fix(prom-dup-labels): added fingerprint in prom labels (#8563)

* fix(prom-dup-labels): added fingerprint in prom labels

* fix(prom-dup-labels): removed fingerprint labels from result series

* fix(prom-dup-labels): removed fingerprint labels from result series

* fix(prom-dup-labels): removed fingerprint labels from result series

* fix(prom-dup-labels): removed fingerprint labels from result series

* fix(prom-dup-labels): added test cases

* Update pkg/prometheus/clickhouseprometheus/client_query_test.go

Co-authored-by: ellipsis-dev[bot] <65095814+ellipsis-dev[bot]@users.noreply.github.com>

* fix(prom-dup-labels): added test cases

---------

Co-authored-by: ellipsis-dev[bot] <65095814+ellipsis-dev[bot]@users.noreply.github.com>

pkg/prometheus/clickhouseprometheus/client.go

@@ -151,7 +151,7 @@ func (client *client) getFingerprintsFromClickhouseQuery(ctx context.Context, qu
 			return nil, err
 		}
 
-		labels, _, err := unmarshalLabels(labelString)
+		labels, _, err := unmarshalLabels(labelString, fingerprint)
 		if err != nil {
 			return nil, err
 		}

pkg/prometheus/clickhouseprometheus/client_query_test.go

@@ -4,6 +4,8 @@ import (
 	"context"
 	"github.com/SigNoz/signoz/pkg/telemetrystore/telemetrystoretest"
 	cmock "github.com/srikanthccv/ClickHouse-go-mock"
+	"github.com/stretchr/testify/require"
+	"sort"
 	"testing"
 
 	"github.com/DATA-DOG/go-sqlmock"
@@ -111,3 +113,97 @@ func TestClient_QuerySamples(t *testing.T) {
 		})
 	}
 }
+
+func TestClient_getFingerprintsFromClickhouseQuery(t *testing.T) {
+	cols := []cmock.ColumnType{
+		{Name: "fingerprint", Type: "UInt64"},
+		{Name: "labels", Type: "String"},
+	}
+
+	sortLabels := func(ls []prompb.Label) {
+		sort.Slice(ls, func(i, j int) bool {
+			if ls[i].Name == ls[j].Name {
+				return ls[i].Value < ls[j].Value
+			}
+			return ls[i].Name < ls[j].Name
+		})
+	}
+
+	tests := []struct {
+		name       string
+		start, end int64
+		metricName string
+		subQuery   string
+		args       []any
+		setupMock  func(m cmock.ClickConnMockCommon, args ...any)
+		want       map[uint64][]prompb.Label
+		wantErr    bool
+	}{
+		{
+			name:       "happy-path - two fingerprints",
+			start:      1000,
+			end:        2000,
+			metricName: "cpu_usage",
+			subQuery:   `SELECT fingerprint,labels`,
+			// args slice is empty here, but test‑case still owns it
+			args: []any{},
+
+			setupMock: func(m cmock.ClickConnMockCommon, args ...any) {
+				rows := [][]any{
+					{uint64(123), `{"t1":"s1","t2":"s2"}`},
+					{uint64(234), `{"t1":"s1","t2":"s2"}`},
+				}
+				m.ExpectQuery(`SELECT fingerprint,labels`).WithArgs(args...).WillReturnRows(
+					cmock.NewRows(cols, rows),
+				)
+			},
+
+			want: map[uint64][]prompb.Label{
+				123: {
+					{Name: "fingerprint", Value: "123"},
+					{Name: "t1", Value: "s1"},
+					{Name: "t2", Value: "s2"},
+				},
+				234: {
+					{Name: "fingerprint", Value: "234"},
+					{Name: "t1", Value: "s1"},
+					{Name: "t2", Value: "s2"},
+				},
+			},
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			ctx := context.Background()
+			store := telemetrystoretest.New(
+				telemetrystore.Config{Provider: "clickhouse"},
+				sqlmock.QueryMatcherRegexp,
+			)
+
+			if tc.setupMock != nil {
+				tc.setupMock(store.Mock(), tc.args...)
+			}
+
+			c := client{telemetryStore: store}
+
+			got, err := c.getFingerprintsFromClickhouseQuery(ctx, tc.subQuery, tc.args)
+			if tc.wantErr {
+				require.Error(t, err)
+				require.Nil(t, got)
+				return
+			}
+			require.NoError(t, err)
+			require.Equal(t, len(tc.want), len(got), "fingerprint map length mismatch")
+			for fp, expLabels := range tc.want {
+				gotLabels, ok := got[fp]
+				require.Truef(t, ok, "missing fingerprint %d", fp)
+
+				sortLabels(expLabels)
+				sortLabels(gotLabels)
+
+				assert.Equalf(t, expLabels, gotLabels, "labels mismatch for fingerprint %d", fp)
+			}
+		})
+	}
+}

pkg/prometheus/clickhouseprometheus/json.go

@@ -2,12 +2,14 @@ package clickhouseprometheus
 
 import (
 	"encoding/json"
+	"strconv"
 
+	"github.com/SigNoz/signoz/pkg/prometheus"
 	"github.com/prometheus/prometheus/prompb"
 )
 
 // Unmarshals JSON into Prometheus labels. It does not preserve order.
-func unmarshalLabels(s string) ([]prompb.Label, string, error) {
+func unmarshalLabels(s string, fingerprint uint64) ([]prompb.Label, string, error) {
 	var metricName string
 	m := make(map[string]string)
 	if err := json.Unmarshal([]byte(s), &m); err != nil {
@@ -24,5 +26,9 @@ func unmarshalLabels(s string) ([]prompb.Label, string, error) {
 			Value: v,
 		})
 	}
+	res = append(res, prompb.Label{
+		Name:  prometheus.FingerprintAsPromLabelName,
+		Value: strconv.FormatUint(fingerprint, 10),
+	})
 	return res, metricName, nil
 }

pkg/prometheus/constants.go

@@ -0,0 +1,3 @@
+package prometheus
+
+const FingerprintAsPromLabelName = "fingerprint"

pkg/prometheus/prometheustest/utils_test.go

@@ -0,0 +1,106 @@
+package prometheustest
+
+import (
+	"github.com/SigNoz/signoz/pkg/prometheus"
+	"github.com/prometheus/prometheus/model/labels"
+	"github.com/prometheus/prometheus/promql"
+	"testing"
+)
+
+func TestRemoveExtraLabels(t *testing.T) {
+
+	tests := []struct {
+		name    string
+		res     *promql.Result
+		remove  []string
+		wantErr bool
+		verify  func(t *testing.T, result *promql.Result, removed []string)
+	}{
+		{
+			name: "vector – label removed",
+			res: &promql.Result{
+				Value: promql.Vector{
+					promql.Sample{
+						Metric: labels.FromStrings(
+							"__name__", "http_requests_total",
+							"job", "demo",
+							"drop_me", "dropped",
+						),
+					},
+				},
+			},
+			remove: []string{"drop_me"},
+			verify: func(t *testing.T, result *promql.Result, removed []string) {
+				k := result.Value.(promql.Vector)
+				for _, str := range removed {
+					get := k[0].Metric.Get(str)
+					if get != "" {
+						t.Fatalf("label not removed")
+					}
+				}
+			},
+		},
+		{
+			name: "scalar – nothing to strip",
+			res: &promql.Result{
+				Value: promql.Scalar{V: 99, T: 1},
+			},
+			remove: []string{"irrelevant"},
+			verify: func(t *testing.T, result *promql.Result, removed []string) {
+				sc := result.Value.(promql.Scalar)
+				if sc.V != 99 || sc.T != 1 {
+					t.Fatalf("scalar unexpectedly modified: got %+v", sc)
+				}
+			},
+		},
+		{
+			name: "matrix – label removed",
+			res: &promql.Result{
+				Value: promql.Matrix{
+					promql.Series{
+						Metric: labels.FromStrings(
+							"__name__", "http_requests_total",
+							"pod", "p0",
+							"drop_me", "dropped",
+						),
+						Floats: []promql.FPoint{{T: 0, F: 1}, {T: 1, F: 2}},
+					},
+					promql.Series{
+						Metric: labels.FromStrings(
+							"__name__", "http_requests_total",
+							"pod", "p0",
+							"drop_me", "dropped",
+						),
+						Floats: []promql.FPoint{{T: 0, F: 1}, {T: 1, F: 2}},
+					},
+				},
+			},
+			remove: []string{"drop_me"},
+			verify: func(t *testing.T, result *promql.Result, removed []string) {
+				mat := result.Value.(promql.Matrix)
+				for _, str := range removed {
+					for _, k := range mat {
+						if k.Metric.Get(str) != "" {
+							t.Fatalf("label not removed")
+						}
+					}
+				}
+			},
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			err := prometheus.RemoveExtraLabels(tc.res, tc.remove...)
+			if tc.wantErr && err == nil {
+				t.Fatalf("expected error, got nil")
+			}
+			if !tc.wantErr && err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+			if tc.verify != nil {
+				tc.verify(t, tc.res, tc.remove)
+			}
+		})
+	}
+}

pkg/prometheus/utils.go

@@ -0,0 +1,49 @@
+package prometheus
+
+import (
+	"fmt"
+	"github.com/prometheus/prometheus/promql"
+)
+
+func RemoveExtraLabels(res *promql.Result, labelsToRemove ...string) error {
+	if len(labelsToRemove) == 0 || res == nil {
+		return nil
+	}
+
+	toRemove := make(map[string]struct{}, len(labelsToRemove))
+	for _, l := range labelsToRemove {
+		toRemove[l] = struct{}{}
+	}
+
+	switch res.Value.(type) {
+	case promql.Vector:
+		value := res.Value.(promql.Vector)
+		for i := range value {
+			series := &(value)[i]
+			dst := series.Metric[:0]
+			for _, lbl := range series.Metric {
+				if _, drop := toRemove[lbl.Name]; !drop {
+					dst = append(dst, lbl)
+				}
+			}
+			series.Metric = dst
+		}
+	case promql.Matrix:
+		value := res.Value.(promql.Matrix)
+		for i := range value {
+			series := &(value)[i]
+			dst := series.Metric[:0]
+			for _, lbl := range series.Metric {
+				if _, drop := toRemove[lbl.Name]; !drop {
+					dst = append(dst, lbl)
+				}
+			}
+			series.Metric = dst
+		}
+	case promql.Scalar:
+		return nil
+	default:
+		return fmt.Errorf("rule result is not a vector or scalar or matrix")
+	}
+	return nil
+}

pkg/query-service/app/clickhouseReader/reader.go

@@ -239,6 +239,10 @@ func (r *ClickHouseReader) GetInstantQueryMetricsResult(ctx context.Context, que
 	}
 
 	qry.Close()
+	err = prometheus.RemoveExtraLabels(res, prometheus.FingerprintAsPromLabelName)
+	if err != nil {
+		return nil, nil, &model.ApiError{Typ: model.ErrorInternal, Err: err}
+	}
 	return res, &qs, nil
 
 }
@@ -259,6 +263,10 @@ func (r *ClickHouseReader) GetQueryRangeResult(ctx context.Context, query *model
 	}
 
 	qry.Close()
+	err = prometheus.RemoveExtraLabels(res, prometheus.FingerprintAsPromLabelName)
+	if err != nil {
+		return nil, nil, &model.ApiError{Typ: model.ErrorInternal, Err: err}
+	}
 	return res, &qs, nil
 }
 

pkg/query-service/rules/prom_rule.go

@@ -321,6 +321,11 @@ func (r *PromRule) RunAlertQuery(ctx context.Context, qs string, start, end time
 		return nil, res.Err
 	}
 
+	err = prometheus.RemoveExtraLabels(res, prometheus.FingerprintAsPromLabelName)
+	if err != nil {
+		return nil, err
+	}
+
 	switch typ := res.Value.(type) {
 	case promql.Vector:
 		series := make([]promql.Series, 0, len(typ))