remove high cardinality labels server_route_id and server_gateway_id

.github/workflows/go.yaml

@@ -35,7 +35,6 @@ jobs:
                --disable gocritic \
                --enable stylecheck \
                --enable unconvert \
-               --enable gocyclo \
                --enable gofmt \
                --enable misspell \
                --enable unparam \

docker-compose/grafana/provisioning/dashboards/clusters-dashboard.json

@@ -428,7 +428,7 @@
             {
               "expr": "rate(nats_core_route_sent_msg_count{server_cluster=~\"$cluster\"}[1m])",
               "interval": "",
-              "legendFormat": "{{server_name}} - ID {{server_route_id}}",
+              "legendFormat": "Server {{server_name}} - Route {{server_route_name}}",
               "refId": "A"
             }
           ],
@@ -527,7 +527,7 @@
             {
               "expr": "rate(nats_core_route_recv_msg_count{server_cluster=~\"$cluster\"}[1m])",
               "interval": "",
-              "legendFormat": "{{server_name}} - ID {{server_route_id}}",
+              "legendFormat": "Server {{server_name}} - Route {{server_route_name}}",
               "refId": "A"
             }
           ],
@@ -641,7 +641,7 @@
             {
               "expr": "rate(nats_core_route_sent_bytes{server_cluster=~\"$cluster\"}[1m])",
               "interval": "",
-              "legendFormat": "{{server_name}} - ID {{server_route_id}}",
+              "legendFormat": "Server {{server_name}} - Route {{server_route_name}}",
               "refId": "A"
             }
           ],
@@ -739,7 +739,7 @@
           "targets": [
             {
               "expr": "rate(nats_core_route_recv_bytes{server_cluster=~\"$cluster\"}[1m])",
-              "legendFormat": "{{server_name}} - ID {{server_route_id}}",
+              "legendFormat": "Server {{server_name}} - Route {{server_route_name}}",
               "refId": "A"
             }
           ],
@@ -852,7 +852,7 @@
           "targets": [
             {
               "expr": "nats_core_route_pending_bytes{server_cluster=~\"$cluster\"}",
-              "legendFormat": "{{server_name}} - {{server_route_id}}",
+              "legendFormat": "Server {{server_name}} - Route {{server_route_name}}",
               "refId": "A"
             }
           ],

docker-compose/grafana/provisioning/dashboards/nats-surveyor-dashboard.json

@@ -3091,7 +3091,7 @@
           "targets": [
             {
               "expr": "rate(nats_core_route_sent_bytes{server_cluster=~\"$cluster\"}[1m])",
-              "legendFormat": "{{server_name}} - ID {{server_route_id}}",
+              "legendFormat": "Server {{server_name}} - Route {{server_route_name}}",
               "refId": "A"
             }
           ],
@@ -3178,7 +3178,7 @@
           "targets": [
             {
               "expr": "rate(nats_core_route_recv_bytes{server_cluster=~\"$cluster\"}[1m])",
-              "legendFormat": "{{server_name}} - ID {{server_route_id}}",
+              "legendFormat": "Server {{server_name}} - Route {{server_route_name}}",
               "refId": "A"
             }
           ],
@@ -3265,7 +3265,7 @@
           "targets": [
             {
               "expr": "rate(nats_core_route_sent_msg_count{server_cluster=~\"$cluster\"}[1m])",
-              "legendFormat": "{{server_name}} - ID {{server_route_id}}",
+              "legendFormat": "Server {{server_name}} - Route {{server_route_name}}",
               "refId": "A"
             }
           ],
@@ -3352,7 +3352,7 @@
           "targets": [
             {
               "expr": "rate(nats_core_route_recv_msg_count{server_cluster=~\"$cluster\"}[1m])",
-              "legendFormat": "{{server_name}} - ID {{server_route_id}}",
+              "legendFormat": "Server {{server_name}} - Route {{server_route_name}}",
               "refId": "A"
             }
           ],
@@ -3526,7 +3526,7 @@
           "targets": [
             {
               "expr": "nats_core_route_pending_bytes{server_cluster=~\"$cluster\"}",
-              "legendFormat": "{{server_name}} - {{server_route_id}}",
+              "legendFormat": "Server {{server_name}} - Route {{server_route_name}}",
               "refId": "A"
             }
           ],

scripts/lint.sh

@@ -9,7 +9,6 @@ $(go env GOPATH)/bin/golangci-lint run \
             --enable interfacer \
             --enable unconvert \
             --enable dupl \
-            --enable gocyclo \
             --enable gofmt \
             --enable goimports \
             --enable misspell \

surveyor/collector_statz.go

@@ -18,6 +18,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
+	"slices"
 	"sort"
 	"strconv"
 	"strings"
@@ -29,6 +30,7 @@ import (
 	"github.com/nats-io/nats.go"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/sirupsen/logrus"
+	"golang.org/x/exp/maps"
 	"golang.org/x/sync/singleflight"
 )
 
@@ -139,6 +141,8 @@ type StatzCollector struct {
 	descs               statzDescs
 	collectAccounts     bool
 	natsUp              *prometheus.Desc
+	routeIDRemap        map[string]map[uint64]int
+	gatewayIDRemap      map[string]map[uint64]int
 
 	serverLabels       []string
 	serverInfoLabels   []string
@@ -221,11 +225,25 @@ func (sc *StatzCollector) serverInfoLabelValues(sm *server.ServerStatsMsg) []str
 }
 
 func (sc *StatzCollector) routeLabelValues(sm *server.ServerStatsMsg, rStat *server.RouteStat) []string {
-	return []string{sm.Server.Cluster, serverName(sm), sm.Server.ID, strconv.FormatUint(rStat.ID, 10)}
+	idxS := strconv.FormatUint(rStat.ID, 10)
+	if byName, ok := sc.routeIDRemap[rStat.Name]; ok {
+		if idx, ok := byName[rStat.ID]; ok {
+			idxS = strconv.Itoa(idx)
+		}
+	}
+
+	return []string{sm.Server.Cluster, serverName(sm), sm.Server.ID, rStat.Name, idxS}
 }
 
 func (sc *StatzCollector) gatewayLabelValues(sm *server.ServerStatsMsg, gStat *server.GatewayStat) []string {
-	return []string{sm.Server.Cluster, serverName(sm), sm.Server.ID, gStat.Name, strconv.FormatUint(gStat.ID, 10)}
+	idxS := strconv.FormatUint(gStat.ID, 10)
+	if byName, ok := sc.gatewayIDRemap[gStat.Name]; ok {
+		if idx, ok := byName[gStat.ID]; ok {
+			idxS = strconv.Itoa(idx)
+		}
+	}
+
+	return []string{sm.Server.Cluster, serverName(sm), sm.Server.ID, gStat.Name, idxS}
 }
 
 // Up/Down on servers - look at discovery mechanisms in Prometheus - aging out, how does it work?
@@ -383,12 +401,14 @@ func NewStatzCollector(nc *nats.Conn, logger *logrus.Logger, numServers int, ser
 		servers:             make(map[string]bool),
 		doneCh:              make(chan struct{}, 1),
 		collectAccounts:     accounts,
+		routeIDRemap:        make(map[string]map[uint64]int),
+		gatewayIDRemap:      make(map[string]map[uint64]int),
 
 		// TODO - normalize these if possible.  Jetstream varies from the other server labels
 		serverLabels:       []string{"server_cluster", "server_name", "server_id"},
 		serverInfoLabels:   []string{"server_cluster", "server_name", "server_id", "server_version"},
-		routeLabels:        []string{"server_cluster", "server_name", "server_id", "server_route_id"},
-		gatewayLabels:      []string{"server_cluster", "server_name", "server_id", "server_gateway_name", "server_gateway_id"},
+		routeLabels:        []string{"server_cluster", "server_name", "server_id", "server_route_name", "server_route_name_idx"},
+		gatewayLabels:      []string{"server_cluster", "server_name", "server_id", "server_gateway_name", "server_gateway_name_idx"},
 		jsServerLabels:     []string{"server_id", "server_name", "cluster_name"},
 		jsServerInfoLabels: []string{"server_name", "server_host", "server_id", "server_cluster", "server_domain", "server_version", "server_jetstream"},
 		constLabels:        constLabels,
@@ -1013,6 +1033,14 @@ func (sc *StatzCollector) Collect(ch chan<- prometheus.Metric) {
 					}
 				}
 			}
+
+			pairs := make([]nameIDPair, len(sm.Stats.Routes))
+			for i, rs := range sm.Stats.Routes {
+				pairs[i].id = rs.ID
+				pairs[i].name = rs.Name
+			}
+			sc.routeIDRemap = remapIDToIdx(pairs, sc.routeIDRemap)
+
 			for _, rs := range sm.Stats.Routes {
 				labels = sc.routeLabelValues(sm, rs)
 				metrics.newGaugeMetric(sc.descs.RouteSentMsgs, float64(rs.Sent.Msgs), labels)
@@ -1022,6 +1050,13 @@ func (sc *StatzCollector) Collect(ch chan<- prometheus.Metric) {
 				metrics.newGaugeMetric(sc.descs.RoutePending, float64(rs.Pending), labels)
 			}
 
+			pairs = make([]nameIDPair, len(sm.Stats.Gateways))
+			for i, rs := range sm.Stats.Gateways {
+				pairs[i].id = rs.ID
+				pairs[i].name = rs.Name
+			}
+			sc.gatewayIDRemap = remapIDToIdx(pairs, sc.gatewayIDRemap)
+
 			for _, gw := range sm.Stats.Gateways {
 				labels = sc.gatewayLabelValues(sm, gw)
 				metrics.newGaugeMetric(sc.descs.GatewaySentMsgs, float64(gw.Sent.Msgs), labels)
@@ -1184,3 +1219,52 @@ func unmarshalMsg(msg *nats.Msg, v any) error {
 
 	return json.Unmarshal(data, v)
 }
+
+type nameIDPair struct {
+	name string
+	id   uint64
+}
+
+func remapIDToIdx(pairs []nameIDPair, existingMapping map[string]map[uint64]int) map[string]map[uint64]int {
+	newMapping := make(map[string]map[uint64]int)
+
+	// give existing the same idx
+	for _, rs := range pairs {
+		newByName, ok := newMapping[rs.name]
+		if !ok {
+			newByName = make(map[uint64]int)
+			newMapping[rs.name] = newByName
+		}
+
+		existingByName, ok := existingMapping[rs.name]
+		if !ok {
+			continue
+		}
+
+		idx, ok := existingByName[rs.id]
+		if !ok {
+			continue
+		}
+
+		newByName[rs.id] = idx
+	}
+
+	// assign new ones new idx
+	for _, path := range pairs {
+		newByName := newMapping[path.name]
+		_, ok := newByName[path.id]
+		if ok {
+			continue
+		}
+
+		vals := maps.Values(newByName)
+		for i := 0; i <= len(vals); i++ {
+			if !slices.Contains(vals, i) {
+				newByName[path.id] = i
+				break
+			}
+		}
+	}
+
+	return newMapping
+}

surveyor/collector_statz_test.go

@@ -0,0 +1,49 @@
+package surveyor
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestRemapIdToIdx(t *testing.T) {
+	existingMapping := map[string]map[uint64]int{
+		"a": {
+			100: 0,
+			200: 2,
+		},
+		"b": {
+			100: 0,
+		},
+	}
+
+	pairs := []nameIDPair{
+		{name: "a", id: 200},
+		{name: "a", id: 100},
+		{name: "a", id: 300},
+		{name: "a", id: 400},
+		{name: "b", id: 200},
+		{name: "c", id: 200},
+		{name: "c", id: 100},
+	}
+
+	newMapping := remapIDToIdx(pairs, existingMapping)
+	expected := map[string]map[uint64]int{
+		"a": {
+			100: 0,
+			200: 2,
+			300: 1,
+			400: 3,
+		},
+		"b": {
+			200: 0,
+		},
+		"c": {
+			200: 0,
+			100: 1,
+		},
+	}
+
+	if !reflect.DeepEqual(expected, newMapping) {
+		t.Fatalf("Invalid mapping config; want: %v; got: %v", expected, newMapping)
+	}
+}

surveyor/surveyor_test.go

@@ -150,11 +150,14 @@ func TestSurveyor_Basic(t *testing.T) {
 		if !strings.Contains(output, "server_gateway_name") {
 			t.Fatalf("invalid output, missing 'server_gateway_name':  %v\n", output)
 		}
-		if !strings.Contains(output, "server_gateway_id") {
-			t.Fatalf("invalid output, missing 'server_gateway_id':  %v\n", output)
+		if !strings.Contains(output, "server_gateway_name_idx") {
+			t.Fatalf("invalid output, missing 'server_gateway_name_idx':  %v\n", output)
 		}
-		if !strings.Contains(output, "server_route_id") {
-			t.Fatalf("invalid output, missing 'server_route_id':  %v\n", output)
+		if !strings.Contains(output, "server_route_name") {
+			t.Fatalf("invalid output, missing 'server_route_name':  %v\n", output)
+		}
+		if !strings.Contains(output, "server_route_name_idx") {
+			t.Fatalf("invalid output, missing 'server_route_name_idx':  %v\n", output)
 		}
 		if !strings.Contains(output, "nats_survey_surveyed_count 3") {
 			t.Fatalf("invalid output, missing 'nats_survey_surveyed_count 3':  %v\n", output)