  </ItemGroup>
-
   <ItemGroup>
     <ProjectReference Include="..\SkyWalking.Abstractions\SkyWalking.Abstractions.csproj" />
     <ProjectReference Include="..\SkyWalking.Core\SkyWalking.Core.csproj" />

test/SkyWalking.Core.Tests/Diagnostics/FakeDiagnosticListener.cs

+using System.Diagnostics;
+
+namespace SkyWalking.Core.Tests.Diagnostics
+{
+    public class FakeDiagnosticListener : DiagnosticListener
+    {
+        public const string ListenerName = "SkyWalking.Core.Tests.Diagnostics";
+
+        public const string Executing = "Executing";
+
+        public const string Executed = "Executed";
+        
+        public FakeDiagnosticListener() : base(ListenerName)
+        {
+        }
+    }
+}
\ No newline at end of file

test/SkyWalking.Core.Tests/Diagnostics/FakeDiagnosticListenerData.cs

+using System;
+
+namespace SkyWalking.Core.Tests.Diagnostics
+{
+    public class FakeDiagnosticListenerData
+    {
+        public string Name { get; set; }
+        
+        public DateTime Timestamp { get; set; }
+    }
+}
\ No newline at end of file

test/SkyWalking.Core.Tests/Diagnostics/FakeTracingDiagnosticProcessor.cs

+using System;
+using SkyWalking.Diagnostics;
+using Xunit;
+    
+namespace SkyWalking.Core.Tests.Diagnostics
+{
+    public class FakeTracingDiagnosticProcessor : ITracingDiagnosticProcessor
+    {
+        public string ListenerName { get; } = FakeDiagnosticListener.ListenerName;
+        
+        public DateTime Timestamp { get; set; }
+
+        [DiagnosticName(FakeDiagnosticListener.Executing)]
+        public void Executing(
+            [PropertyAttribute(Name = "Name")] string eventName, 
+            [Property] DateTime Timestamp)
+        {
+            Assert.Equal("Executing", eventName);
+            this.Timestamp = Timestamp;
+        }
+
+        [DiagnosticName(FakeDiagnosticListener.Executed)]
+        public void Executed([Object] FakeDiagnosticListenerData data)
+        {
+            Assert.Equal("Executed", data.Name);
+            Timestamp = data.Timestamp;
+        }
+    }
+}
\ No newline at end of file

test/SkyWalking.Core.Tests/Diagnostics/TracingDiagnosticProcessorObserverTests.cs

+using System;
+using System.Diagnostics;
+using SkyWalking.Diagnostics;
+using Xunit;
+
+namespace SkyWalking.Core.Tests.Diagnostics
+{
+    public class TracingDiagnosticProcessorObserverTests
+    {
+        [Fact]
+        public void Property_Binder_Invoke_Test()
+        {
+            var listener = new FakeDiagnosticListener();
+            var fakeProcessor = new FakeTracingDiagnosticProcessor();
+            var observer = new TracingDiagnosticProcessorObserver(new ITracingDiagnosticProcessor[] {fakeProcessor});
+            DiagnosticListener.AllListeners.Subscribe(observer);
+
+            var timeStamp = DateTime.Now;
+            listener.Write(FakeDiagnosticListener.Executing,
+                new
+                {
+                    Name = FakeDiagnosticListener.Executing,
+                    Timestamp = timeStamp
+                });
+
+            Assert.Equal(timeStamp, fakeProcessor.Timestamp);      
+        }
+
+        [Fact]
+        public void Object_Binder_Invoke_Test()
+        {
+            var listener = new FakeDiagnosticListener();
+            var fakeProcessor = new FakeTracingDiagnosticProcessor();
+            var observer = new TracingDiagnosticProcessorObserver(new ITracingDiagnosticProcessor[] {fakeProcessor});
+            DiagnosticListener.AllListeners.Subscribe(observer);
+
+            var timeStamp = DateTime.Now;
+            
+            listener.Write(FakeDiagnosticListener.Executed,
+                new FakeDiagnosticListenerData
+                {
+                    Name = FakeDiagnosticListener.Executed,
+                    Timestamp = timeStamp
+                });
+            
+            Assert.Equal(timeStamp, fakeProcessor.Timestamp);
+        }
+    }
+}
\ No newline at end of file