Prometheus: Update FrameType and make __name__ the field name (#62694)

These changes would make the response more in line with the dataplane contract, changes are under the feature toggle prometheusDataplane

pkg/services/featuremgmt/registry.go

@@ -454,5 +454,11 @@ var (
 			State:       FeatureStateBeta,
 			Owner:       grafanaObservabilityLogsSquad,
 		},
+		{
+			Name:        "prometheusDataplane",
+			Description: "Changes responses to from Prometheus to be compliant with the dataplane specification. In particular it sets the numeric Field.Name from 'Value' to the value of the `__name__` label when present.",
+			State:       FeatureStateAlpha,
+			Owner:       grafanaObservabilityMetricsSquad,
+		},
 	}
 )

pkg/services/featuremgmt/toggles_gen.csv

@@ -67,3 +67,4 @@ timeSeriesTable,alpha,@grafana/app-o11y,false,false,false,true
 influxdbBackendMigration,alpha,@grafana/observability-metrics,false,false,false,true
 clientTokenRotation,alpha,@grafana/grafana-authnz-team,false,false,false,false
 disableElasticsearchBackendExploreQuery,beta,@grafana/observability-logs,false,false,false,false
+prometheusDataplane,alpha,@grafana/observability-metrics,false,false,false,false

pkg/services/featuremgmt/toggles_gen.go

@@ -278,4 +278,8 @@ const (
 	// FlagDisableElasticsearchBackendExploreQuery
 	// Disable executing of Elasticsearch Explore queries trough backend
 	FlagDisableElasticsearchBackendExploreQuery = "disableElasticsearchBackendExploreQuery"
+
+	// FlagPrometheusDataplane
+	// Changes responses to from Prometheus to be compliant with the dataplane specification. In particular it sets the numeric Field.Name from 'Value' to the value of the `__name__` label when present.
+	FlagPrometheusDataplane = "prometheusDataplane"
 )

pkg/tsdb/prometheus/querydata/request.go

@@ -43,6 +43,7 @@ type QueryData struct {
 	URL                string
 	TimeInterval       string
 	enableWideSeries   bool
+	enableDataplane    bool
 	exemplarSampler    func() exemplar.Sampler
 }
 
@@ -82,6 +83,7 @@ func New(
 		ID:                 settings.ID,
 		URL:                settings.URL,
 		enableWideSeries:   features.IsEnabled(featuremgmt.FlagPrometheusWideSeries),
+		enableDataplane:    features.IsEnabled(featuremgmt.FlagPrometheusDataplane),
 		exemplarSampler:    exemplarSampler,
 	}, nil
 }

pkg/tsdb/prometheus/querydata/response.go

@@ -28,6 +28,7 @@ func (s *QueryData) parseResponse(ctx context.Context, q *models.Query, res *htt
 	r := converter.ReadPrometheusStyleResult(iter, converter.Options{
 		MatrixWideSeries: s.enableWideSeries,
 		VectorWideSeries: s.enableWideSeries,
+		Dataplane:        s.enableDataplane,
 	})
 
 	// Add frame to attach metadata

pkg/util/converter/prom.go

@@ -21,6 +21,7 @@ func logf(format string, a ...interface{}) {
 type Options struct {
 	MatrixWideSeries bool
 	VectorWideSeries bool
+	Dataplane        bool
 }
 
 // ReadPrometheusStyleResult will read results from a prometheus or loki server and return data frames
@@ -115,15 +116,15 @@ func readPrometheusData(iter *jsoniter.Iterator, opt Options) backend.DataRespon
 			switch resultType {
 			case "matrix":
 				if opt.MatrixWideSeries {
-					rsp = readMatrixOrVectorWide(iter, resultType)
+					rsp = readMatrixOrVectorWide(iter, resultType, opt)
 				} else {
-					rsp = readMatrixOrVectorMulti(iter, resultType)
+					rsp = readMatrixOrVectorMulti(iter, resultType, opt)
 				}
 			case "vector":
 				if opt.VectorWideSeries {
-					rsp = readMatrixOrVectorWide(iter, resultType)
+					rsp = readMatrixOrVectorWide(iter, resultType, opt)
 				} else {
-					rsp = readMatrixOrVectorMulti(iter, resultType)
+					rsp = readMatrixOrVectorMulti(iter, resultType, opt)
 				}
 			case "streams":
 				rsp = readStream(iter)
@@ -355,7 +356,7 @@ func readScalar(iter *jsoniter.Iterator) backend.DataResponse {
 
 	frame := data.NewFrame("", timeField, valueField)
 	frame.Meta = &data.FrameMeta{
-		Type:   data.FrameTypeTimeSeriesMulti,
+		Type:   data.FrameTypeNumericMulti,
 		Custom: resultTypeToCustomMeta("scalar"),
 	}
 
@@ -364,16 +365,25 @@ func readScalar(iter *jsoniter.Iterator) backend.DataResponse {
 	}
 }
 
-func readMatrixOrVectorWide(iter *jsoniter.Iterator, resultType string) backend.DataResponse {
+func readMatrixOrVectorWide(iter *jsoniter.Iterator, resultType string, opt Options) backend.DataResponse {
 	rowIdx := 0
 	timeMap := map[int64]int{}
 	timeField := data.NewFieldFromFieldType(data.FieldTypeTime, 0)
 	timeField.Name = data.TimeSeriesTimeFieldName
 	frame := data.NewFrame("", timeField)
-	frame.Meta = &data.FrameMeta{
+
+	frame.Meta = &data.FrameMeta{ // Overwritten if histogram
 		Type:   data.FrameTypeTimeSeriesWide,
 		Custom: resultTypeToCustomMeta(resultType),
 	}
+
+	if opt.Dataplane && resultType == "vector" {
+		frame.Meta.Type = data.FrameTypeNumericWide
+	}
+	if opt.Dataplane {
+		frame.Meta.TypeVersion = data.FrameTypeVersion{0, 1}
+	}
+
 	rsp := backend.DataResponse{
 		Frames: []*data.Frame{},
 	}
@@ -390,6 +400,11 @@ func readMatrixOrVectorWide(iter *jsoniter.Iterator, resultType string) backend.
 			switch l1Field {
 			case "metric":
 				iter.ReadVal(&valueField.Labels)
+				if opt.Dataplane {
+					if n, ok := valueField.Labels["__name__"]; ok {
+						valueField.Name = n
+					}
+				}
 
 			case "value":
 				timeMap, rowIdx = addValuePairToFrame(frame, timeMap, rowIdx, iter)
@@ -472,7 +487,7 @@ func addValuePairToFrame(frame *data.Frame, timeMap map[int64]int, rowIdx int, i
 	return timeMap, rowIdx
 }
 
-func readMatrixOrVectorMulti(iter *jsoniter.Iterator, resultType string) backend.DataResponse {
+func readMatrixOrVectorMulti(iter *jsoniter.Iterator, resultType string, opt Options) backend.DataResponse {
 	rsp := backend.DataResponse{}
 
 	for iter.ReadArray() {
@@ -488,6 +503,11 @@ func readMatrixOrVectorMulti(iter *jsoniter.Iterator, resultType string) backend
 			switch l1Field {
 			case "metric":
 				iter.ReadVal(&valueField.Labels)
+				if opt.Dataplane {
+					if n, ok := valueField.Labels["__name__"]; ok {
+						valueField.Name = n
+					}
+				}
 
 			case "value":
 				t, v, err := readTimeValuePair(iter)
@@ -548,6 +568,12 @@ func readMatrixOrVectorMulti(iter *jsoniter.Iterator, resultType string) backend
 				Type:   data.FrameTypeTimeSeriesMulti,
 				Custom: resultTypeToCustomMeta(resultType),
 			}
+			if opt.Dataplane && resultType == "vector" {
+				frame.Meta.Type = data.FrameTypeNumericMulti
+			}
+			if opt.Dataplane {
+				frame.Meta.TypeVersion = data.FrameTypeVersion{0, 1}
+			}
 			rsp.Frames = append(rsp.Frames, frame)
 		}
 	}