metrics, cmd/geth: informational metrics (prometheus, influxdb, opentsb) (#24877)

This chang creates a GaugeInfo metrics type for registering informational (textual) metrics, e.g. geth version number. It also improves the testing for backend-exporters, and uses a shared subpackage in 'internal' to provide sample datasets and ordered registry. 

Implements #21783

---------

Co-authored-by: Martin Holst Swende <martin@swende.se>

metrics/influxdb/influxdb.go

@@ -32,6 +32,13 @@ func readMeter(namespace, name string, i interface{}) (string, map[string]interf
 			"value": metric.Snapshot().Value(),
 		}
 		return measurement, fields
+	case metrics.GaugeInfo:
+		ms := metric.Snapshot()
+		measurement := fmt.Sprintf("%s%s.gauge", namespace, name)
+		fields := map[string]interface{}{
+			"value": ms.Value().String(),
+		}
+		return measurement, fields
 	case metrics.Histogram:
 		ms := metric.Snapshot()
 		if ms.Count() <= 0 {

metrics/influxdb/influxdb_test.go

@@ -0,0 +1,114 @@
+// Copyright 2023 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package influxdb
+
+import (
+	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"os"
+	"strings"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/metrics"
+	"github.com/ethereum/go-ethereum/metrics/internal"
+	influxdb2 "github.com/influxdata/influxdb-client-go/v2"
+)
+
+func TestMain(m *testing.M) {
+	metrics.Enabled = true
+	os.Exit(m.Run())
+}
+
+func TestExampleV1(t *testing.T) {
+	r := internal.ExampleMetrics()
+	var have, want string
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		haveB, _ := io.ReadAll(r.Body)
+		have = string(haveB)
+		r.Body.Close()
+	}))
+	defer ts.Close()
+	u, _ := url.Parse(ts.URL)
+	rep := &reporter{
+		reg:       r,
+		url:       *u,
+		namespace: "goth.",
+	}
+	if err := rep.makeClient(); err != nil {
+		t.Fatal(err)
+	}
+	if err := rep.send(978307200); err != nil {
+		t.Fatal(err)
+	}
+	if wantB, err := os.ReadFile("./testdata/influxdbv1.want"); err != nil {
+		t.Fatal(err)
+	} else {
+		want = string(wantB)
+	}
+	if have != want {
+		t.Errorf("\nhave:\n%v\nwant:\n%v\n", have, want)
+		t.Logf("have vs want:\n%v", findFirstDiffPos(have, want))
+	}
+}
+
+func TestExampleV2(t *testing.T) {
+	r := internal.ExampleMetrics()
+	var have, want string
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		haveB, _ := io.ReadAll(r.Body)
+		have = string(haveB)
+		r.Body.Close()
+	}))
+	defer ts.Close()
+
+	rep := &v2Reporter{
+		reg:       r,
+		endpoint:  ts.URL,
+		namespace: "goth.",
+	}
+	rep.client = influxdb2.NewClient(rep.endpoint, rep.token)
+	defer rep.client.Close()
+	rep.write = rep.client.WriteAPI(rep.organization, rep.bucket)
+
+	rep.send(978307200)
+
+	if wantB, err := os.ReadFile("./testdata/influxdbv2.want"); err != nil {
+		t.Fatal(err)
+	} else {
+		want = string(wantB)
+	}
+	if have != want {
+		t.Errorf("\nhave:\n%v\nwant:\n%v\n", have, want)
+		t.Logf("have vs want:\n %v", findFirstDiffPos(have, want))
+	}
+}
+
+func findFirstDiffPos(a, b string) string {
+	yy := strings.Split(b, "\n")
+	for i, x := range strings.Split(a, "\n") {
+		if i >= len(yy) {
+			return fmt.Sprintf("have:%d: %s\nwant:%d: <EOF>", i, x, i)
+		}
+		if y := yy[i]; x != y {
+			return fmt.Sprintf("have:%d: %s\nwant:%d: %s", i, x, i, y)
+		}
+	}
+	return ""
+}

metrics/influxdb/influxdbv1.go

@@ -79,7 +79,7 @@ func InfluxDBWithTagsOnce(r metrics.Registry, url, database, username, password,
 		return fmt.Errorf("unable to make InfluxDB client. err: %v", err)
 	}
 
-	if err := rep.send(); err != nil {
+	if err := rep.send(0); err != nil {
 		return fmt.Errorf("unable to send to InfluxDB. err: %v", err)
 	}
 
@@ -107,7 +107,7 @@ func (r *reporter) run() {
 	for {
 		select {
 		case <-intervalTicker.C:
-			if err := r.send(); err != nil {
+			if err := r.send(0); err != nil {
 				log.Warn("Unable to send to InfluxDB", "err", err)
 			}
 		case <-pingTicker.C:
@@ -123,7 +123,9 @@ func (r *reporter) run() {
 	}
 }
 
-func (r *reporter) send() error {
+// send sends the measurements. If provided tstamp is >0, it is used. Otherwise,
+// a 'fresh' timestamp is used.
+func (r *reporter) send(tstamp int64) error {
 	bps, err := client.NewBatchPoints(
 		client.BatchPointsConfig{
 			Database: r.database,
@@ -132,7 +134,12 @@ func (r *reporter) send() error {
 		return err
 	}
 	r.reg.Each(func(name string, i interface{}) {
-		now := time.Now()
+		var now time.Time
+		if tstamp <= 0 {
+			now = time.Now()
+		} else {
+			now = time.Unix(tstamp, 0)
+		}
 		measurement, fields := readMeter(r.namespace, name, i)
 		if fields == nil {
 			return

metrics/influxdb/influxdbv2.go

@@ -64,7 +64,7 @@ func (r *v2Reporter) run() {
 	for {
 		select {
 		case <-intervalTicker.C:
-			r.send()
+			r.send(0)
 		case <-pingTicker.C:
 			_, err := r.client.Health(context.Background())
 			if err != nil {
@@ -74,9 +74,16 @@ func (r *v2Reporter) run() {
 	}
 }
 
-func (r *v2Reporter) send() {
+// send sends the measurements. If provided tstamp is >0, it is used. Otherwise,
+// a 'fresh' timestamp is used.
+func (r *v2Reporter) send(tstamp int64) {
 	r.reg.Each(func(name string, i interface{}) {
-		now := time.Now()
+		var now time.Time
+		if tstamp <= 0 {
+			now = time.Now()
+		} else {
+			now = time.Unix(tstamp, 0)
+		}
 		measurement, fields := readMeter(r.namespace, name, i)
 		if fields == nil {
 			return

metrics/influxdb/testdata/influxdbv1.want

@@ -0,0 +1,9 @@
+goth.test/counter.count value=12345 978307200000000000
+goth.test/counter_float64.count value=54321.98 978307200000000000
+goth.test/gauge.gauge value=23456i 978307200000000000
+goth.test/gauge_float64.gauge value=34567.89 978307200000000000
+goth.test/gauge_info.gauge value="{\"arch\":\"amd64\",\"commit\":\"7caa2d8163ae3132c1c2d6978c76610caee2d949\",\"os\":\"linux\",\"protocol_versions\":\"64 65 66\",\"version\":\"1.10.18-unstable\"}" 978307200000000000
+goth.test/histogram.histogram count=3i,max=3i,mean=2,min=1i,p25=1,p50=2,p75=3,p95=3,p99=3,p999=3,p9999=3,stddev=0.816496580927726,variance=0.6666666666666666 978307200000000000
+goth.test/meter.meter count=0i,m1=0,m15=0,m5=0,mean=0 978307200000000000
+goth.test/resetting_timer.span count=6i,max=120000000i,mean=30000000,min=10000000i,p50=12000000i,p95=120000000i,p99=120000000i 978307200000000000
+goth.test/timer.timer count=6i,m1=0,m15=0,m5=0,max=120000000i,mean=38333333.333333336,meanrate=0,min=20000000i,p50=22500000,p75=48000000,p95=120000000,p99=120000000,p999=120000000,p9999=120000000,stddev=36545253.529775314,variance=1335555555555555.2 978307200000000000

metrics/influxdb/testdata/influxdbv2.want

@@ -0,0 +1,9 @@
+goth.test/counter.count value=12345 978307200000000000
+goth.test/counter_float64.count value=54321.98 978307200000000000
+goth.test/gauge.gauge value=23456i 978307200000000000
+goth.test/gauge_float64.gauge value=34567.89 978307200000000000
+goth.test/gauge_info.gauge value="{\"arch\":\"amd64\",\"commit\":\"7caa2d8163ae3132c1c2d6978c76610caee2d949\",\"os\":\"linux\",\"protocol_versions\":\"64 65 66\",\"version\":\"1.10.18-unstable\"}" 978307200000000000
+goth.test/histogram.histogram count=3i,max=3i,mean=2,min=1i,p25=1,p50=2,p75=3,p95=3,p99=3,p999=3,p9999=3,stddev=0.816496580927726,variance=0.6666666666666666 978307200000000000
+goth.test/meter.meter count=0i,m1=0,m15=0,m5=0,mean=0 978307200000000000
+goth.test/resetting_timer.span count=6i,max=120000000i,mean=30000000,min=10000000i,p50=12000000i,p95=120000000i,p99=120000000i 978307200000000000
+goth.test/timer.timer count=6i,m1=0,m15=0,m5=0,max=120000000i,mean=38333333.333333336,meanrate=0,min=20000000i,p50=22500000,p75=48000000,p95=120000000,p99=120000000,p999=120000000,p9999=120000000,stddev=36545253.529775314,variance=1335555555555555.2 978307200000000000