Add better documentation for IResourceDetector and OltpExporter configuration

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/README.md

@@ -67,7 +67,14 @@ and environment variables.
 The `OtlpExporterOptions` type setters take precedence over the environment variables.
 
 This can be achieved by providing an `Action<OtlpExporterOptions>` delegate to the
-`AddOtlpExporter()` method.
+`AddOtlpExporter()` method or using `AddOptions<OtlpExporterOptions>()`.
+
+If additional services from the dependency injection are required, they can be configured like this:
+```csharp
+services.AddOptions<OtlpExporterOptions>().Configure<Service>((opts, svc) => {
+    // ...
+});
+```
 
 TODO: Show metrics specific configuration (i.e MetricReaderOptions).
 

src/OpenTelemetry.Extensions.Hosting/CHANGELOG.md

@@ -5,6 +5,9 @@
 * Removed deprecated extensions: `AddOpenTelemetryTracing`,
   `AddOpenTelemetryMetrics`, `Configure`, & `GetServices`.
   ([#4071](https://github.com/open-telemetry/opentelemetry-dotnet/pull/4071))
+* Added optional IServiceProvider arguments to the callbacks
+  of `ConfigureResource`, `WithTracing`, & `WithMetrics`.
+  ([#4230](https://github.com/open-telemetry/opentelemetry-dotnet/pull/4230))
 
 ## 1.4.0-rc.4
 

src/OpenTelemetry.Extensions.Hosting/README.md

@@ -83,6 +83,28 @@ app.Run();
 A fully functional example can be found
 [here](https://github.com/open-telemetry/opentelemetry-dotnet/tree/main/examples/AspNetCore).
 
+### Resources
+To dynamically add resources at startup from the dependency injection you can provide an `IResourceDetector`.
+To make use of it add it to the dependency injection and they you can use the `ISerivceProvider` add it to OpenTelemetry:
+```csharp
+public class MyResourceDetector : IResourceDetector
+{
+    public Resource Detect()
+    {
+        return ResourceBuilder.CreateEmpty()
+            .AddService("your service name")
+            .Build();
+    }
+}
+
+services.AddSingleton<MyResourceDetector>();
+
+services.AddOpenTelemetry()
+    .ConfigureResource(builder =>
+        builder.AddDetector(sp => sp!.GetRequiredService<MyResourceDetector>()))
+    WithTracing(builder => builder.AddConsoleExporter());
+```
+
 ## Migrating from pre-release versions of OpenTelemetry.Extensions.Hosting
 
 Pre-release versions (all versions prior to 1.4.0) of

src/OpenTelemetry/.publicApi/net462/PublicAPI.Unshipped.txt

@@ -28,3 +28,4 @@ static OpenTelemetry.Metrics.MeterProviderBuilderExtensions.ConfigureResource(th
 static OpenTelemetry.Trace.TracerProviderBuilderExtensions.ConfigureResource(this OpenTelemetry.Trace.TracerProviderBuilder! tracerProviderBuilder, System.Action<OpenTelemetry.Resources.ResourceBuilder!>! configure) -> OpenTelemetry.Trace.TracerProviderBuilder!
 OpenTelemetry.Metrics.MetricType.LongSumNonMonotonic = 138 -> OpenTelemetry.Metrics.MetricType
 OpenTelemetry.Metrics.MetricType.DoubleSumNonMonotonic = 141 -> OpenTelemetry.Metrics.MetricType
+OpenTelemetry.Resources.ResourceBuilder.AddDetector(System.Func<IServiceProvider, IResourceDetector!>! resourceDetectorFactory) -> OpenTelemetry.Resources.ResourceBuilder!

src/OpenTelemetry/.publicApi/net6.0/PublicAPI.Unshipped.txt

@@ -28,3 +28,4 @@ static OpenTelemetry.Metrics.MeterProviderBuilderExtensions.ConfigureResource(th
 static OpenTelemetry.Trace.TracerProviderBuilderExtensions.ConfigureResource(this OpenTelemetry.Trace.TracerProviderBuilder! tracerProviderBuilder, System.Action<OpenTelemetry.Resources.ResourceBuilder!>! configure) -> OpenTelemetry.Trace.TracerProviderBuilder!
 OpenTelemetry.Metrics.MetricType.LongSumNonMonotonic = 138 -> OpenTelemetry.Metrics.MetricType
 OpenTelemetry.Metrics.MetricType.DoubleSumNonMonotonic = 141 -> OpenTelemetry.Metrics.MetricType
+OpenTelemetry.Resources.ResourceBuilder.AddDetector(System.Func<IServiceProvider, IResourceDetector!>! resourceDetectorFactory) -> OpenTelemetry.Resources.ResourceBuilder!

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

@@ -28,3 +28,4 @@ static OpenTelemetry.Metrics.MeterProviderBuilderExtensions.ConfigureResource(th
 static OpenTelemetry.Trace.TracerProviderBuilderExtensions.ConfigureResource(this OpenTelemetry.Trace.TracerProviderBuilder! tracerProviderBuilder, System.Action<OpenTelemetry.Resources.ResourceBuilder!>! configure) -> OpenTelemetry.Trace.TracerProviderBuilder!
 OpenTelemetry.Metrics.MetricType.LongSumNonMonotonic = 138 -> OpenTelemetry.Metrics.MetricType
 OpenTelemetry.Metrics.MetricType.DoubleSumNonMonotonic = 141 -> OpenTelemetry.Metrics.MetricType
+OpenTelemetry.Resources.ResourceBuilder.AddDetector(System.Func<IServiceProvider, IResourceDetector!>! resourceDetectorFactory) -> OpenTelemetry.Resources.ResourceBuilder!

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

@@ -28,3 +28,4 @@ static OpenTelemetry.Metrics.MeterProviderBuilderExtensions.ConfigureResource(th
 static OpenTelemetry.Trace.TracerProviderBuilderExtensions.ConfigureResource(this OpenTelemetry.Trace.TracerProviderBuilder! tracerProviderBuilder, System.Action<OpenTelemetry.Resources.ResourceBuilder!>! configure) -> OpenTelemetry.Trace.TracerProviderBuilder!
 OpenTelemetry.Metrics.MetricType.LongSumNonMonotonic = 138 -> OpenTelemetry.Metrics.MetricType
 OpenTelemetry.Metrics.MetricType.DoubleSumNonMonotonic = 141 -> OpenTelemetry.Metrics.MetricType
+OpenTelemetry.Resources.ResourceBuilder.AddDetector(System.Func<IServiceProvider, IResourceDetector!>! resourceDetectorFactory) -> OpenTelemetry.Resources.ResourceBuilder!

src/OpenTelemetry/Resources/ResourceBuilder.cs

@@ -142,8 +142,7 @@ public ResourceBuilder AddDetector(IResourceDetector resourceDetector)
         /// </remarks>
         /// <param name="resourceDetectorFactory">Resource detector factory.</param>
         /// <returns>Supplied <see cref="ResourceBuilder"/> for call chaining.</returns>
-        // Note: This API may be made public if there is a need for it.
-        internal ResourceBuilder AddDetector(Func<IServiceProvider?, IResourceDetector> resourceDetectorFactory)
+        public ResourceBuilder AddDetector(Func<IServiceProvider?, IResourceDetector> resourceDetectorFactory)
         {
             Guard.ThrowIfNull(resourceDetectorFactory);
 

src/OpenTelemetry/Trace/Builder/TracerProviderBuilderBase.cs

@@ -41,7 +41,8 @@ public TracerProviderBuilderBase()
             .AddOpenTelemetrySharedProviderBuilderServices()
             .AddOpenTelemetryTracerProviderBuilderServices()
             .TryAddSingleton<TracerProvider>(
-                sp => throw new NotSupportedException("Self-contained TracerProvider cannot be accessed using the application IServiceProvider call Build instead."));
+                sp => throw new NotSupportedException(
+                    "Self-contained TracerProvider cannot be accessed using the application IServiceProvider call Build instead."));
 
         services.ConfigureOpenTelemetryTracerProvider((sp, builder) => this.services = null);
 
@@ -69,7 +70,8 @@ internal TracerProviderBuilderBase(IServiceCollection services)
     TracerProvider? ITracerProviderBuilder.Provider => null;
 
     /// <inheritdoc />
-    public override TracerProviderBuilder AddInstrumentation<TInstrumentation>(Func<TInstrumentation> instrumentationFactory)
+    public override TracerProviderBuilder AddInstrumentation<TInstrumentation>(
+        Func<TInstrumentation> instrumentationFactory)
     {
         Guard.ThrowIfNull(instrumentationFactory);
 
@@ -112,7 +114,8 @@ TracerProviderBuilder ITracerProviderBuilder.ConfigureServices(Action<IServiceCo
         => this.ConfigureServicesInternal(configure);
 
     /// <inheritdoc />
-    TracerProviderBuilder IDeferredTracerProviderBuilder.Configure(Action<IServiceProvider, TracerProviderBuilder> configure)
+    TracerProviderBuilder IDeferredTracerProviderBuilder.Configure(
+        Action<IServiceProvider, TracerProviderBuilder> configure)
         => this.ConfigureBuilderInternal(configure);
 
     internal TracerProvider InvokeBuild()
@@ -154,7 +157,8 @@ protected TracerProvider Build()
     {
         if (!this.allowBuild)
         {
-            throw new NotSupportedException("A TracerProviderBuilder bound to external service cannot be built directly. Access the TracerProvider using the application IServiceProvider instead.");
+            throw new NotSupportedException(
+                "A TracerProviderBuilder bound to external service cannot be built directly. Access the TracerProvider using the application IServiceProvider instead.");
         }
 
         var services = this.services;

src/OpenTelemetry/Trace/Builder/TracerProviderBuilderExtensions.cs

@@ -165,6 +165,28 @@ public static TracerProviderBuilder ConfigureResource(this TracerProviderBuilder
             return tracerProviderBuilder;
         }
 
+        /// <summary>
+        /// Modify the <see cref="ResourceBuilder"/> from which the Resource associated with
+        /// this provider is built from in-place.
+        /// </summary>
+        /// <param name="tracerProviderBuilder"><see cref="TracerProviderBuilder"/>.</param>
+        /// <param name="configure">An action which modifies the provided <see cref="ResourceBuilder"/> in-place.</param>
+        /// <returns>Returns <see cref="TracerProviderBuilder"/> for chaining.</returns>
+        public static TracerProviderBuilder ConfigureResource(this TracerProviderBuilder tracerProviderBuilder, Action<IServiceProvider, ResourceBuilder> configure)
+        {
+            Guard.ThrowIfNull(configure);
+
+            tracerProviderBuilder.ConfigureBuilder((sp, builder) =>
+            {
+                if (builder is TracerProviderBuilderSdk tracerProviderBuilderSdk)
+                {
+                    tracerProviderBuilderSdk.ConfigureResource(traceBuilder => configure(sp, traceBuilder));
+                }
+            });
+
+            return tracerProviderBuilder;
+        }
+
         /// <summary>
         /// Adds a processor to the provider.
         /// </summary>