Function newMeterProvider

internal/traces/otel.go:149–180

newMeterProvider creates a MeterProvider with dual-mode export: - Pull (Prometheus): always active — exposes metrics via /metrics endpoint for scraping. - Push (OTLP HTTP): opt-in — enabled when OTEL_EXPORTER_OTLP_ENDPOINT is set. Uses the standard OTel env var, so it works automatically with any OT

(ctx context.Context, res *resource.Resource)

//   - Push (OTLP HTTP): opt-in — enabled when OTEL_EXPORTER_OTLP_ENDPOINT is set.
//     Uses the standard OTel env var, so it works automatically with any OTel Collector.
func newMeterProvider(ctx context.Context, res *resource.Resource) (*sdkmetric.MeterProvider, error) {
	// Pull exporter: Prometheus scrape endpoint (always active).
	promExp, err := promexporter.New()
	if err != nil {
		return nil, err
	}

	metricsHandler = promhttp.Handler()

	opts := []sdkmetric.Option{
		sdkmetric.WithResource(res),
		sdkmetric.WithReader(promExp),
	}

	// Push exporter: enabled when an OTLP metrics endpoint is configured.
	// Checks OTEL_EXPORTER_OTLP_METRICS_ENDPOINT (signal-specific) or
	// OTEL_EXPORTER_OTLP_ENDPOINT (generic fallback) per the OTel spec.
	if os.Getenv("OTEL_EXPORTER_OTLP_METRICS_ENDPOINT") != "" || os.Getenv("OTEL_EXPORTER_OTLP_ENDPOINT") != "" {
		otlpExp, err := otlpmetrichttp.New(ctx,
			otlpmetrichttp.WithInsecure(),
		)
		if err != nil {
			return nil, err
		}
		opts = append(opts, sdkmetric.WithReader(sdkmetric.NewPeriodicReader(otlpExp,
			sdkmetric.WithInterval(60*time.Second),
		)))
	}

	meterProvider := sdkmetric.NewMeterProvider(opts...)
	return meterProvider, nil
}

func newLoggerProvider() (*log.LoggerProvider, error) {
	logExporter, err := stdoutlog.New()