From 31bc2a2434ed29b6cd020ee712722b4b865f32e1 Mon Sep 17 00:00:00 2001 From: Maxim Krasilnikov Date: Thu, 11 Apr 2019 12:56:19 +0300 Subject: [PATCH] metrics/prometheus: expose metrics in prometheus format too (#17077) * metrics/prometheus: added prometheus http server and metrics collector * metrics/prometheus: minor cleanups * metrics/prometheus: named keys instead name in tag * metrics/prometheus: minor typo cleanups, sorted report --- metrics/exp/exp.go | 2 + metrics/prometheus/collector.go | 115 +++++++++++++++++++++++++++++++ metrics/prometheus/prometheus.go | 68 ++++++++++++++++++ 3 files changed, 185 insertions(+) create mode 100644 metrics/prometheus/collector.go create mode 100644 metrics/prometheus/prometheus.go diff --git a/metrics/exp/exp.go b/metrics/exp/exp.go index 325a193c7..55820f1aa 100644 --- a/metrics/exp/exp.go +++ b/metrics/exp/exp.go @@ -9,6 +9,7 @@ import ( "sync" "github.com/ethereum/go-ethereum/metrics" + "github.com/ethereum/go-ethereum/metrics/prometheus" ) type exp struct { @@ -42,6 +43,7 @@ func Exp(r metrics.Registry) { // http.HandleFunc("/debug/vars", e.expHandler) // haven't found an elegant way, so just use a different endpoint http.Handle("/debug/metrics", h) + http.Handle("/debug/metrics/prometheus", prometheus.Handler(r)) } // ExpHandler will return an expvar powered metrics handler. diff --git a/metrics/prometheus/collector.go b/metrics/prometheus/collector.go new file mode 100644 index 000000000..8350fa2aa --- /dev/null +++ b/metrics/prometheus/collector.go @@ -0,0 +1,115 @@ +// Copyright 2019 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 . + +package prometheus + +import ( + "bytes" + "fmt" + "strconv" + "strings" + + "github.com/ethereum/go-ethereum/metrics" +) + +var ( + typeGaugeTpl = "# TYPE %s gauge\n" + typeCounterTpl = "# TYPE %s counter\n" + typeSummaryTpl = "# TYPE %s summary\n" + keyValueTpl = "%s %v\n\n" + keyQuantileTagValueTpl = "%s {quantile=\"%s\"} %v\n\n" +) + +// collector is a collection of byte buffers that aggregate Prometheus reports +// for different metric types. +type collector struct { + buff *bytes.Buffer +} + +// newCollector createa a new Prometheus metric aggregator. +func newCollector() *collector { + return &collector{ + buff: &bytes.Buffer{}, + } +} + +func (c *collector) addCounter(name string, m metrics.Counter) { + c.writeGaugeCounter(name, m.Count()) +} + +func (c *collector) addGauge(name string, m metrics.Gauge) { + c.writeGaugeCounter(name, m.Value()) +} + +func (c *collector) addGaugeFloat64(name string, m metrics.GaugeFloat64) { + c.writeGaugeCounter(name, m.Value()) +} + +func (c *collector) addHistogram(name string, m metrics.Histogram) { + pv := []float64{0.5, 0.75, 0.95, 0.99, 0.999, 0.9999} + ps := m.Percentiles(pv) + c.writeSummaryCounter(name, m.Count()) + for i := range pv { + c.writeSummaryPercentile(name, strconv.FormatFloat(pv[i], 'f', -1, 64), ps[i]) + } +} + +func (c *collector) addMeter(name string, m metrics.Meter) { + c.writeGaugeCounter(name, m.Count()) +} + +func (c *collector) addTimer(name string, m metrics.Timer) { + pv := []float64{0.5, 0.75, 0.95, 0.99, 0.999, 0.9999} + ps := m.Percentiles(pv) + c.writeSummaryCounter(name, m.Count()) + for i := range pv { + c.writeSummaryPercentile(name, strconv.FormatFloat(pv[i], 'f', -1, 64), ps[i]) + } +} + +func (c *collector) addResettingTimer(name string, m metrics.ResettingTimer) { + if len(m.Values()) <= 0 { + return + } + ps := m.Percentiles([]float64{50, 95, 99}) + val := m.Values() + c.writeSummaryCounter(name, len(val)) + c.writeSummaryPercentile(name, "0.50", ps[0]) + c.writeSummaryPercentile(name, "0.95", ps[1]) + c.writeSummaryPercentile(name, "0.99", ps[2]) +} + +func (c *collector) writeGaugeCounter(name string, value interface{}) { + name = mutateKey(name) + c.buff.WriteString(fmt.Sprintf(typeGaugeTpl, name)) + c.buff.WriteString(fmt.Sprintf(keyValueTpl, name, value)) +} + +func (c *collector) writeSummaryCounter(name string, value interface{}) { + name = mutateKey(name + "_count") + c.buff.WriteString(fmt.Sprintf(typeCounterTpl, name)) + c.buff.WriteString(fmt.Sprintf(keyValueTpl, name, value)) +} + +func (c *collector) writeSummaryPercentile(name, p string, value interface{}) { + name = mutateKey(name) + c.buff.WriteString(fmt.Sprintf(typeSummaryTpl, name)) + c.buff.WriteString(fmt.Sprintf(keyQuantileTagValueTpl, name, p, value)) +} + +func mutateKey(key string) string { + return strings.Replace(key, "/", "_", -1) +} diff --git a/metrics/prometheus/prometheus.go b/metrics/prometheus/prometheus.go new file mode 100644 index 000000000..9ad5ec7e9 --- /dev/null +++ b/metrics/prometheus/prometheus.go @@ -0,0 +1,68 @@ +// Copyright 2019 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 . + +// Package prometheus exposes go-metrics into a Prometheus format. +package prometheus + +import ( + "fmt" + "net/http" + "sort" + + "github.com/ethereum/go-ethereum/log" + "github.com/ethereum/go-ethereum/metrics" +) + +// Handler returns an HTTP handler which dump metrics in Prometheus format. +func Handler(reg metrics.Registry) http.Handler { + return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { + // Gather and pre-sort the metrics to avoid random listings + var names []string + reg.Each(func(name string, i interface{}) { + names = append(names, name) + }) + sort.Strings(names) + + // Aggregate all the metris into a Prometheus collector + c := newCollector() + + for _, name := range names { + i := reg.Get(name) + + switch m := i.(type) { + case metrics.Counter: + c.addCounter(name, m.Snapshot()) + case metrics.Gauge: + c.addGauge(name, m.Snapshot()) + case metrics.GaugeFloat64: + c.addGaugeFloat64(name, m.Snapshot()) + case metrics.Histogram: + c.addHistogram(name, m.Snapshot()) + case metrics.Meter: + c.addMeter(name, m.Snapshot()) + case metrics.Timer: + c.addTimer(name, m.Snapshot()) + case metrics.ResettingTimer: + c.addResettingTimer(name, m.Snapshot()) + default: + log.Warn("Unknown Prometheus metric type", "type", fmt.Sprintf("%T", i)) + } + } + w.Header().Add("Content-Type", "text/plain") + w.Header().Add("Content-Length", fmt.Sprint(c.buff.Len())) + w.Write(c.buff.Bytes()) + }) +}