Métricas

IMetricsCollector registra métricas por solicitud: duración, conteos de éxito/fallo y tipos de error.

Implementaciones Built-in

Implementación	Descripción
NoOpMetricsCollector	No hace nada — por defecto si no se registra collector
ConsoleMetricsCollector	Imprime métricas en stdout — útil para desarrollo

IMetricsCollector Personalizado

public class PrometheusMetricsCollector : IMetricsCollector
{
    private static readonly Counter RequestsTotal = Metrics.CreateCounter(
        "mediator_requests_total",
        "Total solicitudes del mediador",
        new CounterConfiguration { LabelNames = new[] { "handler", "success" } });

    private static readonly Histogram RequestDuration = Metrics.CreateHistogram(
        "mediator_request_duration_seconds",
        "Duración de solicitudes del mediador",
        new HistogramConfiguration { LabelNames = new[] { "handler" } });

    public void RecordRequestStarted(string requestName) { }

    public void RecordRequestCompleted(string requestName, TimeSpan duration, bool success, string? errorType)
    {
        RequestsTotal.WithLabels(requestName, success.ToString()).Inc();
        RequestDuration.WithLabels(requestName).Observe(duration.TotalSeconds);
    }

    public void RecordRequestFailed(string requestName, TimeSpan duration, Exception exception)
    {
        RequestsTotal.WithLabels(requestName, "false").Inc();
        RequestDuration.WithLabels(requestName).Observe(duration.TotalSeconds);
    }
}

Registro

builder.Services.AddSingleton<IMetricsCollector, PrometheusMetricsCollector>();