Change OTLP endpoint to use HTTP (#735)

Refactor the .NET example to detect #734.

Resolves #734.

---------

Signed-off-by: Martin Costello <martin@martincostello.com>

Author: martincostello

examples/dotnet/Program.cs

@@ -1,5 +1,5 @@
+using OpenTelemetry;
 using OpenTelemetry.Instrumentation.AspNetCore;
-using OpenTelemetry.Logs;
 using OpenTelemetry.Metrics;
 using OpenTelemetry.Resources;
 using OpenTelemetry.Trace;
@@ -13,12 +13,11 @@
     serviceVersion: typeof(Program).Assembly.GetName().Version?.ToString() ?? "unknown",
     serviceInstanceId: Environment.MachineName);
 
-const string DefaultEndpoint = "http://127.0.0.1:4317";
-
 // Configure OpenTelemetry tracing and metrics with auto-start using the
 // AddOpenTelemetry() extension method from the OpenTelemetry.Extensions.Hosting package.
 appBuilder.Services.AddOpenTelemetry()
     .ConfigureResource(configureResource)
+    .UseOtlpExporter()
     .WithTracing(builder =>
     {
         builder
@@ -28,26 +27,12 @@
         // Use IConfiguration binding for AspNetCore instrumentation options.
         appBuilder.Services.Configure<AspNetCoreTraceInstrumentationOptions>(
             appBuilder.Configuration.GetSection("AspNetCoreInstrumentation"));
-
-        builder.AddOtlpExporter(otlpOptions =>
-        {
-            // Use IConfiguration directly for OTLP exporter endpoint option.
-            otlpOptions.Endpoint = new Uri(
-                appBuilder.Configuration.GetValue("Otlp:Endpoint", defaultValue: DefaultEndpoint)!);
-        });
     })
     .WithMetrics(builder =>
     {
         builder
             .AddHttpClientInstrumentation()
             .AddAspNetCoreInstrumentation();
-
-        builder.AddOtlpExporter(otlpOptions =>
-        {
-            // Use IConfiguration directly for OTLP exporter endpoint option.
-            otlpOptions.Endpoint = new Uri(
-                appBuilder.Configuration.GetValue("Otlp:Endpoint", defaultValue: DefaultEndpoint)!);
-        });
     });
 
 // Clear default logging providers used by WebApplication host.
@@ -60,13 +45,6 @@
     var resourceBuilder = ResourceBuilder.CreateDefault();
     configureResource(resourceBuilder);
     options.SetResourceBuilder(resourceBuilder);
-
-    options.AddOtlpExporter(otlpOptions =>
-    {
-        // Use IConfiguration directly for OTLP exporter endpoint option.
-        otlpOptions.Endpoint = new Uri(
-            appBuilder.Configuration.GetValue("Otlp:Endpoint", defaultValue: DefaultEndpoint)!);
-    });
 });
 
 var app = appBuilder.Build();

examples/dotnet/appsettings.json

@@ -21,8 +21,5 @@
         "Url": "http://+:8083"
       }
     }
-  },
-  "Otlp": {
-    "Endpoint": "http://127.0.0.1:4317"
   }
 }

examples/dotnet/docker-compose.oats.yml

@@ -8,5 +8,6 @@ services:
     ports:
       - 8080:8083
     environment:
-      - Otlp__Endpoint=http://lgtm:4317
+      - OTEL_EXPORTER_OTLP_ENDPOINT=http://lgtm:4318
+      - OTEL_EXPORTER_OTLP_PROTOCOL=http/protobuf
       - OTEL_METRIC_EXPORT_INTERVAL=5000 # so we don't have to wait 60s for metrics

examples/dotnet/docker-compose.yml

@@ -8,7 +8,8 @@ services:
     ports:
       - 8083:8083
     environment:
-      - Otlp__Endpoint=http://otel-lgtm:4317
+      - OTEL_EXPORTER_OTLP_ENDPOINT=http://lgtm:4318
+      - OTEL_EXPORTER_OTLP_PROTOCOL=http/protobuf
       - OTEL_METRIC_EXPORT_INTERVAL=5000 # so we don't have to wait 60s for metrics
     depends_on:
       - otel-lgtm