[logs-branch] Apply Resource dependency injection pattern to LoggerProvider (#3813)

* Apply resource dependency injection changes to LoggerProvider.

* CHANGELOG update.

* Test update.

* CHANGELOG patch.

src/OpenTelemetry/CHANGELOG.md

@@ -5,6 +5,11 @@
 * Added `LoggerProvider` API from the OpenTelemetry specification
   ([#3707](https://github.com/open-telemetry/opentelemetry-dotnet/pull/3707))
 
+* Added dependency injection support in the `ResourceBuilder` class and added
+  support for loading environment variables from `IConfiguration` for the
+  `AddEnvironmentVariableDetector` extension when using `LoggerProvider`
+  ([#3813](https://github.com/open-telemetry/opentelemetry-dotnet/pull/3813))
+
 ## Unreleased
 
 * Added support for loading environment variables from `IConfiguration` when

src/OpenTelemetry/Logs/LoggerProviderSdk.cs

@@ -21,7 +21,6 @@ using System.Collections.Generic;
 using System.Diagnostics;
 using System.Text;
 using System.Threading;
-using Microsoft.Extensions.DependencyInjection;
 using OpenTelemetry.Internal;
 using OpenTelemetry.Resources;
 
@@ -37,7 +36,8 @@ namespace OpenTelemetry.Logs;
 /// </summary>
 internal sealed class LoggerProviderSdk : LoggerProvider
 {
-    private readonly ServiceProvider? ownedServiceProvider;
+    internal readonly IServiceProvider ServiceProvider;
+    private readonly IDisposable? ownedServiceProvider;
     private readonly List<object> instrumentations = new();
     private ILogRecordPool? threadStaticPool = LogRecordThreadStaticPool.Instance;
     private int shutdownCount;
@@ -47,22 +47,30 @@ internal sealed class LoggerProviderSdk : LoggerProvider
         IServiceProvider serviceProvider,
         bool ownsServiceProvider)
     {
+        Debug.Assert(serviceProvider != null, "serviceProvider was null");
+
         OpenTelemetrySdkEventSource.Log.LoggerProviderSdkEvent("Building LoggerProviderSdk.");
 
+        this.ServiceProvider = serviceProvider!;
+
         if (ownsServiceProvider)
         {
-            this.ownedServiceProvider = serviceProvider as ServiceProvider;
+            this.ownedServiceProvider = serviceProvider as IDisposable;
 
             Debug.Assert(this.ownedServiceProvider != null, "ownedServiceProvider was null");
         }
 
-        var state = new LoggerProviderBuilderState(serviceProvider);
+        var state = new LoggerProviderBuilderState(serviceProvider!);
         state.RegisterProvider(nameof(LoggerProvider), this);
 
         CallbackHelper.InvokeRegisteredConfigureStateCallbacks(
-            serviceProvider,
+            serviceProvider!,
             state);
 
+        var resourceBuilder = state.ResourceBuilder ?? ResourceBuilder.CreateDefault();
+        resourceBuilder.ServiceProvider = serviceProvider;
+        this.Resource = resourceBuilder.Build();
+
         foreach (var processor in state.Processors)
         {
             this.AddProcessor(processor);
@@ -73,8 +81,6 @@ internal sealed class LoggerProviderSdk : LoggerProvider
             this.instrumentations.Add(instrumentation.Instance);
         }
 
-        this.Resource = (state.ResourceBuilder ?? ResourceBuilder.CreateDefault()).Build();
-
         OpenTelemetrySdkEventSource.Log.LoggerProviderSdkEvent("LoggerProviderSdk built successfully.");
     }
 

src/OpenTelemetry/ProviderExtensions.cs

@@ -78,6 +78,10 @@ namespace OpenTelemetry
             {
                 return meterProviderSdk.ServiceProvider;
             }
+            else if (baseProvider is LoggerProviderSdk loggerProviderSdk)
+            {
+                return loggerProviderSdk.ServiceProvider;
+            }
 
             return null;
         }

test/OpenTelemetry.Tests/Logs/OpenTelemetryLoggingExtensionsTests.cs

@@ -415,6 +415,8 @@ public sealed class OpenTelemetryLoggingExtensionsTests
     {
         var services = new ServiceCollection();
 
+        bool serviceProviderTestExecuted = false;
+
         services.AddLogging(builder =>
         {
             builder.AddOpenTelemetry().SetResourceBuilder(ResourceBuilder.CreateDefault().AddService("Examples.LoggingExtensions"));
@@ -427,7 +429,15 @@ public sealed class OpenTelemetryLoggingExtensionsTests
 
         services.ConfigureOpenTelemetryLogging(options =>
         {
-            options.ConfigureResource(builder => builder.AddAttributes(new Dictionary<string, object> { ["key2"] = "value2" }));
+            options.ConfigureResource(builder =>
+            {
+                builder.AddDetector(sp =>
+                {
+                    serviceProviderTestExecuted = true;
+                    Assert.NotNull(sp);
+                    return new ResourceBuilder.WrapperResourceDetector(new Resource(new Dictionary<string, object>() { ["key2"] = "value2" }));
+                });
+            });
         });
 
         using var serviceProvider = services.BuildServiceProvider();
@@ -437,6 +447,7 @@ public sealed class OpenTelemetryLoggingExtensionsTests
         var provider = serviceProvider.GetRequiredService<LoggerProvider>() as LoggerProviderSdk;
 
         Assert.NotNull(provider);
+        Assert.True(serviceProviderTestExecuted);
 
         var resource = provider!.Resource;