beholder: apply 1s MetricReaderInterval default when config field is zero

pkg/beholder/client.go

@@ -434,7 +434,7 @@ func createConfigMetric(meter otelmetric.Meter, cfg Config) (otelmetric.Int64Gau
 
 		// Metrics config
 		attribute.String(
-			"metric_reader_interval", cfg.MetricReaderInterval.String()),
+			"metric_reader_interval", metricReaderInterval(cfg).String()),
 		attribute.String(
 			"metric_compressor", cfg.MetricCompressor),
 	}
@@ -544,7 +544,7 @@ func newMeterProvider(cfg Config, resource *sdkresource.Resource, auth Auth, cre
 	}
 
 	readerOpts := []sdkmetric.PeriodicReaderOption{
-		sdkmetric.WithInterval(cfg.MetricReaderInterval), // Default is 10s
+		sdkmetric.WithInterval(metricReaderInterval(cfg)), // Zero uses Beholder default (1s)
 	}
 	for _, p := range cfg.MetricProducers {
 		readerOpts = append(readerOpts, sdkmetric.WithProducer(p))

pkg/beholder/config.go

@@ -163,6 +163,13 @@ func DefaultConfig() Config {
 	}
 }
 
+func metricReaderInterval(cfg Config) time.Duration {
+	if cfg.MetricReaderInterval > 0 {
+		return cfg.MetricReaderInterval
+	}
+	return DefaultConfig().MetricReaderInterval
+}
+
 func TestDefaultConfig() Config {
 	config := DefaultConfig()
 	// Should be only disabled for testing

pkg/beholder/config_defaults_test.go

@@ -0,0 +1,15 @@
+package beholder
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMetricReaderInterval_zeroUsesDefault(t *testing.T) {
+	t.Parallel()
+
+	assert.Equal(t, time.Second, metricReaderInterval(Config{}))
+	assert.Equal(t, 5*time.Second, metricReaderInterval(Config{MetricReaderInterval: 5 * time.Second}))
+}

pkg/beholder/httpclient.go

@@ -289,7 +289,7 @@ func newHTTPMeterProvider(config Config, resource *sdkresource.Resource, tlsConf
 		sdkmetric.WithReader(
 			sdkmetric.NewPeriodicReader(
 				exporter,
-				sdkmetric.WithInterval(config.MetricReaderInterval), // Default is 10s
+				sdkmetric.WithInterval(metricReaderInterval(config)), // Zero uses Beholder default (1s)
 			)),
 		sdkmetric.WithResource(resource),
 		sdkmetric.WithView(config.MetricViews...),