Jm prom translation rw2 add support for summaries (#40750)

<!--Ex. Fixing a bug - Describe the bug and how this fixes the issue.
Ex. Adding a feature - Explain what this achieves.-->
#### Description

Adds support for adding summaries in the RW2 translation path.

<!-- Issue number (e.g. #1234) or full URL to issue, if applicable. -->
#### Link to tracking issue
Fixes

Partially implements
#33661
(when merging PR please don't close the tracing issue)

<!--Describe what testing was performed and which tests were added.-->
#### Testing

* [x] Added unit test
* [ ] e2e ran with prometheus

Review please @ArthurSens @dashpole @krajorama @ywwg

---------

Co-authored-by: David Ashpole <[email protected]>

Author: jmichalek132

.chloggen/jm-prom-translation-rw2-add-support-for-summaries.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: pkg/translator/prometheusremotewrite
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "`FromMetricsV2` now supports translating summaries."
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [33661]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext: The translation layer for Prometheus remote write 2 now supports summaries but is not fully implemented and ready for use.
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

pkg/translator/prometheusremotewrite/helper_v2.go

@@ -4,9 +4,15 @@
 package prometheusremotewrite // import "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/translator/prometheusremotewrite"
 
 import (
+	"math"
+	"strconv"
+
 	"github.com/prometheus/common/model"
+	"github.com/prometheus/prometheus/model/value"
+	"github.com/prometheus/prometheus/prompb"
 	writev2 "github.com/prometheus/prometheus/prompb/io/prometheus/write/v2"
 	"go.opentelemetry.io/collector/pdata/pcommon"
+	"go.opentelemetry.io/collector/pdata/pmetric"
 	conventions "go.opentelemetry.io/otel/semconv/v1.25.0"
 
 	prometheustranslator "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/translator/prometheus"
@@ -66,3 +72,43 @@ func (c *prometheusConverterV2) addResourceTargetInfoV2(resource pcommon.Resourc
 		Help: "Target metadata",
 	})
 }
+
+// addSampleWithLabels is a helper function to create and add a sample with labels
+func (c *prometheusConverterV2) addSampleWithLabels(sampleValue float64, timestamp int64, noRecordedValue bool,
+	baseName string, baseLabels []prompb.Label, labelName, labelValue string, metadata metadata,
+) {
+	sample := &writev2.Sample{
+		Value:     sampleValue,
+		Timestamp: timestamp,
+	}
+	if noRecordedValue {
+		sample.Value = math.Float64frombits(value.StaleNaN)
+	}
+	if labelName != "" && labelValue != "" {
+		c.addSample(sample, createLabels(baseName, baseLabels, labelName, labelValue), metadata)
+	} else {
+		c.addSample(sample, createLabels(baseName, baseLabels), metadata)
+	}
+}
+
+func (c *prometheusConverterV2) addSummaryDataPoints(dataPoints pmetric.SummaryDataPointSlice, resource pcommon.Resource,
+	settings Settings, baseName string, metadata metadata,
+) {
+	for x := 0; x < dataPoints.Len(); x++ {
+		pt := dataPoints.At(x)
+		timestamp := convertTimeStamp(pt.Timestamp())
+		baseLabels := createAttributes(resource, pt.Attributes(), settings.ExternalLabels, nil, false)
+		noRecordedValue := pt.Flags().NoRecordedValue()
+
+		// Add sum and count samples
+		c.addSampleWithLabels(pt.Sum(), timestamp, noRecordedValue, baseName+sumStr, baseLabels, "", "", metadata)
+		c.addSampleWithLabels(float64(pt.Count()), timestamp, noRecordedValue, baseName+countStr, baseLabels, "", "", metadata)
+
+		// Process quantiles
+		for i := 0; i < pt.QuantileValues().Len(); i++ {
+			qt := pt.QuantileValues().At(i)
+			percentileStr := strconv.FormatFloat(qt.Quantile(), 'f', -1, 64)
+			c.addSampleWithLabels(qt.Value(), timestamp, noRecordedValue, baseName, baseLabels, quantileStr, percentileStr, metadata)
+		}
+	}
+}

pkg/translator/prometheusremotewrite/helper_v2_test.go

@@ -5,16 +5,19 @@ package prometheusremotewrite
 
 import (
 	"testing"
+	"time"
 
 	"github.com/prometheus/common/model"
 	"github.com/prometheus/prometheus/prompb"
 	writev2 "github.com/prometheus/prometheus/prompb/io/prometheus/write/v2"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"go.opentelemetry.io/collector/pdata/pcommon"
+	"go.opentelemetry.io/collector/pdata/pmetric"
 	conventions "go.opentelemetry.io/otel/semconv/v1.25.0"
 
 	"github.com/open-telemetry/opentelemetry-collector-contrib/internal/coreinternal/testdata"
+	prometheustranslator "github.com/open-telemetry/opentelemetry-collector-contrib/pkg/translator/prometheus"
 )
 
 func TestAddResourceTargetInfoV2(t *testing.T) {
@@ -153,3 +156,124 @@ func TestAddResourceTargetInfoV2(t *testing.T) {
 		})
 	}
 }
+
+func TestPrometheusConverterV2_AddSummaryDataPoints(t *testing.T) {
+	ts := pcommon.Timestamp(time.Now().UnixNano())
+	tests := []struct {
+		name   string
+		metric func() pmetric.Metric
+		want   func() map[uint64]*writev2.TimeSeries
+	}{
+		{
+			name: "summary with start time",
+			metric: func() pmetric.Metric {
+				metric := pmetric.NewMetric()
+				metric.SetName("test_summary")
+				metric.SetEmptySummary()
+
+				dp := metric.Summary().DataPoints().AppendEmpty()
+				dp.SetTimestamp(ts)
+				dp.SetStartTimestamp(ts)
+
+				return metric
+			},
+			want: func() map[uint64]*writev2.TimeSeries {
+				labels := []prompb.Label{
+					{Name: model.MetricNameLabel, Value: "test_summary" + countStr},
+				}
+				sumLabels := []prompb.Label{
+					{Name: model.MetricNameLabel, Value: "test_summary" + sumStr},
+				}
+				return map[uint64]*writev2.TimeSeries{
+					timeSeriesSignature(labels): {
+						LabelsRefs: []uint32{1, 3},
+						Samples: []writev2.Sample{
+							{Value: 0, Timestamp: convertTimeStamp(ts)},
+						},
+						Metadata: writev2.Metadata{
+							Type:    writev2.Metadata_METRIC_TYPE_SUMMARY,
+							HelpRef: 0,
+						},
+					},
+					timeSeriesSignature(sumLabels): {
+						LabelsRefs: []uint32{1, 2},
+						Samples: []writev2.Sample{
+							{Value: 0, Timestamp: convertTimeStamp(ts)},
+						},
+						Metadata: writev2.Metadata{
+							Type:    writev2.Metadata_METRIC_TYPE_SUMMARY,
+							HelpRef: 0,
+						},
+					},
+				}
+			},
+		},
+		{
+			name: "summary without start time",
+			metric: func() pmetric.Metric {
+				metric := pmetric.NewMetric()
+				metric.SetName("test_summary")
+				metric.SetEmptySummary()
+
+				dp := metric.Summary().DataPoints().AppendEmpty()
+				dp.SetTimestamp(ts)
+
+				return metric
+			},
+			want: func() map[uint64]*writev2.TimeSeries {
+				labels := []prompb.Label{
+					{Name: model.MetricNameLabel, Value: "test_summary" + countStr},
+				}
+				sumLabels := []prompb.Label{
+					{Name: model.MetricNameLabel, Value: "test_summary" + sumStr},
+				}
+				return map[uint64]*writev2.TimeSeries{
+					timeSeriesSignature(labels): {
+						LabelsRefs: []uint32{1, 3},
+						Samples: []writev2.Sample{
+							{Value: 0, Timestamp: convertTimeStamp(ts)},
+						},
+						Metadata: writev2.Metadata{
+							Type:    writev2.Metadata_METRIC_TYPE_SUMMARY,
+							HelpRef: 0,
+						},
+					},
+					timeSeriesSignature(sumLabels): {
+						LabelsRefs: []uint32{1, 2},
+						Samples: []writev2.Sample{
+							{Value: 0, Timestamp: convertTimeStamp(ts)},
+						},
+						Metadata: writev2.Metadata{
+							Type:    writev2.Metadata_METRIC_TYPE_SUMMARY,
+							HelpRef: 0,
+						},
+					},
+				}
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			metric := tt.metric()
+			converter := newPrometheusConverterV2()
+
+			m := metadata{
+				Type: otelMetricTypeToPromMetricTypeV2(metric),
+				Help: metric.Description(),
+				Unit: prometheustranslator.BuildCompliantPrometheusUnit(metric.Unit()),
+			}
+
+			converter.addSummaryDataPoints(
+				metric.Summary().DataPoints(),
+				pcommon.NewResource(),
+				Settings{},
+				metric.Name(),
+				m,
+			)
+
+			assert.Equal(t, tt.want(), converter.unique)
+			// TODO check when conflicts handling is implemented
+			// assert.Empty(t, converter.conflicts)
+		})
+	}
+}

pkg/translator/prometheusremotewrite/metrics_to_prw_v2.go

@@ -105,7 +105,11 @@ func (c *prometheusConverterV2) fromMetrics(md pmetric.Metrics, settings Setting
 				case pmetric.MetricTypeExponentialHistogram:
 					// TODO implement
 				case pmetric.MetricTypeSummary:
-					// TODO implement
+					dataPoints := metric.Summary().DataPoints()
+					if dataPoints.Len() == 0 {
+						break
+					}
+					c.addSummaryDataPoints(dataPoints, resource, settings, promName, m)
 				default:
 					errs = multierr.Append(errs, errors.New("unsupported metric type"))
 				}