prometheusremotewrite: Move TimeSeries method to timeseries.go

To facilitate generating OTel translation code for other Prometheus
compatible backends, modify the prometheusremotewrite sources slightly
so that the PrometheusConverter.TimeSeries method is in a file called
timeseries.go. The rationale is to allow other backends to define their
own implementation of this method.

Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>

storage/remote/otlptranslator/prometheusremotewrite/metrics_to_prw.go

@@ -38,7 +38,7 @@ type Settings struct {
 	SendMetadata        bool
 }
 
-// PrometheusConverter converts from OTel write format to Prometheus write format.
+// PrometheusConverter converts from OTel write format to Prometheus remote write format.
 type PrometheusConverter struct {
 	unique    map[uint64]*prompb.TimeSeries
 	conflicts map[uint64][]*prompb.TimeSeries
@@ -130,25 +130,6 @@ func (c *PrometheusConverter) FromMetrics(md pmetric.Metrics, settings Settings)
 	return
 }
 
-// TimeSeries returns a slice of the prompb.TimeSeries that were converted from OTel format.
-func (c *PrometheusConverter) TimeSeries() []prompb.TimeSeries {
-	conflicts := 0
-	for _, ts := range c.conflicts {
-		conflicts += len(ts)
-	}
-	allTS := make([]prompb.TimeSeries, 0, len(c.unique)+conflicts)
-	for _, ts := range c.unique {
-		allTS = append(allTS, *ts)
-	}
-	for _, cTS := range c.conflicts {
-		for _, ts := range cTS {
-			allTS = append(allTS, *ts)
-		}
-	}
-
-	return allTS
-}
-
 func isSameMetric(ts *prompb.TimeSeries, lbls []prompb.Label) bool {
 	if len(ts.Labels) != len(lbls) {
 		return false

storage/remote/otlptranslator/prometheusremotewrite/metrics_to_prw_test.go

@@ -64,7 +64,7 @@ func BenchmarkPrometheusConverter_FromMetrics(b *testing.B) {
 	}
 }
 
-func createExportRequest(resourceAttributeCount int, histogramCount int, nonHistogramCount int, labelsPerMetric int, exemplarsPerSeries int) pmetricotlp.ExportRequest {
+func createExportRequest(resourceAttributeCount, histogramCount, nonHistogramCount, labelsPerMetric, exemplarsPerSeries int) pmetricotlp.ExportRequest {
 	request := pmetricotlp.NewExportRequest()
 
 	rm := request.Metrics().ResourceMetrics().AppendEmpty()

storage/remote/otlptranslator/prometheusremotewrite/timeseries.go

@@ -0,0 +1,41 @@
+// Copyright 2024 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// Provenance-includes-location:
+// https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/95e8f8fdc2a9dc87230406c9a3cf02be4fd68bea/pkg/translator/prometheusremotewrite/metrics_to_prw.go
+// Provenance-includes-license: Apache-2.0
+// Provenance-includes-copyright: Copyright The OpenTelemetry Authors.
+
+package prometheusremotewrite
+
+import (
+	"github.com/prometheus/prometheus/prompb"
+)
+
+// TimeSeries returns a slice of the prompb.TimeSeries that were converted from OTel format.
+func (c *PrometheusConverter) TimeSeries() []prompb.TimeSeries {
+	conflicts := 0
+	for _, ts := range c.conflicts {
+		conflicts += len(ts)
+	}
+	allTS := make([]prompb.TimeSeries, 0, len(c.unique)+conflicts)
+	for _, ts := range c.unique {
+		allTS = append(allTS, *ts)
+	}
+	for _, cTS := range c.conflicts {
+		for _, ts := range cTS {
+			allTS = append(allTS, *ts)
+		}
+	}
+
+	return allTS
+}