Skip to content

Commit

Permalink
Add collector for database/sql#DBStats (#866)
Browse files Browse the repository at this point in the history
* Add collector for database/sql#DBStats

Signed-off-by: Mitsuo Heijo <mitsuo.heijo@gmail.com>
  • Loading branch information
johejo authored May 20, 2021
1 parent b89620c commit a66da1d
Show file tree
Hide file tree
Showing 4 changed files with 283 additions and 0 deletions.
102 changes: 102 additions & 0 deletions prometheus/collectors/dbstats_collector.go
Original file line number Diff line number Diff line change
@@ -0,0 +1,102 @@
// Copyright 2021 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package collectors

import (
"database/sql"

"github.com/prometheus/client_golang/prometheus"
)

type dbStatsCollector struct {
db *sql.DB

maxOpenConnections *prometheus.Desc

openConnections *prometheus.Desc
inUseConnections *prometheus.Desc
idleConnections *prometheus.Desc

waitCount *prometheus.Desc
waitDuration *prometheus.Desc
maxIdleClosed *prometheus.Desc
maxIdleTimeClosed *prometheus.Desc
maxLifetimeClosed *prometheus.Desc
}

// NewDBStatsCollector returns a collector that exports metrics about the given *sql.DB.
// See https://golang.org/pkg/database/sql/#DBStats for more information on stats.
func NewDBStatsCollector(db *sql.DB, dbName string) prometheus.Collector {
fqName := func(name string) string {
return "go_sql_" + name
}
return &dbStatsCollector{
db: db,
maxOpenConnections: prometheus.NewDesc(
fqName("max_open_connections"),
"Maximum number of open connections to the database.",
nil, prometheus.Labels{"db_name": dbName},
),
openConnections: prometheus.NewDesc(
fqName("open_connections"),
"The number of established connections both in use and idle.",
nil, prometheus.Labels{"db_name": dbName},
),
inUseConnections: prometheus.NewDesc(
fqName("in_use_connections"),
"The number of connections currently in use.",
nil, prometheus.Labels{"db_name": dbName},
),
idleConnections: prometheus.NewDesc(
fqName("idle_connections"),
"The number of idle connections.",
nil, prometheus.Labels{"db_name": dbName},
),
waitCount: prometheus.NewDesc(
fqName("wait_count_total"),
"The total number of connections waited for.",
nil, prometheus.Labels{"db_name": dbName},
),
waitDuration: prometheus.NewDesc(
fqName("wait_duration_seconds_total"),
"The total time blocked waiting for a new connection.",
nil, prometheus.Labels{"db_name": dbName},
),
maxIdleClosed: prometheus.NewDesc(
fqName("max_idle_closed_total"),
"The total number of connections closed due to SetMaxIdleConns.",
nil, prometheus.Labels{"db_name": dbName},
),
maxIdleTimeClosed: prometheus.NewDesc(
fqName("max_idle_time_closed_total"),
"The total number of connections closed due to SetConnMaxIdleTime.",
nil, prometheus.Labels{"db_name": dbName},
),
maxLifetimeClosed: prometheus.NewDesc(
fqName("max_lifetime_closed_total"),
"The total number of connections closed due to SetConnMaxLifetime.",
nil, prometheus.Labels{"db_name": dbName},
),
}
}

// Describe implements Collector.
func (c *dbStatsCollector) Describe(ch chan<- *prometheus.Desc) {
c.describe(ch)
}

// Collect implements Collector.
func (c *dbStatsCollector) Collect(ch chan<- prometheus.Metric) {
c.collect(ch)
}
43 changes: 43 additions & 0 deletions prometheus/collectors/dbstats_collector_go115.go
Original file line number Diff line number Diff line change
@@ -0,0 +1,43 @@
// Copyright 2021 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// +build go1.15

package collectors

import "github.com/prometheus/client_golang/prometheus"

func (c *dbStatsCollector) describe(ch chan<- *prometheus.Desc) {
ch <- c.maxOpenConnections
ch <- c.openConnections
ch <- c.inUseConnections
ch <- c.idleConnections
ch <- c.waitCount
ch <- c.waitDuration
ch <- c.maxIdleClosed
ch <- c.maxIdleTimeClosed
ch <- c.maxLifetimeClosed
}

func (c *dbStatsCollector) collect(ch chan<- prometheus.Metric) {
stats := c.db.Stats()
ch <- prometheus.MustNewConstMetric(c.maxOpenConnections, prometheus.GaugeValue, float64(stats.MaxOpenConnections))
ch <- prometheus.MustNewConstMetric(c.openConnections, prometheus.GaugeValue, float64(stats.OpenConnections))
ch <- prometheus.MustNewConstMetric(c.inUseConnections, prometheus.GaugeValue, float64(stats.InUse))
ch <- prometheus.MustNewConstMetric(c.idleConnections, prometheus.GaugeValue, float64(stats.Idle))
ch <- prometheus.MustNewConstMetric(c.waitCount, prometheus.CounterValue, float64(stats.WaitCount))
ch <- prometheus.MustNewConstMetric(c.waitDuration, prometheus.CounterValue, stats.WaitDuration.Seconds())
ch <- prometheus.MustNewConstMetric(c.maxIdleClosed, prometheus.CounterValue, float64(stats.MaxIdleClosed))
ch <- prometheus.MustNewConstMetric(c.maxIdleTimeClosed, prometheus.CounterValue, float64(stats.MaxIdleTimeClosed))
ch <- prometheus.MustNewConstMetric(c.maxLifetimeClosed, prometheus.CounterValue, float64(stats.MaxLifetimeClosed))
}
41 changes: 41 additions & 0 deletions prometheus/collectors/dbstats_collector_pre_go115.go
Original file line number Diff line number Diff line change
@@ -0,0 +1,41 @@
// Copyright 2021 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// +build !go1.15

package collectors

import "github.com/prometheus/client_golang/prometheus"

func (c *dbStatsCollector) describe(ch chan<- *prometheus.Desc) {
ch <- c.maxOpenConnections
ch <- c.openConnections
ch <- c.inUseConnections
ch <- c.idleConnections
ch <- c.waitCount
ch <- c.waitDuration
ch <- c.maxIdleClosed
ch <- c.maxLifetimeClosed
}

func (c *dbStatsCollector) collect(ch chan<- prometheus.Metric) {
stats := c.db.Stats()
ch <- prometheus.MustNewConstMetric(c.maxOpenConnections, prometheus.GaugeValue, float64(stats.MaxOpenConnections))
ch <- prometheus.MustNewConstMetric(c.openConnections, prometheus.GaugeValue, float64(stats.OpenConnections))
ch <- prometheus.MustNewConstMetric(c.inUseConnections, prometheus.GaugeValue, float64(stats.InUse))
ch <- prometheus.MustNewConstMetric(c.idleConnections, prometheus.GaugeValue, float64(stats.Idle))
ch <- prometheus.MustNewConstMetric(c.waitCount, prometheus.CounterValue, float64(stats.WaitCount))
ch <- prometheus.MustNewConstMetric(c.waitDuration, prometheus.CounterValue, stats.WaitDuration.Seconds())
ch <- prometheus.MustNewConstMetric(c.maxIdleClosed, prometheus.CounterValue, float64(stats.MaxIdleClosed))
ch <- prometheus.MustNewConstMetric(c.maxLifetimeClosed, prometheus.CounterValue, float64(stats.MaxLifetimeClosed))
}
97 changes: 97 additions & 0 deletions prometheus/collectors/dbstats_collector_test.go
Original file line number Diff line number Diff line change
@@ -0,0 +1,97 @@
// Copyright 2021 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package collectors

import (
"database/sql"
"runtime"
"testing"

"github.com/prometheus/client_golang/prometheus"
)

func TestDBStatsCollector(t *testing.T) {
reg := prometheus.NewRegistry()
{
db := new(sql.DB)
if err := reg.Register(NewDBStatsCollector(db, "db_A")); err != nil {
t.Fatal(err)
}
}
{
db := new(sql.DB)
if err := reg.Register(NewDBStatsCollector(db, "db_B")); err != nil {
t.Fatal(err)
}
}

mfs, err := reg.Gather()
if err != nil {
t.Fatal(err)
}

names := []string{
"go_sql_max_open_connections",
"go_sql_open_connections",
"go_sql_in_use_connections",
"go_sql_idle_connections",
"go_sql_wait_count_total",
"go_sql_wait_duration_seconds_total",
"go_sql_max_idle_closed_total",
"go_sql_max_lifetime_closed_total",
}
if runtime.Version() >= "go1.15" {
names = append(names, "go_sql_max_idle_time_closed_total")
}
type result struct {
found bool
}
results := make(map[string]result)
for _, name := range names {
results[name] = result{found: false}
}
for _, mf := range mfs {
m := mf.GetMetric()
if len(m) != 2 {
t.Errorf("expected 2 metrics bug got %d", len(m))
}
labelA := m[0].GetLabel()[0]
if name := labelA.GetName(); name != "db_name" {
t.Errorf("expected to get label \"db_name\" but got %s", name)
}
if value := labelA.GetValue(); value != "db_A" {
t.Errorf("expected to get value \"db_A\" but got %s", value)
}
labelB := m[1].GetLabel()[0]
if name := labelB.GetName(); name != "db_name" {
t.Errorf("expected to get label \"db_name\" but got %s", name)
}
if value := labelB.GetValue(); value != "db_B" {
t.Errorf("expected to get value \"db_B\" but got %s", value)
}

for _, name := range names {
if name == mf.GetName() {
results[name] = result{found: true}
break
}
}
}

for name, result := range results {
if !result.found {
t.Errorf("%s not found", name)
}
}
}

0 comments on commit a66da1d

Please sign in to comment.