File: Extensions.cs
Web Access
Project: src\playground\Playground.ServiceDefaults\Playground.ServiceDefaults.csproj (Playground.ServiceDefaults)
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Diagnostics.HealthChecks;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Diagnostics.HealthChecks;
using Microsoft.Extensions.Logging;
using OpenTelemetry;
using OpenTelemetry.Metrics;
using OpenTelemetry.Trace;
 
namespace Microsoft.Extensions.Hosting;
 
// Adds common .NET Aspire services: service discovery, resilience, health checks, and OpenTelemetry.
// This project should be referenced by each service project in your solution.
// To learn more about using this project, see https://aka.ms/dotnet/aspire/service-defaults
public static class Extensions
{
    public static TBuilder AddServiceDefaults<TBuilder>(this TBuilder builder) where TBuilder : IHostApplicationBuilder
    {
        builder.ConfigureOpenTelemetry();
 
        builder.AddDefaultHealthChecks();
 
        builder.Services.AddServiceDiscovery();
 
        builder.Services.ConfigureHttpClientDefaults(http =>
        {
            // Turn on resilience by default
            http.AddStandardResilienceHandler();
 
            // Turn on service discovery by default
            http.AddServiceDiscovery();
        });
 
        return builder;
    }
 
    public static TBuilder ConfigureOpenTelemetry<TBuilder>(this TBuilder builder) where TBuilder : IHostApplicationBuilder
    {
        builder.Logging.AddOpenTelemetry(logging =>
        {
            logging.IncludeFormattedMessage = true;
            logging.IncludeScopes = true;
        });
 
        builder.Services.AddOpenTelemetry()
            .WithMetrics(metrics =>
            {
                metrics.AddAspNetCoreInstrumentation()
                    .AddHttpClientInstrumentation()
                    .AddRuntimeInstrumentation();
            })
            .WithTracing(tracing =>
            {
                tracing.AddAspNetCoreInstrumentation()
                    // Uncomment the following line to enable gRPC instrumentation (requires the OpenTelemetry.Instrumentation.GrpcNetClient package)
                    //.AddGrpcClientInstrumentation()
                    .AddHttpClientInstrumentation();
            });
 
        builder.AddOpenTelemetryExporters();
 
        return builder;
    }
 
    private static TBuilder AddOpenTelemetryExporters<TBuilder>(this TBuilder builder) where TBuilder : IHostApplicationBuilder
    {
        var useOtlpExporter = !string.IsNullOrWhiteSpace(builder.Configuration["OTEL_EXPORTER_OTLP_ENDPOINT"]);
 
        if (useOtlpExporter)
        {
            builder.Services.AddOpenTelemetry().UseOtlpExporter();
        }
 
        // Uncomment the following lines to enable the Azure Monitor exporter (requires the Azure.Monitor.OpenTelemetry.AspNetCore package)
        //if (!string.IsNullOrEmpty(builder.Configuration["APPLICATIONINSIGHTS_CONNECTION_STRING"]))
        //{
        //    builder.Services.AddOpenTelemetry()
        //       .UseAzureMonitor();
        //}
 
        return builder;
    }
 
    public static TBuilder AddDefaultHealthChecks<TBuilder>(this TBuilder builder) where TBuilder : IHostApplicationBuilder
    {
        builder.Services.AddHealthChecks()
            // Add a default liveness check to ensure app is responsive
            .AddCheck("self", () => HealthCheckResult.Healthy(), ["live"]);
 
        return builder;
    }
 
    public static WebApplication MapDefaultEndpoints(this WebApplication app)
    {
        // Adding health checks endpoints to applications in non-development environments has security implications.
        // See https://aka.ms/dotnet/aspire/healthchecks for details before enabling these endpoints in non-development environments.
        if (app.Environment.IsDevelopment())
        {
            // All health checks must pass for app to be considered ready to accept traffic after starting
            app.MapHealthChecks("/health");
 
            // Only health checks tagged with the "live" tag must pass for app to be considered alive
            app.MapHealthChecks("/alive", new HealthCheckOptions
            {
                Predicate = r => r.Tags.Contains("live")
            });
        }
 
        return app;
    }
}