[SDK] Support dependency injection in the GetDefaultResource API (#3798)

* Support dependency injection in the GetDefaultResource API.

* CHANGELOG patch.

* Test tweaks.

Co-authored-by: Cijo Thomas <cijo.thomas@gmail.com>

src/OpenTelemetry.Exporter.Jaeger/Implementation/Process.cs

@@ -23,14 +23,9 @@ namespace OpenTelemetry.Exporter.Jaeger.Implementation
 {
     internal sealed class Process
     {
-        public Process(string serviceName)
-        {
-            this.ServiceName = serviceName;
-        }
+        public string ServiceName { get; set; }
 
-        public string ServiceName { get; internal set; }
-
-        internal Dictionary<string, JaegerTag> Tags { get; set; }
+        public Dictionary<string, JaegerTag> Tags { get; set; }
 
         public override string ToString()
         {
@@ -48,7 +43,7 @@ namespace OpenTelemetry.Exporter.Jaeger.Implementation
             return sb.ToString();
         }
 
-        internal void Write(TProtocol oprot)
+        public void Write(TProtocol oprot)
         {
             oprot.IncrementRecursionDepth();
 

src/OpenTelemetry.Exporter.Jaeger/JaegerExporter.cs

@@ -78,14 +78,12 @@ namespace OpenTelemetry.Exporter
             this.batchWriter = protocolFactory.GetProtocol(this.maxPayloadSizeInBytes * 2);
             this.spanWriter = protocolFactory.GetProtocol(this.maxPayloadSizeInBytes);
 
-            string serviceName = (string)this.ParentProvider.GetDefaultResource().Attributes.FirstOrDefault(
-                pair => pair.Key == ResourceSemanticConventions.AttributeServiceName).Value;
-            this.Process = new Process(serviceName);
+            this.Process = new();
 
             client.Connect();
         }
 
-        internal Process Process { get; set; }
+        internal Process Process { get; }
 
         internal EmitBatchArgs EmitBatchArgs { get; private set; }
 
@@ -156,19 +154,21 @@ namespace OpenTelemetry.Exporter
                 }
             }
 
-            if (serviceName != null)
+            if (!string.IsNullOrWhiteSpace(serviceName))
             {
                 serviceName = string.IsNullOrEmpty(serviceNamespace)
                     ? serviceName
                     : serviceNamespace + "." + serviceName;
             }
-
-            if (!string.IsNullOrEmpty(serviceName))
+            else
             {
-                process.ServiceName = serviceName;
+                serviceName = (string)this.ParentProvider.GetDefaultResource().Attributes.FirstOrDefault(
+                    pair => pair.Key == ResourceSemanticConventions.AttributeServiceName).Value;
             }
 
-            this.Batch = new Batch(this.Process, this.batchWriter);
+            process.ServiceName = serviceName;
+
+            this.Batch = new Batch(process, this.batchWriter);
             if (this.sendUsingEmitBatchArgs)
             {
                 this.EmitBatchArgs = new EmitBatchArgs(this.batchWriter);

src/OpenTelemetry/CHANGELOG.md

@@ -11,7 +11,8 @@
 * Added dependency injection support in the `ResourceBuilder` class and added
   support for loading environment variables from `IConfiguration` for the
   `AddEnvironmentVariableDetector` extension
-  ([#3782](https://github.com/open-telemetry/opentelemetry-dotnet/pull/3782))
+  ([#3782](https://github.com/open-telemetry/opentelemetry-dotnet/pull/3782),
+  [#3798](https://github.com/open-telemetry/opentelemetry-dotnet/pull/3798))
 
 ## 1.4.0-beta.2
 

src/OpenTelemetry/Metrics/MeterProviderSdk.cs

@@ -29,6 +29,7 @@ namespace OpenTelemetry.Metrics
 {
     internal sealed class MeterProviderSdk : MeterProvider
     {
+        internal readonly IServiceProvider ServiceProvider;
         internal readonly IDisposable? OwnedServiceProvider;
         internal int ShutdownCount;
         internal bool Disposed;
@@ -44,6 +45,10 @@ namespace OpenTelemetry.Metrics
             IServiceProvider serviceProvider,
             bool ownsServiceProvider)
         {
+            Debug.Assert(serviceProvider != null, "serviceProvider was null");
+
+            this.ServiceProvider = serviceProvider!;
+
             if (ownsServiceProvider)
             {
                 this.OwnedServiceProvider = serviceProvider as IDisposable;
@@ -52,10 +57,10 @@ namespace OpenTelemetry.Metrics
 
             OpenTelemetrySdkEventSource.Log.MeterProviderSdkEvent("Building MeterProvider.");
 
-            var state = new MeterProviderBuilderState(serviceProvider);
+            var state = new MeterProviderBuilderState(serviceProvider!);
 
             MeterProviderBuilderServiceCollectionHelper.InvokeRegisteredConfigureStateCallbacks(
-                serviceProvider,
+                serviceProvider!,
                 state);
 
             StringBuilder exportersAdded = new StringBuilder();

src/OpenTelemetry/ProviderExtensions.cs

@@ -57,7 +57,23 @@ namespace OpenTelemetry
         /// <returns><see cref="Resource"/>if found otherwise <see cref="Resource.Empty"/>.</returns>
         public static Resource GetDefaultResource(this BaseProvider baseProvider)
         {
-            return ResourceBuilder.CreateDefault().Build();
+            var builder = ResourceBuilder.CreateDefault();
+            builder.ServiceProvider = GetServiceProvider(baseProvider);
+            return builder.Build();
+        }
+
+        internal static IServiceProvider GetServiceProvider(this BaseProvider baseProvider)
+        {
+            if (baseProvider is TracerProviderSdk tracerProviderSdk)
+            {
+                return tracerProviderSdk.ServiceProvider;
+            }
+            else if (baseProvider is MeterProviderSdk meterProviderSdk)
+            {
+                return meterProviderSdk.ServiceProvider;
+            }
+
+            return null;
         }
 
         internal static Action GetObservableInstrumentCollectCallback(this BaseProvider baseProvider)

src/OpenTelemetry/Trace/TracerProviderSdk.cs

@@ -29,6 +29,7 @@ namespace OpenTelemetry.Trace
 {
     internal sealed class TracerProviderSdk : TracerProvider
     {
+        internal readonly IServiceProvider ServiceProvider;
         internal readonly IDisposable? OwnedServiceProvider;
         internal int ShutdownCount;
         internal bool Disposed;
@@ -44,6 +45,10 @@ namespace OpenTelemetry.Trace
             IServiceProvider serviceProvider,
             bool ownsServiceProvider)
         {
+            Debug.Assert(serviceProvider != null, "serviceProvider was null");
+
+            this.ServiceProvider = serviceProvider!;
+
             if (ownsServiceProvider)
             {
                 this.OwnedServiceProvider = serviceProvider as IDisposable;
@@ -52,10 +57,10 @@ namespace OpenTelemetry.Trace
 
             OpenTelemetrySdkEventSource.Log.TracerProviderSdkEvent("Building TracerProvider.");
 
-            var state = new TracerProviderBuilderState(serviceProvider);
+            var state = new TracerProviderBuilderState(serviceProvider!);
 
             TracerProviderBuilderServiceCollectionHelper.InvokeRegisteredConfigureStateCallbacks(
-                serviceProvider,
+                serviceProvider!,
                 state);
 
             StringBuilder processorsAdded = new StringBuilder();

test/Benchmarks/Exporter/JaegerExporterBenchmarks.cs

@@ -51,10 +51,7 @@ namespace Benchmarks.Exporter
             using JaegerExporter exporter = new JaegerExporter(
                 new JaegerExporterOptions(),
                 new TCompactProtocol.Factory(),
-                new NoopJaegerClient())
-            {
-                Process = new Jaeger::OpenTelemetry.Exporter.Jaeger.Implementation.Process("TestService"),
-            };
+                new NoopJaegerClient());
 
             for (int i = 0; i < this.NumberOfBatches; i++)
             {

test/OpenTelemetry.Exporter.Jaeger.Tests/JaegerExporterTests.cs

@@ -20,6 +20,7 @@ using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
 using System.Linq;
+using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using OpenTelemetry.Exporter.Jaeger.Implementation;
 using OpenTelemetry.Exporter.Jaeger.Implementation.Tests;
@@ -185,11 +186,9 @@ namespace OpenTelemetry.Exporter.Jaeger.Tests
             using var jaegerTraceExporter = new JaegerExporter(new JaegerExporterOptions());
             var process = jaegerTraceExporter.Process;
 
-            process.ServiceName = "TestService";
-
             jaegerTraceExporter.SetResourceAndInitializeBatch(Resource.Empty);
 
-            Assert.Equal("TestService", process.ServiceName);
+            Assert.StartsWith("unknown_service:", process.ServiceName);
 
             jaegerTraceExporter.SetResourceAndInitializeBatch(ResourceBuilder.CreateEmpty().AddService("MyService").Build());
 
@@ -251,6 +250,34 @@ namespace OpenTelemetry.Exporter.Jaeger.Tests
             Assert.Null(process.Tags);
         }
 
+        [Fact]
+        public void JaegerTraceExporter_SetResource_UpdatesServiceNameFromIConfiguration()
+        {
+            var tracerProviderBuilder = Sdk.CreateTracerProviderBuilder()
+                .ConfigureServices(services =>
+                {
+                    Dictionary<string, string> configuration = new()
+                    {
+                        ["OTEL_SERVICE_NAME"] = "myservicename",
+                    };
+
+                    services.AddSingleton<IConfiguration>(
+                        new ConfigurationBuilder().AddInMemoryCollection(configuration).Build());
+                });
+
+            var jaegerTraceExporter = new JaegerExporter(new JaegerExporterOptions());
+
+            tracerProviderBuilder.AddExporter(ExportProcessorType.Batch, jaegerTraceExporter);
+
+            using var provider = tracerProviderBuilder.Build();
+
+            var process = jaegerTraceExporter.Process;
+
+            jaegerTraceExporter.SetResourceAndInitializeBatch(Resource.Empty);
+
+            Assert.Equal("myservicename", process.ServiceName);
+        }
+
         [Fact]
         public void JaegerTraceExporter_BuildBatchesToTransmit_FlushedBatch()
         {

test/OpenTelemetry.Exporter.Zipkin.Tests/ZipkinExporterTests.cs

@@ -292,6 +292,42 @@ namespace OpenTelemetry.Exporter.Zipkin.Tests
             Assert.Equal(1, invocations);
         }
 
+        [Fact]
+        public void UpdatesServiceNameFromDefaultResource()
+        {
+            var zipkinExporter = new ZipkinExporter(new ZipkinExporterOptions());
+
+            zipkinExporter.SetLocalEndpointFromResource(Resource.Empty);
+
+            Assert.StartsWith("unknown_service:", zipkinExporter.LocalEndpoint.ServiceName);
+        }
+
+        [Fact]
+        public void UpdatesServiceNameFromIConfiguration()
+        {
+            var tracerProviderBuilder = Sdk.CreateTracerProviderBuilder()
+                .ConfigureServices(services =>
+                {
+                    Dictionary<string, string> configuration = new()
+                    {
+                        ["OTEL_SERVICE_NAME"] = "myservicename",
+                    };
+
+                    services.AddSingleton<IConfiguration>(
+                        new ConfigurationBuilder().AddInMemoryCollection(configuration).Build());
+                });
+
+            var zipkinExporter = new ZipkinExporter(new ZipkinExporterOptions());
+
+            tracerProviderBuilder.AddExporter(ExportProcessorType.Batch, zipkinExporter);
+
+            using var provider = tracerProviderBuilder.Build();
+
+            zipkinExporter.SetLocalEndpointFromResource(Resource.Empty);
+
+            Assert.Equal("myservicename", zipkinExporter.LocalEndpoint.ServiceName);
+        }
+
         [Theory]
         [InlineData(true, false, false)]
         [InlineData(false, false, false)]