Add support for binding FormatterOptions from config file

src/libraries/Microsoft.Extensions.Logging.EventLog/src/EventLogConfigureOptions.cs

@@ -0,0 +1,31 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System.Runtime.Versioning;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.Logging.Configuration;
+using Microsoft.Extensions.Logging.EventLog;
+using Microsoft.Extensions.Options;
+
+namespace Microsoft.Extensions.Logging
+{
+    /// <summary>
+    /// Configures an EventLogSettings object from an IConfiguration.
+    /// </summary>
+    /// <remarks>
+    /// Uses source-generated configuration binding to allow ConfigurationBinder, and all its dependencies,
+    /// to be trimmed. This improves app size and startup.
+    /// </remarks>
+    internal sealed class EventLogConfigureOptions : IConfigureOptions<EventLogSettings>
+    {
+        private readonly IConfiguration _configuration;
+
+        [UnsupportedOSPlatform("browser")]
+        public EventLogConfigureOptions(ILoggerProviderConfiguration<EventLogLoggerProvider> providerConfiguration)
+        {
+            _configuration = providerConfiguration.Configuration;
+        }
+
+        public void Configure(EventLogSettings options) => _configuration.Bind(options);
+    }
+}

src/libraries/Microsoft.Extensions.Logging.EventLog/src/EventLoggerFactoryExtensions.cs

@@ -5,7 +5,9 @@
 using System.ComponentModel;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.DependencyInjection.Extensions;
+using Microsoft.Extensions.Logging.Configuration;
 using Microsoft.Extensions.Logging.EventLog;
+using Microsoft.Extensions.Options;
 
 namespace Microsoft.Extensions.Logging
 {
@@ -57,7 +59,10 @@ public static ILoggingBuilder AddEventLog(this ILoggingBuilder builder)
         {
             ArgumentNullException.ThrowIfNull(builder);
 
+            builder.AddConfiguration();
             builder.Services.TryAddEnumerable(ServiceDescriptor.Singleton<ILoggerProvider, EventLogLoggerProvider>());
+            builder.Services.TryAddEnumerable(ServiceDescriptor.Singleton<IConfigureOptions<EventLogSettings>, EventLogConfigureOptions>());
+            builder.Services.TryAddEnumerable(ServiceDescriptor.Singleton<IOptionsChangeTokenSource<EventLogSettings>, LoggerProviderOptionsChangeTokenSource<EventLogSettings, EventLogLoggerProvider>>());
 
             return builder;
         }

src/libraries/Microsoft.Extensions.Logging.EventLog/src/Microsoft.Extensions.Logging.EventLog.csproj

@@ -7,6 +7,10 @@
     <PackageDescription>Windows Event Log logger provider implementation for Microsoft.Extensions.Logging.</PackageDescription>
     <!-- TODO: Add package README file: https://github.com/dotnet/runtime/issues/99358 -->
     <EnableDefaultPackageReadmeFile>false</EnableDefaultPackageReadmeFile>
+    <EnableConfigurationBindingGenerator>true</EnableConfigurationBindingGenerator>
+    <InterceptorsPreviewNamespaces>$(InterceptorsPreviewNamespaces);Microsoft.Extensions.Configuration.Binder.SourceGeneration</InterceptorsPreviewNamespaces>
+    <!-- TODO: reinstate pragma suppressions for config binding diagnostics: https://github.com/dotnet/runtime/issues/92509. -->
+    <NoWarn>$(NoWarn);SYSLIB1100;SYSLIB1101</NoWarn>
   </PropertyGroup>
 
   <ItemGroup>
@@ -17,9 +21,14 @@
   </ItemGroup>
 
   <ItemGroup>
+    <ProjectReference Include="$(LibrariesProjectRoot)Microsoft.Extensions.Configuration.Binder\gen\Microsoft.Extensions.Configuration.Binder.SourceGeneration.csproj"
+                      OutputItemType="Analyzer"
+                      ReferenceOutputAssembly="false"
+                      PrivateAssets="all" />
     <ProjectReference Include="$(LibrariesProjectRoot)Microsoft.Extensions.DependencyInjection.Abstractions\src\Microsoft.Extensions.DependencyInjection.Abstractions.csproj" />
     <ProjectReference Include="$(LibrariesProjectRoot)Microsoft.Extensions.Logging\src\Microsoft.Extensions.Logging.csproj" />
     <ProjectReference Include="$(LibrariesProjectRoot)Microsoft.Extensions.Logging.Abstractions\src\Microsoft.Extensions.Logging.Abstractions.csproj" />
+    <ProjectReference Include="$(LibrariesProjectRoot)Microsoft.Extensions.Logging.Configuration\src\Microsoft.Extensions.Logging.Configuration.csproj" />
     <ProjectReference Include="$(LibrariesProjectRoot)Microsoft.Extensions.Options\src\Microsoft.Extensions.Options.csproj" />
   </ItemGroup>
 

src/libraries/Microsoft.Extensions.Logging/tests/Common/EventLogLoggerTest.cs

@@ -5,6 +5,7 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
+using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging.EventLog;
 using Xunit;
@@ -126,6 +127,55 @@ public void IOptions_CreatesWindowsEventLog_WithSuppliedEventLogSettings()
             Assert.Equal("blah", settings.MachineName);
         }
 
+        [Fact]
+        [PlatformSpecific(TestPlatforms.Windows)]
+        public void AddEventLog_SettingsFromConfiguration_IsReadFromLoggingConfiguration()
+        {
+            var configuration = new ConfigurationBuilder().AddInMemoryCollection(new[]
+            {
+                new KeyValuePair<string, string>("Logging:EventLog:SourceName", "TestSource"),
+                new KeyValuePair<string, string>("Logging:EventLog:LogName", "TestLog"),
+                new KeyValuePair<string, string>("Logging:EventLog:MachineName", "TestMachine"),
+            }).Build();
+
+            var serviceCollection = new ServiceCollection();
+            serviceCollection.AddLogging(builder => builder
+                .AddConfiguration(configuration.GetSection("Logging"))
+                .AddEventLog());
+
+            var services = serviceCollection.BuildServiceProvider();
+            var provider = (EventLogLoggerProvider)(services.GetRequiredService<IEnumerable<ILoggerProvider>>().First());
+            var settings = provider._settings;
+            Assert.Equal("TestLog", settings.LogName);
+            Assert.Equal("TestSource", settings.SourceName);
+            Assert.Equal("TestMachine", settings.MachineName);
+        }
+
+        [Fact]
+        [PlatformSpecific(TestPlatforms.Windows)]
+        public void AddEventLog_SettingsFromConfiguration_ActionOverridesConfigValues()
+        {
+            var configuration = new ConfigurationBuilder().AddInMemoryCollection(new[]
+            {
+                new KeyValuePair<string, string>("Logging:EventLog:SourceName", "ConfigSource"),
+                new KeyValuePair<string, string>("Logging:EventLog:LogName", "ConfigLog"),
+            }).Build();
+
+            var serviceCollection = new ServiceCollection();
+            serviceCollection.AddLogging(builder => builder
+                .AddConfiguration(configuration.GetSection("Logging"))
+                .AddEventLog(options =>
+                {
+                    options.SourceName = "ActionSource";
+                }));
+
+            var services = serviceCollection.BuildServiceProvider();
+            var provider = (EventLogLoggerProvider)(services.GetRequiredService<IEnumerable<ILoggerProvider>>().First());
+            var settings = provider._settings;
+            Assert.Equal("ActionSource", settings.SourceName);
+            Assert.Equal("ConfigLog", settings.LogName);
+        }
+
         [Theory]
         [PlatformSpecific(TestPlatforms.Windows)]
         [InlineData(50)]