Move collector logic from main to separate package (#26)
Co-authored-by: Robert Fratto <robertfratto@gmail.com>
This commit is contained in:
Marc Tudurí
GitHub
parent
e3caa1dcf7
commit
44b1448080
5
.github/workflows/go.yml
vendored
5
.github/workflows/go.yml
vendored
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@ -21,11 +21,10 @@ jobs:
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run: go install github.com/google/dnsmasq_exporter
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- name: build tests
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run: go test -c
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run: go test -c ./collector
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- name: docker build
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run: docker build --pull --no-cache --rm -t=dns -f travis/Dockerfile .
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- name: run tests in docker
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run: docker run -v $PWD:/usr/src:ro dns /bin/sh -c './dnsmasq_exporter.test -test.v'
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run: docker run -v $PWD:/usr/src:ro -e TESTDATA_FILE_PATH=/usr/src/collector/testdata/dnsmasq.leases dns /bin/sh -c './collector.test -test.v'
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301
collector/collector.go
Normal file
301
collector/collector.go
Normal file
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@ -0,0 +1,301 @@
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// Copyright 2016 Google Inc. All Rights Reserved.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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// Package collector collects dnsmasq statistics as a Prometheus collector.
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package collector
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import (
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"bufio"
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"fmt"
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"log"
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"os"
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"strconv"
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"strings"
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"github.com/miekg/dns"
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"github.com/prometheus/client_golang/prometheus"
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"golang.org/x/sync/errgroup"
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)
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var (
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// floatMetrics contains prometheus Gauges, keyed by the stats DNS record
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// they correspond to.
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floatMetrics = map[string]*prometheus.Desc{
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"cachesize.bind.": prometheus.NewDesc(
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"dnsmasq_cachesize",
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"configured size of the DNS cache",
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nil, nil,
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),
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"insertions.bind.": prometheus.NewDesc(
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"dnsmasq_insertions",
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"DNS cache insertions",
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nil, nil,
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),
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"evictions.bind.": prometheus.NewDesc(
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"dnsmasq_evictions",
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"DNS cache exictions: numbers of entries which replaced an unexpired cache entry",
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nil, nil,
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),
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"misses.bind.": prometheus.NewDesc(
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"dnsmasq_misses",
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"DNS cache misses: queries which had to be forwarded",
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nil, nil,
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),
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"hits.bind.": prometheus.NewDesc(
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"dnsmasq_hits",
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"DNS queries answered locally (cache hits)",
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nil, nil,
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),
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"auth.bind.": prometheus.NewDesc(
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"dnsmasq_auth",
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"DNS queries for authoritative zones",
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nil, nil,
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),
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}
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serversMetrics = map[string]*prometheus.Desc{
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"queries": prometheus.NewDesc(
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"dnsmasq_servers_queries",
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"DNS queries on upstream server",
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[]string{"server"}, nil,
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),
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"queries_failed": prometheus.NewDesc(
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"dnsmasq_servers_queries_failed",
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"DNS queries failed on upstream server",
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[]string{"server"}, nil,
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),
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}
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// individual lease metrics have high cardinality and are thus disabled by
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// default, unless enabled with the -expose_leases flag
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leaseMetrics = prometheus.NewDesc(
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"dnsmasq_lease_expiry",
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"Expiry time for active DHCP leases",
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[]string{"mac_addr", "ip_addr", "computer_name", "client_id"},
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nil,
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)
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leases = prometheus.NewDesc(
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"dnsmasq_leases",
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"Number of DHCP leases handed out",
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nil, nil,
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)
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)
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// From https://manpages.debian.org/stretch/dnsmasq-base/dnsmasq.8.en.html:
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// The cache statistics are also available in the DNS as answers to queries of
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// class CHAOS and type TXT in domain bind. The domain names are cachesize.bind,
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// insertions.bind, evictions.bind, misses.bind, hits.bind, auth.bind and
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// servers.bind. An example command to query this, using the dig utility would
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// be:
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// dig +short chaos txt cachesize.bind
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// Config contains the configuration for the collector.
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type Config struct {
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DnsClient *dns.Client
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DnsmasqAddr string
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LeasesPath string
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ExposeLeases bool
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}
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// Collector implements prometheus.Collector and exposes dnsmasq metrics.
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type Collector struct {
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cfg Config
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}
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type lease struct {
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expiry uint64
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macAddress string
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ipAddress string
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computerName string
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clientId string
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}
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// New creates a new Collector.
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func New(cfg Config) *Collector {
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return &Collector{
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cfg: cfg,
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}
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}
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func (c *Collector) Describe(ch chan<- *prometheus.Desc) {
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for _, d := range floatMetrics {
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ch <- d
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}
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for _, d := range serversMetrics {
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ch <- d
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}
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ch <- leases
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ch <- leaseMetrics
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}
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func (c *Collector) Collect(ch chan<- prometheus.Metric) {
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var eg errgroup.Group
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eg.Go(func() error {
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msg := &dns.Msg{
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MsgHdr: dns.MsgHdr{
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Id: dns.Id(),
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RecursionDesired: true,
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},
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Question: []dns.Question{
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question("cachesize.bind."),
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question("insertions.bind."),
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question("evictions.bind."),
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question("misses.bind."),
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question("hits.bind."),
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question("auth.bind."),
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question("servers.bind."),
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},
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}
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in, _, err := c.cfg.DnsClient.Exchange(msg, c.cfg.DnsmasqAddr)
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if err != nil {
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return err
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}
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for _, a := range in.Answer {
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txt, ok := a.(*dns.TXT)
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if !ok {
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continue
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}
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switch txt.Hdr.Name {
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case "servers.bind.":
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for _, str := range txt.Txt {
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arr := strings.Fields(str)
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if got, want := len(arr), 3; got != want {
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return fmt.Errorf("stats DNS record servers.bind.: unexpeced number of argument in record: got %d, want %d", got, want)
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}
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queries, err := strconv.ParseFloat(arr[1], 64)
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if err != nil {
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return err
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}
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failedQueries, err := strconv.ParseFloat(arr[2], 64)
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if err != nil {
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return err
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}
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ch <- prometheus.MustNewConstMetric(serversMetrics["queries"], prometheus.GaugeValue, queries, arr[0])
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ch <- prometheus.MustNewConstMetric(serversMetrics["queries_failed"], prometheus.GaugeValue, failedQueries, arr[0])
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}
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default:
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g, ok := floatMetrics[txt.Hdr.Name]
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if !ok {
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continue // ignore unexpected answer from dnsmasq
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}
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if got, want := len(txt.Txt), 1; got != want {
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return fmt.Errorf("stats DNS record %q: unexpected number of replies: got %d, want %d", txt.Hdr.Name, got, want)
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}
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f, err := strconv.ParseFloat(txt.Txt[0], 64)
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if err != nil {
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return err
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}
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ch <- prometheus.MustNewConstMetric(g, prometheus.GaugeValue, f)
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}
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}
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return nil
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})
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eg.Go(func() error {
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activeLeases, err := readLeaseFile(c.cfg.LeasesPath)
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if err != nil {
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return err
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}
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ch <- prometheus.MustNewConstMetric(leases, prometheus.GaugeValue, float64(len(activeLeases)))
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if c.cfg.ExposeLeases {
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for _, activeLease := range activeLeases {
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ch <- prometheus.MustNewConstMetric(leaseMetrics, prometheus.GaugeValue, float64(activeLease.expiry),
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activeLease.macAddress, activeLease.ipAddress, activeLease.computerName, activeLease.clientId)
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}
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}
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return nil
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})
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if err := eg.Wait(); err != nil {
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log.Printf("could not complete scrape: %v", err)
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}
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}
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func question(name string) dns.Question {
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return dns.Question{
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Name: name,
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Qtype: dns.TypeTXT,
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Qclass: dns.ClassCHAOS,
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}
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}
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func parseLease(line string) (*lease, error) {
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arr := strings.Fields(line)
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if got, want := len(arr), 5; got != want {
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return nil, fmt.Errorf("illegal lease: expected %d fields, got %d", want, got)
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}
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expires, err := strconv.ParseUint(arr[0], 10, 64)
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if err != nil {
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return nil, err
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}
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return &lease{
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expiry: expires,
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macAddress: arr[1],
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ipAddress: arr[2],
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computerName: arr[3],
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clientId: arr[4],
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}, nil
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}
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// Read the DHCP lease file with the given path and return a list of leases.
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//
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// The format of the DHCP lease file written by dnsmasq is not formally
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// documented in the dnsmasq manual but the format has been described in the
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// mailing list:
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//
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// - https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2006q2/000733.html
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// - https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2016q2/010595.html
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//
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// The DHCP lease file is written to by lease_update_file() in
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// src/lease.c, and is read by lease_init().
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func readLeaseFile(path string) ([]lease, error) {
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f, err := os.Open(path)
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if err != nil {
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if os.IsNotExist(err) {
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// ignore
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return []lease{}, nil
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}
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return nil, err
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}
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defer f.Close()
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scanner := bufio.NewScanner(f)
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activeLeases := []lease{}
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for scanner.Scan() {
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activeLease, err := parseLease(scanner.Text())
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if err != nil {
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return nil, err
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}
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activeLeases = append(activeLeases, *activeLease)
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}
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if err := scanner.Err(); err != nil {
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return nil, err
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}
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return activeLeases, nil
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}
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@ -1,4 +1,18 @@
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package main
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// Copyright 2016 Google Inc. All Rights Reserved.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package collector
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import (
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"fmt"
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@ -13,6 +27,7 @@ import (
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"time"
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"github.com/miekg/dns"
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"github.com/prometheus/client_golang/prometheus"
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"github.com/prometheus/client_golang/prometheus/promhttp"
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)
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@ -60,18 +75,24 @@ func TestDnsmasqExporter(t *testing.T) {
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time.Sleep(10 * time.Millisecond) // do not hog the CPU
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}
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s := &server{
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promHandler: promhttp.Handler(),
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dnsClient: &dns.Client{
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SingleInflight: true,
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},
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dnsmasqAddr: "localhost:" + port,
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leasesPath: "testdata/dnsmasq.leases",
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exposeLeases: false,
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testDataFilePath := os.Getenv("TESTDATA_FILE_PATH")
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if testDataFilePath == "" {
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testDataFilePath = "./testdata/dnsmasq.leases"
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}
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cfg := Config{
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DnsClient: &dns.Client{
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SingleInflight: true,
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},
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DnsmasqAddr: "localhost:" + port,
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LeasesPath: testDataFilePath,
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ExposeLeases: false,
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}
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c := New(cfg)
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t.Run("first", func(t *testing.T) {
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metrics := fetchMetrics(t, s)
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metrics := fetchMetrics(t, c)
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want := map[string]string{
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"dnsmasq_leases": "2",
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"dnsmasq_cachesize": "666",
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@ -86,7 +107,7 @@ func TestDnsmasqExporter(t *testing.T) {
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})
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t.Run("second", func(t *testing.T) {
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metrics := fetchMetrics(t, s)
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metrics := fetchMetrics(t, c)
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want := map[string]string{
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"dnsmasq_leases": "2",
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"dnsmasq_cachesize": "666",
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@ -108,7 +129,7 @@ func TestDnsmasqExporter(t *testing.T) {
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}
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t.Run("after query", func(t *testing.T) {
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metrics := fetchMetrics(t, s)
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metrics := fetchMetrics(t, c)
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want := map[string]string{
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"dnsmasq_leases": "2",
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"dnsmasq_cachesize": "666",
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@ -123,7 +144,7 @@ func TestDnsmasqExporter(t *testing.T) {
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})
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t.Run("should not expose lease information when disabled", func(t *testing.T) {
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metrics := fetchMetrics(t, s)
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metrics := fetchMetrics(t, c)
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for key, _ := range metrics {
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if strings.Contains(key, "dnsmasq_lease_expiry") {
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t.Errorf("lease information should not be exposed when disabled: %v", key)
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@ -131,10 +152,10 @@ func TestDnsmasqExporter(t *testing.T) {
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}
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})
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s.exposeLeases = true
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c.cfg.ExposeLeases = true
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t.Run("with high-cardinality lease metrics enabled", func(t *testing.T) {
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metrics := fetchMetrics(t, s)
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metrics := fetchMetrics(t, c)
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want := map[string]string{
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"dnsmasq_leases": "2",
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"dnsmasq_cachesize": "666",
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@ -150,10 +171,10 @@ func TestDnsmasqExporter(t *testing.T) {
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}
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})
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s.leasesPath = "testdata/dnsmasq.leases.does.not.exists"
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c.cfg.LeasesPath = "testdata/dnsmasq.leases.does.not.exists"
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t.Run("without leases file", func(t *testing.T) {
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metrics := fetchMetrics(t, s)
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metrics := fetchMetrics(t, c)
|
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want := map[string]string{
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"dnsmasq_leases": "0",
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"dnsmasq_cachesize": "666",
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@ -169,9 +190,13 @@ func TestDnsmasqExporter(t *testing.T) {
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}
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func fetchMetrics(t *testing.T, s *server) map[string]string {
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func fetchMetrics(t *testing.T, c *Collector) map[string]string {
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reg := prometheus.NewRegistry()
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reg.MustRegister(c)
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handler := promhttp.HandlerFor(reg, promhttp.HandlerOpts{})
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|
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rec := httptest.NewRecorder()
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s.metrics(rec, httptest.NewRequest("GET", "/metrics", nil))
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handler.ServeHTTP(rec, httptest.NewRequest("GET", "/metrics", nil))
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resp := rec.Result()
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if got, want := resp.StatusCode, http.StatusOK; got != want {
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b, _ := ioutil.ReadAll(resp.Body)
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302
dnsmasq.go
302
dnsmasq.go
|
|
@ -16,17 +16,11 @@
|
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package main
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|
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import (
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"bufio"
|
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"flag"
|
||||
"fmt"
|
||||
"log"
|
||||
"net/http"
|
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"os"
|
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"strconv"
|
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"strings"
|
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|
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"golang.org/x/sync/errgroup"
|
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|
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"github.com/google/dnsmasq_exporter/collector"
|
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"github.com/miekg/dns"
|
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"github.com/prometheus/client_golang/prometheus"
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"github.com/prometheus/client_golang/prometheus/promhttp"
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|
|
@ -53,286 +47,33 @@ var (
|
|||
"path under which metrics are served")
|
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)
|
||||
|
||||
var (
|
||||
// floatMetrics contains prometheus Gauges, keyed by the stats DNS record
|
||||
// they correspond to.
|
||||
floatMetrics = map[string]prometheus.Gauge{
|
||||
"cachesize.bind.": prometheus.NewGauge(prometheus.GaugeOpts{
|
||||
Name: "dnsmasq_cachesize",
|
||||
Help: "configured size of the DNS cache",
|
||||
}),
|
||||
|
||||
"insertions.bind.": prometheus.NewGauge(prometheus.GaugeOpts{
|
||||
Name: "dnsmasq_insertions",
|
||||
Help: "DNS cache insertions",
|
||||
}),
|
||||
|
||||
"evictions.bind.": prometheus.NewGauge(prometheus.GaugeOpts{
|
||||
Name: "dnsmasq_evictions",
|
||||
Help: "DNS cache exictions: numbers of entries which replaced an unexpired cache entry",
|
||||
}),
|
||||
|
||||
"misses.bind.": prometheus.NewGauge(prometheus.GaugeOpts{
|
||||
Name: "dnsmasq_misses",
|
||||
Help: "DNS cache misses: queries which had to be forwarded",
|
||||
}),
|
||||
|
||||
"hits.bind.": prometheus.NewGauge(prometheus.GaugeOpts{
|
||||
Name: "dnsmasq_hits",
|
||||
Help: "DNS queries answered locally (cache hits)",
|
||||
}),
|
||||
|
||||
"auth.bind.": prometheus.NewGauge(prometheus.GaugeOpts{
|
||||
Name: "dnsmasq_auth",
|
||||
Help: "DNS queries for authoritative zones",
|
||||
}),
|
||||
}
|
||||
|
||||
serversMetrics = map[string]*prometheus.GaugeVec{
|
||||
"queries": prometheus.NewGaugeVec(
|
||||
prometheus.GaugeOpts{
|
||||
Name: "dnsmasq_servers_queries",
|
||||
Help: "DNS queries on upstream server",
|
||||
},
|
||||
[]string{"server"},
|
||||
),
|
||||
"queries_failed": prometheus.NewGaugeVec(
|
||||
prometheus.GaugeOpts{
|
||||
Name: "dnsmasq_servers_queries_failed",
|
||||
Help: "DNS queries failed on upstream server",
|
||||
},
|
||||
[]string{"server"},
|
||||
),
|
||||
}
|
||||
|
||||
// individual lease metrics have high cardinality and are thus disabled by
|
||||
// default, unless enabled with the -expose_leases flag
|
||||
leaseMetrics = prometheus.NewGaugeVec(
|
||||
prometheus.GaugeOpts{
|
||||
Name: "dnsmasq_lease_expiry",
|
||||
Help: "Expiry time for active DHCP leases",
|
||||
},
|
||||
[]string{"mac_addr", "ip_addr", "computer_name", "client_id"},
|
||||
)
|
||||
|
||||
leases = prometheus.NewGauge(prometheus.GaugeOpts{
|
||||
Name: "dnsmasq_leases",
|
||||
Help: "Number of DHCP leases handed out",
|
||||
})
|
||||
)
|
||||
|
||||
func init() {
|
||||
for _, g := range floatMetrics {
|
||||
prometheus.MustRegister(g)
|
||||
}
|
||||
for _, g := range serversMetrics {
|
||||
prometheus.MustRegister(g)
|
||||
}
|
||||
prometheus.MustRegister(leases)
|
||||
prometheus.MustRegister(leaseMetrics)
|
||||
prometheus.MustRegister(version.NewCollector("dnsmasq_exporter"))
|
||||
}
|
||||
|
||||
// From https://manpages.debian.org/stretch/dnsmasq-base/dnsmasq.8.en.html:
|
||||
// The cache statistics are also available in the DNS as answers to queries of
|
||||
// class CHAOS and type TXT in domain bind. The domain names are cachesize.bind,
|
||||
// insertions.bind, evictions.bind, misses.bind, hits.bind, auth.bind and
|
||||
// servers.bind. An example command to query this, using the dig utility would
|
||||
// be:
|
||||
// dig +short chaos txt cachesize.bind
|
||||
|
||||
type server struct {
|
||||
promHandler http.Handler
|
||||
dnsClient *dns.Client
|
||||
dnsmasqAddr string
|
||||
leasesPath string
|
||||
exposeLeases bool
|
||||
}
|
||||
|
||||
type lease struct {
|
||||
expiry uint64
|
||||
macAddress string
|
||||
ipAddress string
|
||||
computerName string
|
||||
clientId string
|
||||
}
|
||||
|
||||
func question(name string) dns.Question {
|
||||
return dns.Question{
|
||||
Name: name,
|
||||
Qtype: dns.TypeTXT,
|
||||
Qclass: dns.ClassCHAOS,
|
||||
}
|
||||
}
|
||||
|
||||
func parseLease(line string) (*lease, error) {
|
||||
arr := strings.Fields(line)
|
||||
if got, want := len(arr), 5; got != want {
|
||||
return nil, fmt.Errorf("illegal lease: expected %d fields, got %d", want, got)
|
||||
}
|
||||
|
||||
expires, err := strconv.ParseUint(arr[0], 10, 64)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &lease{
|
||||
expiry: expires,
|
||||
macAddress: arr[1],
|
||||
ipAddress: arr[2],
|
||||
computerName: arr[3],
|
||||
clientId: arr[4],
|
||||
}, nil
|
||||
}
|
||||
|
||||
// Read the DHCP lease file with the given path and return a list of leases.
|
||||
//
|
||||
// The format of the DHCP lease file written by dnsmasq is not formally
|
||||
// documented in the dnsmasq manual but the format has been described in the
|
||||
// mailing list:
|
||||
//
|
||||
// - https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2006q2/000733.html
|
||||
// - https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2016q2/010595.html
|
||||
//
|
||||
// The DHCP lease file is written to by lease_update_file() in
|
||||
// src/lease.c, and is read by lease_init().
|
||||
func readLeaseFile(path string) ([]lease, error) {
|
||||
f, err := os.Open(path)
|
||||
if err != nil {
|
||||
if os.IsNotExist(err) {
|
||||
// ignore
|
||||
return []lease{}, nil
|
||||
}
|
||||
|
||||
return nil, err
|
||||
}
|
||||
|
||||
defer f.Close()
|
||||
|
||||
scanner := bufio.NewScanner(f)
|
||||
activeLeases := []lease{}
|
||||
for scanner.Scan() {
|
||||
activeLease, err := parseLease(scanner.Text())
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
activeLeases = append(activeLeases, *activeLease)
|
||||
}
|
||||
|
||||
if err := scanner.Err(); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return activeLeases, nil
|
||||
}
|
||||
|
||||
func (s *server) metrics(w http.ResponseWriter, r *http.Request) {
|
||||
var eg errgroup.Group
|
||||
|
||||
eg.Go(func() error {
|
||||
msg := &dns.Msg{
|
||||
MsgHdr: dns.MsgHdr{
|
||||
Id: dns.Id(),
|
||||
RecursionDesired: true,
|
||||
},
|
||||
Question: []dns.Question{
|
||||
question("cachesize.bind."),
|
||||
question("insertions.bind."),
|
||||
question("evictions.bind."),
|
||||
question("misses.bind."),
|
||||
question("hits.bind."),
|
||||
question("auth.bind."),
|
||||
question("servers.bind."),
|
||||
},
|
||||
}
|
||||
in, _, err := s.dnsClient.Exchange(msg, s.dnsmasqAddr)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
for _, a := range in.Answer {
|
||||
txt, ok := a.(*dns.TXT)
|
||||
if !ok {
|
||||
continue
|
||||
}
|
||||
switch txt.Hdr.Name {
|
||||
case "servers.bind.":
|
||||
for _, str := range txt.Txt {
|
||||
arr := strings.Fields(str)
|
||||
if got, want := len(arr), 3; got != want {
|
||||
return fmt.Errorf("stats DNS record servers.bind.: unexpeced number of argument in record: got %d, want %d", got, want)
|
||||
}
|
||||
queries, err := strconv.ParseFloat(arr[1], 64)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
failedQueries, err := strconv.ParseFloat(arr[2], 64)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
serversMetrics["queries"].WithLabelValues(arr[0]).Set(queries)
|
||||
serversMetrics["queries_failed"].WithLabelValues(arr[0]).Set(failedQueries)
|
||||
}
|
||||
default:
|
||||
g, ok := floatMetrics[txt.Hdr.Name]
|
||||
if !ok {
|
||||
continue // ignore unexpected answer from dnsmasq
|
||||
}
|
||||
if got, want := len(txt.Txt), 1; got != want {
|
||||
return fmt.Errorf("stats DNS record %q: unexpected number of replies: got %d, want %d", txt.Hdr.Name, got, want)
|
||||
}
|
||||
f, err := strconv.ParseFloat(txt.Txt[0], 64)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
g.Set(f)
|
||||
}
|
||||
}
|
||||
return nil
|
||||
})
|
||||
|
||||
eg.Go(func() error {
|
||||
activeLeases, err := readLeaseFile(s.leasesPath)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
leases.Set(float64(len(activeLeases)))
|
||||
|
||||
if s.exposeLeases {
|
||||
for _, activeLease := range activeLeases {
|
||||
leaseMetrics.With(prometheus.Labels{
|
||||
"mac_addr": activeLease.macAddress,
|
||||
"ip_addr": activeLease.ipAddress,
|
||||
"computer_name": activeLease.computerName,
|
||||
"client_id": activeLease.clientId,
|
||||
}).Set(float64(activeLease.expiry))
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
})
|
||||
|
||||
if err := eg.Wait(); err != nil {
|
||||
http.Error(w, err.Error(), http.StatusInternalServerError)
|
||||
return
|
||||
}
|
||||
|
||||
s.promHandler.ServeHTTP(w, r)
|
||||
}
|
||||
|
||||
func main() {
|
||||
flag.Parse()
|
||||
s := &server{
|
||||
promHandler: promhttp.Handler(),
|
||||
dnsClient: &dns.Client{
|
||||
|
||||
var (
|
||||
dnsClient = &dns.Client{
|
||||
SingleInflight: true,
|
||||
},
|
||||
dnsmasqAddr: *dnsmasqAddr,
|
||||
leasesPath: *leasesPath,
|
||||
exposeLeases: *exposeLeases,
|
||||
}
|
||||
http.HandleFunc(*metricsPath, s.metrics)
|
||||
}
|
||||
cfg = collector.Config{
|
||||
DnsClient: dnsClient,
|
||||
DnsmasqAddr: *dnsmasqAddr,
|
||||
LeasesPath: *leasesPath,
|
||||
ExposeLeases: *exposeLeases,
|
||||
}
|
||||
collector = collector.New(cfg)
|
||||
reg = prometheus.NewRegistry()
|
||||
)
|
||||
|
||||
reg.MustRegister(collector)
|
||||
|
||||
http.Handle(*metricsPath, promhttp.HandlerFor(
|
||||
prometheus.Gatherers{prometheus.DefaultGatherer, reg},
|
||||
promhttp.HandlerOpts{},
|
||||
))
|
||||
http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
|
||||
w.Write([]byte(`<html>
|
||||
<head><title>Dnsmasq Exporter</title></head>
|
||||
|
|
@ -341,7 +82,6 @@ func main() {
|
|||
<p><a href="` + *metricsPath + `">Metrics</a></p>
|
||||
</body></html>`))
|
||||
})
|
||||
|
||||
log.Println("Listening on", *listen)
|
||||
log.Println("Service metrics under", *metricsPath)
|
||||
log.Fatal(http.ListenAndServe(*listen, nil))
|
||||
|
|
|
|||
Loading…
Reference in a new issue