From ff1ff4360b104c291c907c62e114513d41f775e0 Mon Sep 17 00:00:00 2001
From: James Newton-King <james@newtonking.com>
Date: Mon, 4 Mar 2024 07:31:54 +0800
Subject: [PATCH] Add configuration of OTLP export endpoint to standalone
 dashboard sample and improve readme (#136)

---
 .../StandaloneDashboard/ConsoleApp/Program.cs   | 11 ++++++++---
 .../ConsoleApp/Properties/launchSettings.json   | 10 ++++++++++
 .../ConsoleApp/appsettings.Development.json     |  7 +++++++
 .../ConsoleApp/appsettings.json                 |  8 ++++++++
 samples/StandaloneDashboard/README.md           | 17 ++++++++++++-----
 5 files changed, 45 insertions(+), 8 deletions(-)
 create mode 100644 samples/StandaloneDashboard/ConsoleApp/Properties/launchSettings.json
 create mode 100644 samples/StandaloneDashboard/ConsoleApp/appsettings.Development.json
 create mode 100644 samples/StandaloneDashboard/ConsoleApp/appsettings.json

diff --git a/samples/StandaloneDashboard/ConsoleApp/Program.cs b/samples/StandaloneDashboard/ConsoleApp/Program.cs
index 794f2df2..67a5bf88 100644
--- a/samples/StandaloneDashboard/ConsoleApp/Program.cs
+++ b/samples/StandaloneDashboard/ConsoleApp/Program.cs
@@ -40,9 +40,14 @@ static IHostApplicationBuilder ConfigureOpenTelemetry(IHostApplicationBuilder bu
             tracing.AddSource(PokemonDownloader.ActivitySourceName);
         });
 
-    builder.Services.Configure<OpenTelemetryLoggerOptions>(logging => logging.AddOtlpExporter());
-    builder.Services.ConfigureOpenTelemetryMeterProvider(metrics => metrics.AddOtlpExporter());
-    builder.Services.ConfigureOpenTelemetryTracerProvider(tracing => tracing.AddOtlpExporter());
+    // Use the OTLP exporter if the endpoint is configured.
+    var useOtlpExporter = !string.IsNullOrWhiteSpace(builder.Configuration["OTEL_EXPORTER_OTLP_ENDPOINT"]);
+    if (useOtlpExporter)
+    {
+        builder.Services.Configure<OpenTelemetryLoggerOptions>(logging => logging.AddOtlpExporter());
+        builder.Services.ConfigureOpenTelemetryMeterProvider(metrics => metrics.AddOtlpExporter());
+        builder.Services.ConfigureOpenTelemetryTracerProvider(tracing => tracing.AddOtlpExporter());
+    }
 
     return builder;
 }
diff --git a/samples/StandaloneDashboard/ConsoleApp/Properties/launchSettings.json b/samples/StandaloneDashboard/ConsoleApp/Properties/launchSettings.json
new file mode 100644
index 00000000..af72d728
--- /dev/null
+++ b/samples/StandaloneDashboard/ConsoleApp/Properties/launchSettings.json
@@ -0,0 +1,10 @@
+{
+  "profiles": {
+    "ConsoleApp": {
+      "commandName": "Project",
+      "environmentVariables": {
+        "DOTNET_ENVIRONMENT": "Development"
+      }
+    }
+  }
+}
\ No newline at end of file
diff --git a/samples/StandaloneDashboard/ConsoleApp/appsettings.Development.json b/samples/StandaloneDashboard/ConsoleApp/appsettings.Development.json
new file mode 100644
index 00000000..dc23838b
--- /dev/null
+++ b/samples/StandaloneDashboard/ConsoleApp/appsettings.Development.json
@@ -0,0 +1,7 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Debug"
+    }
+  }
+}
diff --git a/samples/StandaloneDashboard/ConsoleApp/appsettings.json b/samples/StandaloneDashboard/ConsoleApp/appsettings.json
new file mode 100644
index 00000000..4909257a
--- /dev/null
+++ b/samples/StandaloneDashboard/ConsoleApp/appsettings.json
@@ -0,0 +1,8 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information"
+    }
+  },
+  "OTEL_EXPORTER_OTLP_ENDPOINT": "http://localhost:4317"
+}
diff --git a/samples/StandaloneDashboard/README.md b/samples/StandaloneDashboard/README.md
index 254483d7..88eb9335 100644
--- a/samples/StandaloneDashboard/README.md
+++ b/samples/StandaloneDashboard/README.md
@@ -12,12 +12,15 @@ description: "A sample of using the Aspire dashboard to view telemetry from non-
 
 # Standalone Aspire dashboard sample app
 
-The Aspire dashboard can be used to view OpenTelemetry data from any app. The dashboard supports running standalone, and any app can send it open telemetry.
+View telemetry from any app in the Aspire dashboard. The dashboard supports running standalone, and apps configured with an [OpenTelemetry SDK](https://opentelemetry.io/docs/getting-started/dev/) can send it data.
 
-This is a simple .NET app that downloads data from [PokeAPI](https://pokeapi.co/). The app sends telemetry to the Aspire dashboard which can be viewed in the dashboard telemetry UI.
+This sample is a .NET console app that downloads data from [PokeAPI](https://pokeapi.co/). The app sends telemetry to the Aspire dashboard which is viewed in the dashboard telemetry UI.
 
 ![Screenshot of the standalone .NET Aspire dashboard](./images/aspire-dashboard-screenshot.png)
 
+> [!NOTE]
+> [PokeAPI](https://pokeapi.co/) is a free, open-source RESTful API that is not owned by Microsoft.
+
 ## Demonstrates
 
 - How to run the Aspire dashboard from a Docker container
@@ -66,6 +69,10 @@ dotnet run --project ConsoleApp
 
 1. The console app launches, downloads information about all Pokemon and then exits.
 2. View the Aspire dashboard at http://localhost:18888 to see app telemetry.
-  1. View structured logs to see the list of downloaded Pokemon.
-  2. View traces to see HTTP requests made.
-  3. View metrics to see numeric data about the app such as average HTTP request duration.
+    1. View structured logs to see the list of downloaded Pokemon.
+    2. View traces to see HTTP requests made.
+    3. View metrics to see numeric data about the app such as average HTTP request duration.
+
+## Configure OpenTelemetry
+
+The telemetry export endpoint is configured with the `OTEL_EXPORTER_OTLP_ENDPOINT` setting. This value is set to `http://localhost:4317` in the sample's appsettings.json file. Removing the `OTEL_EXPORTER_OTLP_ENDPOINT` value disables exporting telemetry.