Update OTEL collector to forward non-project resources (#611)

dotnet · Dec 7, 2024 · 32583d1 · 32583d1
1 parent 0c27e4e
commit 32583d1
Showing 1 changed file with 9 additions and 4 deletions.
diff --git a/.../Metrics/MetricsApp.AppHost/OpenTelemetryCollector/OpenTelemetryCollectorLifecycleHook.cs b/.../Metrics/MetricsApp.AppHost/OpenTelemetryCollector/OpenTelemetryCollectorLifecycleHook.cs
@@ -5,6 +5,8 @@ namespace MetricsApp.AppHost.OpenTelemetryCollector;
 
 internal sealed class OpenTelemetryCollectorLifecycleHook : IDistributedApplicationLifecycleHook
 {
+    private const string OtelExporterOtlpEndpoint = "OTEL_EXPORTER_OTLP_ENDPOINT";
+
     private readonly ILogger<OpenTelemetryCollectorLifecycleHook> _logger;
 
     public OpenTelemetryCollectorLifecycleHook(ILogger<OpenTelemetryCollectorLifecycleHook> logger)
@@ -28,13 +30,16 @@ public Task AfterEndpointsAllocatedAsync(DistributedApplicationModel appModel, C
             return Task.CompletedTask;
         }
 
-        foreach (var resource in appModel.GetProjectResources())
+        foreach (var resource in appModel.Resources)
         {
-            _logger.LogDebug("Forwarding telemetry for {ResourceName} to the collector.", resource.Name);
-
             resource.Annotations.Add(new EnvironmentCallbackAnnotation((EnvironmentCallbackContext context) =>
             {
-                context.EnvironmentVariables["OTEL_EXPORTER_OTLP_ENDPOINT"] = endpoint;
+                if (context.EnvironmentVariables.ContainsKey(OtelExporterOtlpEndpoint))
+                {
+                    _logger.LogDebug("Forwarding telemetry for {ResourceName} to the collector.", resource.Name);
+
+                    context.EnvironmentVariables[OtelExporterOtlpEndpoint] = endpoint;
+                }
             }));
         }