node_exporter/collector/systemd_linux.go
Calle Pettersson 859a825bb8 Replace --collectors.enabled with per-collector flags (#640)
* Move NodeCollector into package collector

* Refactor collector enabling

* Update README with new collector enabled flags

* Fix out-of-date inline flag reference syntax

* Use new flags in end-to-end tests

* Add flag to disable all default collectors

* Track if a flag has been set explicitly

* Add --collectors.disable-defaults to README

* Revert disable-defaults flag

* Shorten flags

* Fixup timex collector registration

* Fix end-to-end tests

* Change procfs and sysfs path flags

* Fix review comments
2017-09-28 15:06:26 +02:00

154 lines
4.8 KiB
Go

// Copyright 2015 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 !nosystemd
package collector
import (
"fmt"
"regexp"
"github.com/coreos/go-systemd/dbus"
"github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/common/log"
"gopkg.in/alecthomas/kingpin.v2"
)
var (
unitWhitelist = kingpin.Flag("collector.systemd.unit-whitelist", "Regexp of systemd units to whitelist. Units must both match whitelist and not match blacklist to be included.").Default(".+").String()
unitBlacklist = kingpin.Flag("collector.systemd.unit-blacklist", "Regexp of systemd units to blacklist. Units must both match whitelist and not match blacklist to be included.").Default(".+\\.scope").String()
systemdPrivate = kingpin.Flag("collector.systemd.private", "Establish a private, direct connection to systemd without dbus.").Bool()
)
type systemdCollector struct {
unitDesc *prometheus.Desc
systemRunningDesc *prometheus.Desc
unitWhitelistPattern *regexp.Regexp
unitBlacklistPattern *regexp.Regexp
}
var unitStatesName = []string{"active", "activating", "deactivating", "inactive", "failed"}
func init() {
registerCollector("systemd", defaultDisabled, NewSystemdCollector)
}
// NewSystemdCollector returns a new Collector exposing systemd statistics.
func NewSystemdCollector() (Collector, error) {
const subsystem = "systemd"
unitDesc := prometheus.NewDesc(
prometheus.BuildFQName(namespace, subsystem, "unit_state"),
"Systemd unit", []string{"name", "state"}, nil,
)
systemRunningDesc := prometheus.NewDesc(
prometheus.BuildFQName(namespace, subsystem, "system_running"),
"Whether the system is operational (see 'systemctl is-system-running')",
nil, nil,
)
unitWhitelistPattern := regexp.MustCompile(fmt.Sprintf("^(?:%s)$", *unitWhitelist))
unitBlacklistPattern := regexp.MustCompile(fmt.Sprintf("^(?:%s)$", *unitBlacklist))
return &systemdCollector{
unitDesc: unitDesc,
systemRunningDesc: systemRunningDesc,
unitWhitelistPattern: unitWhitelistPattern,
unitBlacklistPattern: unitBlacklistPattern,
}, nil
}
func (c *systemdCollector) Update(ch chan<- prometheus.Metric) error {
units, err := c.listUnits()
if err != nil {
return fmt.Errorf("couldn't get units states: %s", err)
}
c.collectUnitStatusMetrics(ch, units)
systemState, err := c.getSystemState()
if err != nil {
return fmt.Errorf("couldn't get system state: %s", err)
}
c.collectSystemState(ch, systemState)
return nil
}
func (c *systemdCollector) collectUnitStatusMetrics(ch chan<- prometheus.Metric, units []dbus.UnitStatus) {
for _, unit := range units {
for _, stateName := range unitStatesName {
isActive := 0.0
if stateName == unit.ActiveState {
isActive = 1.0
}
ch <- prometheus.MustNewConstMetric(
c.unitDesc, prometheus.GaugeValue, isActive,
unit.Name, stateName)
}
}
}
func (c *systemdCollector) collectSystemState(ch chan<- prometheus.Metric, systemState string) {
isSystemRunning := 0.0
if systemState == `"running"` {
isSystemRunning = 1.0
}
ch <- prometheus.MustNewConstMetric(c.systemRunningDesc, prometheus.GaugeValue, isSystemRunning)
}
func (c *systemdCollector) newDbus() (*dbus.Conn, error) {
if *systemdPrivate {
return dbus.NewSystemdConnection()
}
return dbus.New()
}
func (c *systemdCollector) listUnits() ([]dbus.UnitStatus, error) {
conn, err := c.newDbus()
if err != nil {
return nil, fmt.Errorf("couldn't get dbus connection: %s", err)
}
allUnits, err := conn.ListUnits()
conn.Close()
if err != nil {
return []dbus.UnitStatus{}, err
}
units := filterUnits(allUnits, c.unitWhitelistPattern, c.unitBlacklistPattern)
return units, nil
}
func filterUnits(units []dbus.UnitStatus, whitelistPattern, blacklistPattern *regexp.Regexp) []dbus.UnitStatus {
filtered := make([]dbus.UnitStatus, 0, len(units))
for _, unit := range units {
if whitelistPattern.MatchString(unit.Name) && !blacklistPattern.MatchString(unit.Name) {
filtered = append(filtered, unit)
} else {
log.Debugf("Ignoring unit: %s", unit.Name)
}
}
return filtered
}
func (c *systemdCollector) getSystemState() (state string, err error) {
conn, err := c.newDbus()
if err != nil {
return "", fmt.Errorf("couldn't get dbus connection: %s", err)
}
state, err = conn.GetManagerProperty("SystemState")
conn.Close()
return state, err
}