Add idea for an output that aggregates before adding to metric buffer

internal/models/running_output.go

@@ -113,6 +113,11 @@ func (ro *RunningOutput) AddMetric(m telegraf.Metric) {
 		m, _ = metric.New(name, tags, fields, t)
 	}
 
+	if output, ok := ro.Output.(telegraf.AggregatingOutput); ok {
+		output.Add(m)
+		return
+	}
+
 	ro.metrics.Add(m)
 	if ro.metrics.Len() == ro.MetricBatchSize {
 		batch := ro.metrics.Batch(ro.MetricBatchSize)
@@ -125,6 +130,12 @@ func (ro *RunningOutput) AddMetric(m telegraf.Metric) {
 
 // Write writes all cached points to this output.
 func (ro *RunningOutput) Write() error {
+	if output, ok := ro.Output.(telegraf.AggregatingOutput); ok {
+		metrics := output.Push()
+		ro.metrics.Add(metrics...)
+		output.Reset()
+	}
+
 	nFails, nMetrics := ro.failMetrics.Len(), ro.metrics.Len()
 	ro.BufferSize.Set(int64(nFails + nMetrics))
 	log.Printf("D! Output [%s] buffer fullness: %d / %d metrics. ",

output.go

@@ -13,6 +13,12 @@ type Output interface {
 	Write(metrics []Metric) error
 }
 
+type AggregatingOutput interface {
+	Add(in Metric)
+	Push() []Metric
+	Reset()
+}
+
 type ServiceOutput interface {
 	// Connect to the Output
 	Connect() error