prometheus/main.go
Bjoern Rabenstein b3ed9aa7a2 Clean up start-up and shut-down.
Change-Id: Idff4bbb0a15a9f879bfbb3da5b1025179cab5e2c
2014-11-25 17:08:45 +01:00

270 lines
8.6 KiB
Go

// Copyright 2013 Prometheus Team
// 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 main
import (
"flag"
"os"
"os/signal"
"sync"
"syscall"
"time"
"github.com/golang/glog"
"github.com/prometheus/client_golang/extraction"
clientmodel "github.com/prometheus/client_golang/model"
registry "github.com/prometheus/client_golang/prometheus"
"github.com/prometheus/prometheus/config"
"github.com/prometheus/prometheus/notification"
"github.com/prometheus/prometheus/retrieval"
"github.com/prometheus/prometheus/rules/manager"
"github.com/prometheus/prometheus/storage/local"
"github.com/prometheus/prometheus/storage/remote"
"github.com/prometheus/prometheus/storage/remote/opentsdb"
"github.com/prometheus/prometheus/web"
"github.com/prometheus/prometheus/web/api"
)
const deletionBatchSize = 100
// Commandline flags.
var (
configFile = flag.String("configFile", "prometheus.conf", "Prometheus configuration file name.")
metricsStoragePath = flag.String("metricsStoragePath", "/tmp/metrics", "Base path for metrics storage.")
alertmanagerUrl = flag.String("alertmanager.url", "", "The URL of the alert manager to send notifications to.")
remoteTSDBUrl = flag.String("storage.remote.url", "", "The URL of the OpenTSDB instance to send samples to.")
remoteTSDBTimeout = flag.Duration("storage.remote.timeout", 30*time.Second, "The timeout to use when sending samples to OpenTSDB.")
samplesQueueCapacity = flag.Int("storage.queue.samplesCapacity", 4096, "The size of the unwritten samples queue.")
diskAppendQueueCapacity = flag.Int("storage.queue.diskAppendCapacity", 1000000, "The size of the queue for items that are pending writing to disk.")
memoryAppendQueueCapacity = flag.Int("storage.queue.memoryAppendCapacity", 10000, "The size of the queue for items that are pending writing to memory.")
memoryEvictionInterval = flag.Duration("storage.memory.evictionInterval", 15*time.Minute, "The period at which old data is evicted from memory.")
memoryRetentionPeriod = flag.Duration("storage.memory.retentionPeriod", time.Hour, "The period of time to retain in memory during evictions.")
storagePurgeInterval = flag.Duration("storage.purgeInterval", time.Hour, "How frequently to purge old data from the storage.")
storageRetentionPeriod = flag.Duration("storage.retentionPeriod", 15*24*time.Hour, "The period of time to retain in storage.")
notificationQueueCapacity = flag.Int("alertmanager.notificationQueueCapacity", 100, "The size of the queue for pending alert manager notifications.")
printVersion = flag.Bool("version", false, "print version information")
)
type prometheus struct {
unwrittenSamples chan *extraction.Result
ruleManager manager.RuleManager
targetManager retrieval.TargetManager
notificationHandler *notification.NotificationHandler
storage local.Storage
remoteTSDBQueue *remote.TSDBQueueManager
webService *web.WebService
closeOnce sync.Once
}
// NewPrometheus creates a new prometheus object based on flag values.
// Call Serve() to start serving and Close() for clean shutdown.
func NewPrometheus() *prometheus {
conf, err := config.LoadFromFile(*configFile)
if err != nil {
glog.Fatalf("Error loading configuration from %s: %v", *configFile, err)
}
unwrittenSamples := make(chan *extraction.Result, *samplesQueueCapacity)
ingester := &retrieval.MergeLabelsIngester{
Labels: conf.GlobalLabels(),
CollisionPrefix: clientmodel.ExporterLabelPrefix,
Ingester: retrieval.ChannelIngester(unwrittenSamples),
}
targetManager := retrieval.NewTargetManager(ingester)
targetManager.AddTargetsFromConfig(conf)
notificationHandler := notification.NewNotificationHandler(*alertmanagerUrl, *notificationQueueCapacity)
registry.MustRegister(notificationHandler)
o := &local.MemorySeriesStorageOptions{
MemoryEvictionInterval: *memoryEvictionInterval,
MemoryRetentionPeriod: *memoryRetentionPeriod,
PersistenceStoragePath: *metricsStoragePath,
PersistencePurgeInterval: *storagePurgeInterval,
PersistenceRetentionPeriod: *storageRetentionPeriod,
}
memStorage, err := local.NewMemorySeriesStorage(o)
if err != nil {
glog.Fatal("Error opening memory series storage: ", err)
}
registry.MustRegister(memStorage)
ruleManager := manager.NewRuleManager(&manager.RuleManagerOptions{
Results: unwrittenSamples,
NotificationHandler: notificationHandler,
EvaluationInterval: conf.EvaluationInterval(),
Storage: memStorage,
PrometheusUrl: web.MustBuildServerUrl(),
})
if err := ruleManager.AddRulesFromConfig(conf); err != nil {
glog.Fatal("Error loading rule files: ", err)
}
var remoteTSDBQueue *remote.TSDBQueueManager
if *remoteTSDBUrl == "" {
glog.Warningf("No TSDB URL provided; not sending any samples to long-term storage")
} else {
openTSDB := opentsdb.NewClient(*remoteTSDBUrl, *remoteTSDBTimeout)
remoteTSDBQueue = remote.NewTSDBQueueManager(openTSDB, 512)
registry.MustRegister(remoteTSDBQueue)
}
flags := map[string]string{}
flag.VisitAll(func(f *flag.Flag) {
flags[f.Name] = f.Value.String()
})
prometheusStatus := &web.PrometheusStatusHandler{
BuildInfo: BuildInfo,
Config: conf.String(),
RuleManager: ruleManager,
TargetPools: targetManager.Pools(),
Flags: flags,
Birth: time.Now(),
}
alertsHandler := &web.AlertsHandler{
RuleManager: ruleManager,
}
consolesHandler := &web.ConsolesHandler{
Storage: memStorage,
}
metricsService := &api.MetricsService{
Config: &conf,
TargetManager: targetManager,
Storage: memStorage,
}
webService := &web.WebService{
StatusHandler: prometheusStatus,
MetricsHandler: metricsService,
ConsolesHandler: consolesHandler,
AlertsHandler: alertsHandler,
}
p := &prometheus{
unwrittenSamples: unwrittenSamples,
ruleManager: ruleManager,
targetManager: targetManager,
notificationHandler: notificationHandler,
storage: memStorage,
remoteTSDBQueue: remoteTSDBQueue,
webService: webService,
}
webService.QuitDelegate = p.Close
return p
}
// Serve starts the Prometheus server. It returns after the server has been shut
// down. The method installs an interrupt handler, allowing to trigger a
// shutdown by sending SIGTERM to the process.
func (p *prometheus) Serve() {
if p.remoteTSDBQueue != nil {
go p.remoteTSDBQueue.Run()
}
go p.ruleManager.Run()
go p.notificationHandler.Run()
go p.interruptHandler()
storageStarted := make(chan struct{})
go p.storage.Serve(storageStarted)
<-storageStarted
go func() {
err := p.webService.ServeForever()
if err != nil {
glog.Fatal(err)
}
}()
for block := range p.unwrittenSamples {
if block.Err == nil && len(block.Samples) > 0 {
p.storage.AppendSamples(block.Samples)
if p.remoteTSDBQueue != nil {
p.remoteTSDBQueue.Queue(block.Samples)
}
}
}
// The following shut-down operations have to happen after
// unwrittenSamples is drained. So do not move them into close().
if err := p.storage.Close(); err != nil {
glog.Error("Error closing local storage: ", err)
}
glog.Info("Local Storage: Done")
if p.remoteTSDBQueue != nil {
p.remoteTSDBQueue.Stop()
glog.Info("Remote Storage: Done")
}
p.notificationHandler.Stop()
glog.Info("Sundry Queues: Done")
glog.Info("See you next time!")
}
// Close cleanly shuts down the Prometheus server.
func (p *prometheus) Close() {
p.closeOnce.Do(p.close)
}
func (p *prometheus) interruptHandler() {
notifier := make(chan os.Signal)
signal.Notify(notifier, os.Interrupt, syscall.SIGTERM)
<-notifier
glog.Warning("Received SIGTERM, exiting gracefully...")
p.Close()
}
func (p *prometheus) close() {
glog.Info("Shutdown has been requested; subsytems are closing:")
p.targetManager.Stop()
glog.Info("Remote Target Manager: Done")
p.ruleManager.Stop()
glog.Info("Rule Executor: Done")
close(p.unwrittenSamples)
// Note: Before closing the remaining subsystems (storage, ...), we have
// to wait until p.unwrittenSamples is actually drained. Therefore,
// remaining shut-downs happen in Serve().
}
func main() {
flag.Parse()
versionInfoTmpl.Execute(os.Stdout, BuildInfo)
if *printVersion {
os.Exit(0)
}
NewPrometheus().Serve()
}