VictoriaMetrics/lib/promscrape/scraper.go
Nikolay Khramchikhin b4c77fc6d2 Adds openstack sd (#811)
* adds openstack service discovery

https://github.com/VictoriaMetrics/VictoriaMetrics/issues/728

 implemented hypervisors and instance discovery with openstack v3 api.
 Added tests for labeling and data parsing.
 Added token refresh.

* Apply suggestions from code review

* Apply suggestions from code review

Co-authored-by: Aliaksandr Valialkin <valyala@gmail.com>
2020-10-05 16:48:54 +03:00

328 lines
11 KiB
Go

package promscrape
import (
"bytes"
"flag"
"fmt"
"sync"
"time"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/procutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/prompbmarshal"
"github.com/VictoriaMetrics/metrics"
)
var (
configCheckInterval = flag.Duration("promscrape.configCheckInterval", 0, "Interval for checking for changes in '-promscrape.config' file. "+
"By default the checking is disabled. Send SIGHUP signal in order to force config check for changes")
fileSDCheckInterval = flag.Duration("promscrape.fileSDCheckInterval", 30*time.Second, "Interval for checking for changes in 'file_sd_config'. "+
"See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#file_sd_config for details")
kubernetesSDCheckInterval = flag.Duration("promscrape.kubernetesSDCheckInterval", 30*time.Second, "Interval for checking for changes in Kubernetes API server. "+
"This works only if `kubernetes_sd_configs` is configured in '-promscrape.config' file. "+
"See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#kubernetes_sd_config for details")
openstackSDCheckInterval = flag.Duration("promscrape.openstackSDCheckInterval", 30*time.Second, "Interval for checking for changes in openstack API server. "+
"This works only if `openstack_sd_configs` is configured in '-promscrape.config' file. "+
"See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#openstack_sd_config for details")
consulSDCheckInterval = flag.Duration("promscrape.consulSDCheckInterval", 30*time.Second, "Interval for checking for changes in consul. "+
"This works only if `consul_sd_configs` is configured in '-promscrape.config' file. "+
"See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#consul_sd_config for details")
dnsSDCheckInterval = flag.Duration("promscrape.dnsSDCheckInterval", 30*time.Second, "Interval for checking for changes in dns. "+
"This works only if `dns_sd_configs` is configured in '-promscrape.config' file. "+
"See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#dns_sd_config for details")
ec2SDCheckInterval = flag.Duration("promscrape.ec2SDCheckInterval", time.Minute, "Interval for checking for changes in ec2. "+
"This works only if `ec2_sd_configs` is configured in '-promscrape.config' file. "+
"See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#ec2_sd_config for details")
gceSDCheckInterval = flag.Duration("promscrape.gceSDCheckInterval", time.Minute, "Interval for checking for changes in gce. "+
"This works only if `gce_sd_configs` is configured in '-promscrape.config' file. "+
"See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#gce_sd_config for details")
promscrapeConfigFile = flag.String("promscrape.config", "", "Optional path to Prometheus config file with 'scrape_configs' section containing targets to scrape. "+
"See https://victoriametrics.github.io/#how-to-scrape-prometheus-exporters-such-as-node-exporter for details")
)
// CheckConfig checks -promscrape.config for errors and unsupported options.
func CheckConfig() error {
if *promscrapeConfigFile == "" {
return fmt.Errorf("missing -promscrape.config option")
}
_, _, err := loadConfig(*promscrapeConfigFile)
return err
}
// Init initializes Prometheus scraper with config from the `-promscrape.config`.
//
// Scraped data is passed to pushData.
func Init(pushData func(wr *prompbmarshal.WriteRequest)) {
globalStopCh = make(chan struct{})
scraperWG.Add(1)
go func() {
defer scraperWG.Done()
runScraper(*promscrapeConfigFile, pushData, globalStopCh)
}()
}
// Stop stops Prometheus scraper.
func Stop() {
close(globalStopCh)
scraperWG.Wait()
}
var (
globalStopCh chan struct{}
scraperWG sync.WaitGroup
)
func runScraper(configFile string, pushData func(wr *prompbmarshal.WriteRequest), globalStopCh <-chan struct{}) {
if configFile == "" {
// Nothing to scrape.
return
}
logger.Infof("reading Prometheus configs from %q", configFile)
cfg, data, err := loadConfig(configFile)
if err != nil {
logger.Fatalf("cannot read %q: %s", configFile, err)
}
scs := newScrapeConfigs(pushData)
scs.add("static_configs", 0, func(cfg *Config, swsPrev []ScrapeWork) []ScrapeWork { return cfg.getStaticScrapeWork() })
scs.add("file_sd_configs", *fileSDCheckInterval, func(cfg *Config, swsPrev []ScrapeWork) []ScrapeWork { return cfg.getFileSDScrapeWork(swsPrev) })
scs.add("kubernetes_sd_configs", *kubernetesSDCheckInterval, func(cfg *Config, swsPrev []ScrapeWork) []ScrapeWork { return cfg.getKubernetesSDScrapeWork(swsPrev) })
scs.add("openstack_sd_configs", *openstackSDCheckInterval, func(cfg *Config, swsPrev []ScrapeWork) []ScrapeWork { return cfg.getOpenStackSDScrapeWork(swsPrev) })
scs.add("consul_sd_configs", *consulSDCheckInterval, func(cfg *Config, swsPrev []ScrapeWork) []ScrapeWork { return cfg.getConsulSDScrapeWork(swsPrev) })
scs.add("dns_sd_configs", *dnsSDCheckInterval, func(cfg *Config, swsPrev []ScrapeWork) []ScrapeWork { return cfg.getDNSSDScrapeWork(swsPrev) })
scs.add("ec2_sd_configs", *ec2SDCheckInterval, func(cfg *Config, swsPrev []ScrapeWork) []ScrapeWork { return cfg.getEC2SDScrapeWork(swsPrev) })
scs.add("gce_sd_configs", *gceSDCheckInterval, func(cfg *Config, swsPrev []ScrapeWork) []ScrapeWork { return cfg.getGCESDScrapeWork(swsPrev) })
sighupCh := procutil.NewSighupChan()
var tickerCh <-chan time.Time
if *configCheckInterval > 0 {
ticker := time.NewTicker(*configCheckInterval)
tickerCh = ticker.C
defer ticker.Stop()
}
for {
scs.updateConfig(cfg)
waitForChans:
select {
case <-sighupCh:
logger.Infof("SIGHUP received; reloading Prometheus configs from %q", configFile)
cfgNew, dataNew, err := loadConfig(configFile)
if err != nil {
logger.Errorf("cannot read %q on SIGHUP: %s; continuing with the previous config", configFile, err)
goto waitForChans
}
if bytes.Equal(data, dataNew) {
logger.Infof("nothing changed in %q", configFile)
goto waitForChans
}
cfg = cfgNew
data = dataNew
case <-tickerCh:
cfgNew, dataNew, err := loadConfig(configFile)
if err != nil {
logger.Errorf("cannot read %q: %s; continuing with the previous config", configFile, err)
goto waitForChans
}
if bytes.Equal(data, dataNew) {
// Nothing changed since the previous loadConfig
goto waitForChans
}
cfg = cfgNew
data = dataNew
case <-globalStopCh:
logger.Infof("stopping Prometheus scrapers")
startTime := time.Now()
scs.stop()
logger.Infof("stopped Prometheus scrapers in %.3f seconds", time.Since(startTime).Seconds())
return
}
logger.Infof("found changes in %q; applying these changes", configFile)
configReloads.Inc()
}
}
var configReloads = metrics.NewCounter(`vm_promscrape_config_reloads_total`)
type scrapeConfigs struct {
pushData func(wr *prompbmarshal.WriteRequest)
wg sync.WaitGroup
stopCh chan struct{}
scfgs []*scrapeConfig
}
func newScrapeConfigs(pushData func(wr *prompbmarshal.WriteRequest)) *scrapeConfigs {
return &scrapeConfigs{
pushData: pushData,
stopCh: make(chan struct{}),
}
}
func (scs *scrapeConfigs) add(name string, checkInterval time.Duration, getScrapeWork func(cfg *Config, swsPrev []ScrapeWork) []ScrapeWork) {
scfg := &scrapeConfig{
name: name,
pushData: scs.pushData,
getScrapeWork: getScrapeWork,
checkInterval: checkInterval,
cfgCh: make(chan *Config, 1),
stopCh: scs.stopCh,
}
scs.wg.Add(1)
go func() {
defer scs.wg.Done()
scfg.run()
}()
scs.scfgs = append(scs.scfgs, scfg)
}
func (scs *scrapeConfigs) updateConfig(cfg *Config) {
for _, scfg := range scs.scfgs {
scfg.cfgCh <- cfg
}
}
func (scs *scrapeConfigs) stop() {
close(scs.stopCh)
scs.wg.Wait()
scs.scfgs = nil
}
type scrapeConfig struct {
name string
pushData func(wr *prompbmarshal.WriteRequest)
getScrapeWork func(cfg *Config, swsPrev []ScrapeWork) []ScrapeWork
checkInterval time.Duration
cfgCh chan *Config
stopCh <-chan struct{}
}
func (scfg *scrapeConfig) run() {
sg := newScraperGroup(scfg.name, scfg.pushData)
defer sg.stop()
var tickerCh <-chan time.Time
if scfg.checkInterval > 0 {
ticker := time.NewTicker(scfg.checkInterval)
defer ticker.Stop()
tickerCh = ticker.C
}
cfg := <-scfg.cfgCh
var swsPrev []ScrapeWork
for {
sws := scfg.getScrapeWork(cfg, swsPrev)
sg.update(sws)
swsPrev = sws
select {
case <-scfg.stopCh:
return
case cfg = <-scfg.cfgCh:
case <-tickerCh:
}
}
}
type scraperGroup struct {
name string
wg sync.WaitGroup
mLock sync.Mutex
m map[string]*scraper
pushData func(wr *prompbmarshal.WriteRequest)
changesCount *metrics.Counter
}
func newScraperGroup(name string, pushData func(wr *prompbmarshal.WriteRequest)) *scraperGroup {
sg := &scraperGroup{
name: name,
m: make(map[string]*scraper),
pushData: pushData,
changesCount: metrics.NewCounter(fmt.Sprintf(`vm_promscrape_config_changes_total{type=%q}`, name)),
}
metrics.NewGauge(fmt.Sprintf(`vm_promscrape_targets{type=%q, status="up"}`, name), func() float64 {
return float64(tsmGlobal.StatusByGroup(sg.name, true))
})
metrics.NewGauge(fmt.Sprintf(`vm_promscrape_targets{type=%q, status="down"}`, name), func() float64 {
return float64(tsmGlobal.StatusByGroup(sg.name, false))
})
return sg
}
func (sg *scraperGroup) stop() {
sg.mLock.Lock()
for _, sc := range sg.m {
close(sc.stopCh)
}
sg.m = nil
sg.mLock.Unlock()
sg.wg.Wait()
}
func (sg *scraperGroup) update(sws []ScrapeWork) {
sg.mLock.Lock()
defer sg.mLock.Unlock()
additionsCount := 0
deletionsCount := 0
swsMap := make(map[string]bool, len(sws))
for i := range sws {
sw := &sws[i]
key := sw.key()
if swsMap[key] {
logger.Errorf("skipping duplicate scrape target with identical labels; endpoint=%s, labels=%s; "+
"make sure service discovery and relabeling is set up properly; "+
"see also https://victoriametrics.github.io/vmagent.html#troubleshooting",
sw.ScrapeURL, sw.LabelsString())
continue
}
swsMap[key] = true
if sg.m[key] != nil {
// The scraper for the given key already exists.
continue
}
// Start a scraper for the missing key.
sc := newScraper(sw, sg.name, sg.pushData)
sg.wg.Add(1)
go func() {
defer sg.wg.Done()
sc.sw.run(sc.stopCh)
tsmGlobal.Unregister(sw)
}()
tsmGlobal.Register(sw)
sg.m[key] = sc
additionsCount++
}
// Stop deleted scrapers, which are missing in sws.
for key, sc := range sg.m {
if !swsMap[key] {
close(sc.stopCh)
delete(sg.m, key)
deletionsCount++
}
}
if additionsCount > 0 || deletionsCount > 0 {
sg.changesCount.Add(additionsCount + deletionsCount)
logger.Infof("%s: added targets: %d, removed targets: %d; total targets: %d", sg.name, additionsCount, deletionsCount, len(sg.m))
}
}
type scraper struct {
sw scrapeWork
stopCh chan struct{}
}
func newScraper(sw *ScrapeWork, group string, pushData func(wr *prompbmarshal.WriteRequest)) *scraper {
sc := &scraper{
stopCh: make(chan struct{}),
}
c := newClient(sw)
sc.sw.Config = *sw
sc.sw.ScrapeGroup = group
sc.sw.ReadData = c.ReadData
sc.sw.PushData = pushData
return sc
}