refactor: move AddSerilog to separate class

src/Serilog.Extensions.Hosting/Serilog.Extensions.Hosting.csproj

@@ -1,11 +1,11 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <Description>Serilog support for .NET Core logging in hosted services</Description>
     <VersionPrefix>5.0.1</VersionPrefix>
     <Authors>Microsoft;Serilog Contributors</Authors>
     <TargetFrameworks>netstandard2.0;netstandard2.1;net6.0;net7.0</TargetFrameworks>
-    <LangVersion>8</LangVersion>
+    <LangVersion>latest</LangVersion>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
     <AssemblyName>Serilog.Extensions.Hosting</AssemblyName>

src/Serilog.Extensions.Hosting/SerilogHostBuilderExtensions.cs

@@ -32,7 +32,7 @@ public static class SerilogHostBuilderExtensions
         // root logger, registering it as a singleton may lead to disposal along with the container by MEDI. This isn't
         // always desirable, i.e. we may be handed a logger and `dispose: false`, so wrapping it keeps us in control
         // of when the logger is disposed.
-        private class RegisteredLogger
+        internal class RegisteredLogger
         {
             public RegisteredLogger(ILogger logger)
             {
@@ -64,58 +64,6 @@ public static IHostBuilder UseSerilog(
                 services.AddLogging(logging => logging.AddSerilog(logger, dispose, providers)));
         }
 
-        /// <summary>
-        /// Sets Serilog as the logging provider.
-        /// </summary>
-        /// <param name="builder">The logging builder to configure.</param>
-        /// <param name="logger">The Serilog logger; if not supplied, the static <see cref="Serilog.Log"/> will be used.</param>
-        /// <param name="dispose">When <c>true</c>, dispose <paramref name="logger"/> when the framework disposes the provider. If the
-        /// logger is not specified but <paramref name="dispose"/> is <c>true</c>, the <see cref="Serilog.Log.CloseAndFlush()"/> method will be
-        /// called on the static <see cref="Serilog.Log"/> class instead.</param>
-        /// <param name="providers">A <see cref="LoggerProviderCollection"/> registered in the Serilog pipeline using the
-        /// <c>WriteTo.Providers()</c> configuration method, enabling other <see cref="Microsoft.Extensions.Logging.ILoggerProvider"/>s to receive events. By
-        /// default, only Serilog sinks will receive events.</param>
-        /// <returns>The host builder.</returns>
-        public static ILoggingBuilder AddSerilog(
-            this ILoggingBuilder builder,
-            ILogger logger = null,
-            bool dispose = false,
-            LoggerProviderCollection providers = null)
-        {
-            if (builder == null) throw new ArgumentNullException(nameof(builder));
-
-            var services = builder.Services;
-            if (providers != null)
-            {
-                services.AddSingleton<ILoggerFactory>(services =>
-                {
-                    var factory = new SerilogLoggerFactory(logger, dispose, providers);
-
-                    foreach (var provider in services.GetServices<ILoggerProvider>())
-                        factory.AddProvider(provider);
-
-                    return factory;
-                });
-            }
-            else
-            {
-                services.AddSingleton<ILoggerFactory>(services => new SerilogLoggerFactory(logger, dispose));
-            }
-
-            if (logger != null)
-            {
-                // This won't (and shouldn't) take ownership of the logger.
-                services.AddSingleton(logger);
-
-                // Still need to use RegisteredLogger as it is used by ConfigureDiagnosticContext.
-                services.AddSingleton(new RegisteredLogger(logger));
-            }
-            bool useRegisteredLogger = logger != null;
-            ConfigureDiagnosticContext(services, useRegisteredLogger);
-
-            return builder;
-        }
-
         /// <summary>Sets Serilog as the logging provider.</summary>
         /// <remarks>
         /// A <see cref="HostBuilderContext"/> is supplied so that configuration and hosting information can be used.
@@ -258,7 +206,7 @@ public static IHostBuilder UseSerilog(
             return builder;
         }
 
-        private static void ConfigureDiagnosticContext(IServiceCollection collection, bool useRegisteredLogger)
+        internal static void ConfigureDiagnosticContext(IServiceCollection collection, bool useRegisteredLogger)
         {
             if (collection == null) throw new ArgumentNullException(nameof(collection));
 

src/Serilog.Extensions.Hosting/SerilogLoggingBuilderExtensions.cs

@@ -0,0 +1,65 @@
+using Microsoft.Extensions.DependencyInjection;
+using Serilog.Extensions.Logging;
+using System;
+using static Serilog.SerilogHostBuilderExtensions;
+
+namespace Microsoft.Extensions.Logging
+{
+    /// <summary>
+    /// Extends <see cref="ILoggingBuilder"/> with Serilog configuration methods.
+    /// </summary>
+    public static class SerilogLoggingBuilderExtensions
+    {
+        /// <summary>
+        /// Sets Serilog as the logging provider.
+        /// </summary>
+        /// <param name="builder">The logging builder to configure.</param>
+        /// <param name="logger">The Serilog logger; if not supplied, the static <see cref="Serilog.Log"/> will be used.</param>
+        /// <param name="dispose">When <c>true</c>, dispose <paramref name="logger"/> when the framework disposes the provider. If the
+        /// logger is not specified but <paramref name="dispose"/> is <c>true</c>, the <see cref="Serilog.Log.CloseAndFlush()"/> method will be
+        /// called on the static <see cref="Serilog.Log"/> class instead.</param>
+        /// <param name="providers">A <see cref="LoggerProviderCollection"/> registered in the Serilog pipeline using the
+        /// <c>WriteTo.Providers()</c> configuration method, enabling other <see cref="Microsoft.Extensions.Logging.ILoggerProvider"/>s to receive events. By
+        /// default, only Serilog sinks will receive events.</param>
+        /// <returns>The host builder.</returns>
+        public static ILoggingBuilder AddSerilog(
+            this ILoggingBuilder builder,
+            Serilog.ILogger logger = null,
+            bool dispose = false,
+            LoggerProviderCollection providers = null)
+        {
+            if (builder == null) throw new ArgumentNullException(nameof(builder));
+
+            var services = builder.Services;
+            if (providers != null)
+            {
+                services.AddSingleton<ILoggerFactory>(services =>
+                {
+                    var factory = new SerilogLoggerFactory(logger, dispose, providers);
+
+                    foreach (var provider in services.GetServices<ILoggerProvider>())
+                        factory.AddProvider(provider);
+
+                    return factory;
+                });
+            }
+            else
+            {
+                services.AddSingleton<ILoggerFactory>(services => new SerilogLoggerFactory(logger, dispose));
+            }
+
+            if (logger != null)
+            {
+                // This won't (and shouldn't) take ownership of the logger.
+                services.AddSingleton(logger);
+
+                // Still need to use RegisteredLogger as it is used by ConfigureDiagnosticContext.
+                services.AddSingleton(new RegisteredLogger(logger));
+            }
+            bool useRegisteredLogger = logger != null;
+            ConfigureDiagnosticContext(services, useRegisteredLogger);
+
+            return builder;
+        }
+    }
+}