Remove Prometheus commented out code that does not work (#4096)

* Remove Prometheus commented out code that does not work

* Update Extensions.cs

* Update Extensions.cs

* Update src/Aspire.ProjectTemplates/templates/aspire-empty/AspireApplication.1.ServiceDefaults/Extensions.cs

* Update Extensions.cs

* Update Extensions.cs

* Update Extensions.cs

* Apply suggestions from code review

Co-authored-by: James Newton-King <[email protected]>

* Apply suggestions from code review

---------

Co-authored-by: Sam Spencer <[email protected]>
Co-authored-by: James Newton-King <[email protected]>

Author: 3 people

src/Aspire.ProjectTemplates/templates/aspire-empty/AspireApplication.1.ServiceDefaults/Extensions.cs

@@ -9,6 +9,9 @@
 
 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 IHostApplicationBuilder AddServiceDefaults(this IHostApplicationBuilder builder)
@@ -68,10 +71,6 @@ private static IHostApplicationBuilder AddOpenTelemetryExporters(this IHostAppli
             builder.Services.AddOpenTelemetry().UseOtlpExporter();
         }
 
-        // Uncomment the following lines to enable the Prometheus exporter (requires the OpenTelemetry.Exporter.Prometheus.AspNetCore package)
-        // builder.Services.AddOpenTelemetry()
-        //    .WithMetrics(metrics => metrics.AddPrometheusExporter());
-
         // 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"]))
         //{
@@ -105,9 +104,6 @@ public static WebApplication MapDefaultEndpoints(this WebApplication app)
             {
                 Predicate = r => r.Tags.Contains("live")
             });
-
-            // Uncomment the following line to enable the Prometheus endpoint (requires the OpenTelemetry.Exporter.Prometheus.AspNetCore package)
-            // app.MapPrometheusScrapingEndpoint();
         }
 
         return app;

src/Aspire.ProjectTemplates/templates/aspire-servicedefaults/Extensions.cs

@@ -10,6 +10,9 @@
 
 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 IHostApplicationBuilder AddServiceDefaults(this IHostApplicationBuilder builder)
@@ -75,10 +78,6 @@ private static IHostApplicationBuilder AddOpenTelemetryExporters(this IHostAppli
             builder.Services.AddOpenTelemetry().UseOtlpExporter();
         }
 
-        // Uncomment the following lines to enable the Prometheus exporter (requires the OpenTelemetry.Exporter.Prometheus.AspNetCore package)
-        // builder.Services.AddOpenTelemetry()
-        //    .WithMetrics(metrics => metrics.AddPrometheusExporter());
-
         // 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"]))
         //{
@@ -100,9 +99,6 @@ public static IHostApplicationBuilder AddDefaultHealthChecks(this IHostApplicati
 
     public static WebApplication MapDefaultEndpoints(this WebApplication app)
     {
-        // Uncomment the following line to enable the Prometheus endpoint (requires the OpenTelemetry.Exporter.Prometheus.AspNetCore package)
-        // app.MapPrometheusScrapingEndpoint();
-
         // 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())

src/Aspire.ProjectTemplates/templates/aspire-starter/AspireStarterApplication.1.ServiceDefaults/Extensions.cs

@@ -9,6 +9,9 @@
 
 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 IHostApplicationBuilder AddServiceDefaults(this IHostApplicationBuilder builder)
@@ -68,10 +71,6 @@ private static IHostApplicationBuilder AddOpenTelemetryExporters(this IHostAppli
             builder.Services.AddOpenTelemetry().UseOtlpExporter();
         }
 
-        // Uncomment the following lines to enable the Prometheus exporter (requires the OpenTelemetry.Exporter.Prometheus.AspNetCore package)
-        // builder.Services.AddOpenTelemetry()
-        //    .WithMetrics(metrics => metrics.AddPrometheusExporter());
-
         // 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"]))
         //{
@@ -93,9 +92,6 @@ public static IHostApplicationBuilder AddDefaultHealthChecks(this IHostApplicati
 
     public static WebApplication MapDefaultEndpoints(this WebApplication app)
     {
-        // Uncomment the following line to enable the Prometheus endpoint (requires the OpenTelemetry.Exporter.Prometheus.AspNetCore package)
-        // app.MapPrometheusScrapingEndpoint();
-
         // 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())