[Logs] OpenTelemetry.Extensions.EventSource extensions project (#3454)

* Add OpenTelemetryEventSourceLogEmitter.

* Project rename.

* Started tests.

* Added behavior comment in example.

* Add  --prerelease in READMEs.

* Example tweaks.

* Test improvements.

* Added activity_id/related_activity_id test.

* Warning cleanup.

OpenTelemetry.sln

@@ -235,6 +235,10 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "OpenTelemetry.Extensions.Se
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "OpenTelemetry.Extensions.Serilog.Tests", "test\OpenTelemetry.Extensions.Serilog.Tests\OpenTelemetry.Extensions.Serilog.Tests.csproj", "{6A2C122A-C1CD-4B6B-AE09-2ABB7D3C50CE}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "OpenTelemetry.Extensions.EventSource", "src\OpenTelemetry.Extensions.EventSource\OpenTelemetry.Extensions.EventSource.csproj", "{7AFB4975-9680-4668-9F5E-C3F0CA41E982}"
+EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "OpenTelemetry.Extensions.EventSource.Tests", "test\OpenTelemetry.Extensions.EventSource.Tests\OpenTelemetry.Extensions.EventSource.Tests.csproj", "{304FCFFF-97DE-484B-8D8C-612C644426E5}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -481,6 +485,14 @@ Global
 		{6A2C122A-C1CD-4B6B-AE09-2ABB7D3C50CE}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{6A2C122A-C1CD-4B6B-AE09-2ABB7D3C50CE}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{6A2C122A-C1CD-4B6B-AE09-2ABB7D3C50CE}.Release|Any CPU.Build.0 = Release|Any CPU
+		{7AFB4975-9680-4668-9F5E-C3F0CA41E982}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{7AFB4975-9680-4668-9F5E-C3F0CA41E982}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{7AFB4975-9680-4668-9F5E-C3F0CA41E982}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{7AFB4975-9680-4668-9F5E-C3F0CA41E982}.Release|Any CPU.Build.0 = Release|Any CPU
+		{304FCFFF-97DE-484B-8D8C-612C644426E5}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{304FCFFF-97DE-484B-8D8C-612C644426E5}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{304FCFFF-97DE-484B-8D8C-612C644426E5}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{304FCFFF-97DE-484B-8D8C-612C644426E5}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

examples/LoggingExtensions/ExampleEventSource.cs

@@ -0,0 +1,33 @@
+// <copyright file="ExampleEventSource.cs" company="OpenTelemetry Authors">
+// Copyright The OpenTelemetry Authors
+//
+// Licensed 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.
+// </copyright>
+
+using System.Diagnostics.Tracing;
+
+namespace Examples.LoggingExtensions;
+
+[EventSource(Name = EventSourceName)]
+internal sealed class ExampleEventSource : EventSource
+{
+    public const string EventSourceName = "OpenTelemetry-ExampleEventSource";
+
+    public static ExampleEventSource Log { get; } = new();
+
+    [Event(1, Message = "Example event written with '{0}' reason", Level = EventLevel.Informational)]
+    public void ExampleEvent(string reason)
+    {
+        this.WriteEvent(1, reason);
+    }
+}

examples/LoggingExtensions/Examples.LoggingExtensions.csproj

@@ -10,6 +10,7 @@
   <ItemGroup>
     <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Exporter.Console\OpenTelemetry.Exporter.Console.csproj" />
     <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Extensions.Serilog\OpenTelemetry.Extensions.Serilog.csproj" />
+    <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry.Extensions.EventSource\OpenTelemetry.Extensions.EventSource.csproj" />
   </ItemGroup>
 
 </Project>

examples/LoggingExtensions/Program.cs

@@ -14,14 +14,14 @@
 // limitations under the License.
 // </copyright>
 
+using System.Diagnostics.Tracing;
+using Examples.LoggingExtensions;
 using OpenTelemetry.Logs;
 using OpenTelemetry.Resources;
 using Serilog;
 
-var resourceBuilder = ResourceBuilder.CreateDefault().AddService("Examples.LogEmitter");
+var resourceBuilder = ResourceBuilder.CreateDefault().AddService("Examples.LoggingExtensions");
 
-// Note: It is important that OpenTelemetryLoggerProvider is disposed when the
-// app is shutdown. In this example we allow Serilog to do that by calling CloseAndFlush.
 var openTelemetryLoggerProvider = new OpenTelemetryLoggerProvider(options =>
 {
     options.IncludeFormattedMessage = true;
@@ -30,18 +30,29 @@
         .AddConsoleExporter();
 });
 
+// Creates an OpenTelemetryEventSourceLogEmitter for routing ExampleEventSource
+// events into logs
+using var openTelemetryEventSourceLogEmitter = new OpenTelemetryEventSourceLogEmitter(
+    openTelemetryLoggerProvider, // <- Events will be written to openTelemetryLoggerProvider
+    (name) => name == ExampleEventSource.EventSourceName ? EventLevel.Informational : null,
+    disposeProvider: false); // <- Do not dispose the provider with OpenTelemetryEventSourceLogEmitter since in this case it is shared with Serilog
+
 // Configure Serilog global logger
 Log.Logger = new LoggerConfiguration()
-    .WriteTo.OpenTelemetry(openTelemetryLoggerProvider, disposeProvider: true) // <- Register OpenTelemetry Serilog sink
+    .WriteTo.OpenTelemetry(
+        openTelemetryLoggerProvider, // <- Register OpenTelemetry Serilog sink writing to openTelemetryLoggerProvider
+        disposeProvider: false) // <- Do not dispose the provider with Serilog since in this case it is shared with OpenTelemetryEventSourceLogEmitter
     .CreateLogger();
 
+ExampleEventSource.Log.ExampleEvent("Startup complete");
+
 // Note: Serilog ForContext API is used to set "CategoryName" on log messages
 ILogger programLogger = Log.Logger.ForContext<Program>();
 
 programLogger.Information("Application started {Greeting} {Location}", "Hello", "World");
 
-programLogger.Information("Message {Array}", new string[] { "value1", "value2" });
-
-// Note: For Serilog this call flushes all logs and disposes
-// OpenTelemetryLoggerProvider.
+// Note: For Serilog this call flushes all logs
 Log.CloseAndFlush();
+
+// Manually dispose OpenTelemetryLoggerProvider since it is being shared
+openTelemetryLoggerProvider.Dispose();

src/OpenTelemetry.Extensions.EventSource/.publicApi/netstandard2.0/PublicAPI.Shipped.txt

@@ -0,0 +1 @@
+#nullable enable

src/OpenTelemetry.Extensions.EventSource/.publicApi/netstandard2.0/PublicAPI.Unshipped.txt

@@ -0,0 +1,4 @@
+#nullable enable
+OpenTelemetry.Logs.OpenTelemetryEventSourceLogEmitter
+OpenTelemetry.Logs.OpenTelemetryEventSourceLogEmitter.OpenTelemetryEventSourceLogEmitter(OpenTelemetry.Logs.OpenTelemetryLoggerProvider! openTelemetryLoggerProvider, System.Func<string!, System.Diagnostics.Tracing.EventLevel?>! shouldListenToFunc, bool disposeProvider = true) -> void
+override OpenTelemetry.Logs.OpenTelemetryEventSourceLogEmitter.Dispose() -> void

src/OpenTelemetry.Extensions.EventSource/.publicApi/netstandard2.1/PublicAPI.Shipped.txt

@@ -0,0 +1 @@
+#nullable enable

src/OpenTelemetry.Extensions.EventSource/.publicApi/netstandard2.1/PublicAPI.Unshipped.txt

@@ -0,0 +1,4 @@
+#nullable enable
+OpenTelemetry.Logs.OpenTelemetryEventSourceLogEmitter
+OpenTelemetry.Logs.OpenTelemetryEventSourceLogEmitter.OpenTelemetryEventSourceLogEmitter(OpenTelemetry.Logs.OpenTelemetryLoggerProvider! openTelemetryLoggerProvider, System.Func<string!, System.Diagnostics.Tracing.EventLevel?>! shouldListenToFunc, bool disposeProvider = true) -> void
+override OpenTelemetry.Logs.OpenTelemetryEventSourceLogEmitter.Dispose() -> void

src/OpenTelemetry.Extensions.EventSource/AssemblyInfo.cs

@@ -0,0 +1,35 @@
+// <copyright file="AssemblyInfo.cs" company="OpenTelemetry Authors">
+// Copyright The OpenTelemetry Authors
+//
+// Licensed 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.
+// </copyright>
+
+using System;
+using System.Runtime.CompilerServices;
+
+[assembly: CLSCompliant(false)]
+[assembly: InternalsVisibleTo("DynamicProxyGenAssembly2" + AssemblyInfo.MoqPublicKey)]
+
+#if SIGNED
+internal static class AssemblyInfo
+{
+    public const string PublicKey = ", PublicKey=002400000480000094000000060200000024000052534131000400000100010051C1562A090FB0C9F391012A32198B5E5D9A60E9B80FA2D7B434C9E5CCB7259BD606E66F9660676AFC6692B8CDC6793D190904551D2103B7B22FA636DCBB8208839785BA402EA08FC00C8F1500CCEF28BBF599AA64FFB1E1D5DC1BF3420A3777BADFE697856E9D52070A50C3EA5821C80BEF17CA3ACFFA28F89DD413F096F898";
+    public const string MoqPublicKey = ", PublicKey=0024000004800000940000000602000000240000525341310004000001000100c547cac37abd99c8db225ef2f6c8a3602f3b3606cc9891605d02baa56104f4cfc0734aa39b93bf7852f7d9266654753cc297e7d2edfe0bac1cdcf9f717241550e0a7b191195b7667bb4f64bcb8e2121380fd1d9d46ad2d92d2d15605093924cceaf74c4861eff62abf69b9291ed0a340e113be11e6a7d3113e92484cf7045cc7";
+}
+#else
+internal static class AssemblyInfo
+{
+    public const string PublicKey = "";
+    public const string MoqPublicKey = "";
+}
+#endif

src/OpenTelemetry.Extensions.EventSource/CHANGELOG.md

@@ -0,0 +1,5 @@
+# Changelog
+
+## Unreleased
+
+Initial release.

src/OpenTelemetry.Extensions.EventSource/OpenTelemetry.Extensions.EventSource.csproj

@@ -0,0 +1,19 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <!-- OmniSharp/VS Code requires TargetFrameworks to be in descending order for IntelliSense and analysis. -->
+    <TargetFrameworks>netstandard2.1;netstandard2.0</TargetFrameworks>
+    <Description>Extensions for using OpenTelemetry with System.Diagnostics.Tracing.EventSource</Description>
+    <Nullable>enable</Nullable>
+    <AnalysisMode>AllEnabledByDefault</AnalysisMode>
+    <AnalysisLevel>latest</AnalysisLevel>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="$(RepoRoot)\src\OpenTelemetry\OpenTelemetry.csproj" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <Compile Include="$(RepoRoot)\src\OpenTelemetry.Api\Internal\Guard.cs" Link="Includes\Guard.cs" />
+  </ItemGroup>
+
+</Project>