Added check for empty reports

src/extensions/advanced-metrics/pkg/publisher/publisher_test.go

@@ -20,6 +20,13 @@ func TestPublisher(t *testing.T) {
 		expectedMetrics   []*MetricSet
 		dimensionsLookups map[int]map[int]string
 	}{
+		{
+			name: "no metric with no dimension",
+			schema: schema.NewSchema([]*schema.Field{}...),
+			samples: map[string]*sample.Sample{},
+			dimensionsLookups: map[int]map[int]string{},
+			expectedMetrics: []*MetricSet{},
+		},
 		{
 			name: "single metric with single dimension",
 			schema: schema.NewSchema([]*schema.Field{

src/plugins/advanced_metrics.go

@@ -226,7 +226,10 @@ func (m *AdvancedMetrics) run() {
 				return
 			}
 			now := types.TimestampNow()
-			m.pipeline.Process(core.NewMessage(core.CommMetrics, []core.Payload{toMetricReport(mr, now, commonDimensions)}))
+			report := toMetricReport(mr, now, commonDimensions)
+			if len(report.Data) != 0 {
+				m.pipeline.Process(core.NewMessage(core.CommMetrics, []core.Payload{report}))
+			}
 		case <-m.pipeline.Context().Done():
 			return
 		}

test/component/advanced_metrics_component_test.go

@@ -53,7 +53,7 @@ var (
 )
 
 func init() {
-	logrus.SetLevel(logrus.DebugLevel)
+	logrus.SetLevel(logrus.TraceLevel)
 }
 
 // TestAdvancedMetricsSimple this is simple test which presents basic logic of advanced_metrics module