BlogDoFT.Libs.Api.OpenTelemetry 1.12.0

BlogDoFT.Libs.Api.OpenTelemetry

Helpers to integrate OpenTelemetry tracing, metrics and logs into ASP.NET Core APIs.

This library provides opinionated wiring and small helpers to capture common HTTP server telemetry, plus configuration mapping from IConfiguration so you can control exporters and instrumentations from appsettings.json.

Features

• Easy registration of OpenTelemetry tracing, metrics and logs via a single AddOtel extension method
• Configuration object model that maps to IConfiguration (see sample appsettings.json below)
• Automatic registration of exporters (Console / Zipkin / OTLP / Prometheus) based on configuration

Quick start

1. Reference the package in your Web API project.
2. In Program.cs or Startup.cs, call the extension methods:

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddOtel(builder.Configuration);

var app = builder.Build();
app.UseOpenTelemetry();

app.Run();

Configuration (appsettings.json)

The library reads an Observability section from IConfiguration. Minimal example enabling console tracing and metrics:

{
	"ApplicationName": "MyWebApi",
	"Observability": {
		"OpenTelemetry": {
			"IncludeFormattedMessage": true,
			"IncludeScopes": true,
			"ParseStateValues": true,
			"UseTracingExporter": "Console",
			"UseMetricsExporter": "Console",
			"UseLogExporter": "Console",
			"HistogramAggregation": "ExplicitBounds"
		}
	}
}

Enabling Zipkin exporter:

{
	"Observability": {
		"OpenTelemetry": {
			"UseTracingExporter": "Zipkin"
		},
		"ZipkinExporterOptions": {
			"Endpoint": "http://localhost:9411/api/v2/spans"
		}
	}
}

Enabling OTLP exporter (gRPC):

{
	"Observability": {
		"OpenTelemetry": {
			"UseTracingExporter": "Otlp",
			"UseMetricsExporter": "Otlp"
		},
		"OtlpExporterOptions": {
			"Endpoint": "http://otel-collector:4317",
			"Protocol": "Grpc"
		}
	}
}

Prometheus metrics

To enable Prometheus scraping endpoint set the metrics exporter to Prometheus and (optionally) configure PrometheusAspNetCoreOptions.

Notes

• The library maps configuration into the Observability object model. See the Observability and nested classes for all available fields and defaults.
• When using OTLP, the default endpoint is http://localhost:4317 and default protocol is gRPC.