Improve OTLP observability example: add usings, reorder steps, refresh versions

docs/core/diagnostics/observability-with-otel.md

@@ -91,7 +91,7 @@ The following table describes the main packages.
 
 This topic is continued with a couple of example walkthroughs for using OpenTelemetry in .NET:
 
-- [Example: Use OTLP and the standalone Aspire Dashboard](./observability-otlp-example.md)
+- [Use OTLP and the Aspire Dashboard](./observability-otlp-example.md)
 - [Example: Use OpenTelemetry with Azure Monitor and Application Insights](./observability-applicationinsights.md)
 - [Example: Use OpenTelemetry with Prometheus, Grafana, and Jaeger](./observability-prgrja-example.md)
 

docs/core/diagnostics/snippets/observability-otlp-example/csharp/Program.cs

@@ -0,0 +1,97 @@
+// <Usings>
+using System.Diagnostics;
+using System.Diagnostics.Metrics;
+using OpenTelemetry.Exporter;
+using OpenTelemetry.Logs;
+using OpenTelemetry.Metrics;
+using OpenTelemetry.Resources;
+using OpenTelemetry.Trace;
+// </Usings>
+
+// <CustomMetrics>
+// Custom metrics for the application
+var greeterMeter = new Meter("OTel.Example", "1.0.0");
+var countGreetings = greeterMeter.CreateCounter<int>("greetings.count", description: "Counts the number of greetings");
+
+// Custom ActivitySource for the application
+var greeterActivitySource = new ActivitySource("OTel.Example");
+// </CustomMetrics>
+
+var builder = WebApplication.CreateBuilder(args);
+
+// <OTEL>
+// Configure the shared OTLP connection used by logs, metrics, and traces.
+var otlpEndpoint = new Uri(builder.Configuration["OTEL_EXPORTER_OTLP_ENDPOINT"]!);
+Action<OtlpExporterOptions> configureOtlp = options =>
+{
+    options.Endpoint = otlpEndpoint;
+    options.Protocol = OtlpExportProtocol.Grpc;
+    options.Headers = builder.Configuration["OTEL_EXPORTER_OTLP_HEADERS"]; // To secure endpoint (not in this example)
+};
+
+// Setup logging to be exported via OpenTelemetry
+builder.Logging.AddOpenTelemetry(logging =>
+{
+    logging.IncludeFormattedMessage = true;
+    logging.IncludeScopes = true;
+    logging.AddOtlpExporter(configureOtlp);
+});
+
+var otel = builder.Services.AddOpenTelemetry();
+
+// Identify this application as a single service in the Aspire dashboard.
+otel.ConfigureResource(resource => resource.AddService(builder.Configuration["OTEL_SERVICE_NAME"]!));
+
+// Add Metrics for ASP.NET Core and our custom metrics and export via OTLP
+otel.WithMetrics(metrics =>
+{
+    // Metrics provider from OpenTelemetry
+    metrics.AddAspNetCoreInstrumentation();
+
+    // Our custom metrics
+    metrics.AddMeter(greeterMeter.Name);
+
+    // Metrics provided by ASP.NET Core in .NET
+    metrics.AddMeter("Microsoft.AspNetCore.Hosting");
+    metrics.AddMeter("Microsoft.AspNetCore.Server.Kestrel");
+
+    // Export the metrics via OTLP
+    metrics.AddOtlpExporter(configureOtlp);
+});
+
+// Add Tracing for ASP.NET Core and our custom ActivitySource and export via OTLP
+otel.WithTracing(tracing =>
+{
+    tracing.AddAspNetCoreInstrumentation();
+    tracing.AddHttpClientInstrumentation();
+    tracing.AddSource(greeterActivitySource.Name);
+    tracing.AddOtlpExporter(configureOtlp);
+});
+// </OTEL>
+
+var app = builder.Build();
+
+// <MapGet>
+app.MapGet("/", SendGreeting);
+// </MapGet>
+
+app.Run();
+
+// <SendGreeting>
+async Task<string> SendGreeting(ILogger<Program> logger)
+{
+    // Create a new Activity scoped to the method
+    using var activity = greeterActivitySource.StartActivity("GreeterActivity");
+
+    // Log a message
+    logger.LogInformation("Sending greeting");
+
+    // Increment the custom counter
+    countGreetings.Add(1);
+
+    // Add a tag to the Activity
+    activity?.SetTag("greeting", "Hello World!");
+
+    return "Hello World!";
+}
+// </SendGreeting>

docs/core/diagnostics/snippets/observability-otlp-example/csharp/Properties/launchSettings.json

@@ -0,0 +1,23 @@
+{
+  "$schema": "https://json.schemastore.org/launchsettings.json",
+  "profiles": {
+    "http": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "applicationUrl": "http://localhost:5245",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+    "https": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "applicationUrl": "https://localhost:7147;http://localhost:5245",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    }
+  }
+}

docs/core/diagnostics/snippets/observability-otlp-example/csharp/appsettings.Development.json

@@ -0,0 +1,10 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "OTEL_EXPORTER_OTLP_ENDPOINT": "http://localhost:4317",
+  "OTEL_SERVICE_NAME": "OTLP-Example"
+}

docs/core/diagnostics/snippets/observability-otlp-example/csharp/appsettings.json

@@ -0,0 +1,9 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "AllowedHosts": "*"
+}

docs/core/diagnostics/snippets/observability-otlp-example/csharp/observability-otlp-example.csproj

@@ -0,0 +1,18 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <PropertyGroup>
+    <TargetFramework>net10.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+  <!-- <PackageReferences> -->
+  <ItemGroup>
+    <PackageReference Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.17.0" />
+    <PackageReference Include="OpenTelemetry.Extensions.Hosting" Version="1.17.0" />
+    <PackageReference Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.17.0" />
+    <PackageReference Include="OpenTelemetry.Instrumentation.Http" Version="1.17.0" />
+  </ItemGroup>
+  <!-- </PackageReferences> -->
+
+</Project>

docs/navigate/tools-diagnostics/toc.yml

@@ -408,7 +408,7 @@ items:
         items:
           - name: Overview
             href: ../../core/diagnostics/observability-with-otel.md
-          - name: "Example: Use OpenTelemetry with OTLP and the standalone Aspire Dashboard"
+          - name: "Use OpenTelemetry with OTLP and the Aspire Dashboard"
             href: ../../core/diagnostics/observability-otlp-example.md
           - name: "Example: Use OpenTelemetry with Prometheus, Grafana, and Jaeger"
             href: ../../core/diagnostics/observability-prgrja-example.md