VictoriaMetrics/app/vmalert/main.go

446 lines
15 KiB
Go

package main
import (
"context"
"flag"
"fmt"
"net/url"
"os"
"strconv"
"strings"
"sync"
"time"
"github.com/VictoriaMetrics/metrics"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/config"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/datasource"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/notifier"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/remoteread"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/remotewrite"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/rule"
"github.com/VictoriaMetrics/VictoriaMetrics/app/vmalert/templates"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/buildinfo"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/envflag"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/fasttime"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/flagutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/httpserver"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/logger"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/procutil"
"github.com/VictoriaMetrics/VictoriaMetrics/lib/pushmetrics"
)
var (
rulePath = flagutil.NewArrayString("rule", `Path to the files or http url with alerting and/or recording rules.
Supports hierarchical patterns and regexpes.
Examples:
-rule="/path/to/file". Path to a single file with alerting rules.
-rule="http://<some-server-addr>/path/to/rules". HTTP URL to a page with alerting rules.
-rule="dir/*.yaml" -rule="/*.yaml" -rule="gcs://vmalert-rules/tenant_%{TENANT_ID}/prod".
-rule="dir/**/*.yaml". Includes all the .yaml files in "dir" subfolders recursively.
Rule files may contain %{ENV_VAR} placeholders, which are substituted by the corresponding env vars.
Enterprise version of vmalert supports S3 and GCS paths to rules.
For example: gs://bucket/path/to/rules, s3://bucket/path/to/rules
S3 and GCS paths support only matching by prefix, e.g. s3://bucket/dir/rule_ matches
all files with prefix rule_ in folder dir.
See https://docs.victoriametrics.com/vmalert/#reading-rules-from-object-storage
`)
ruleTemplatesPath = flagutil.NewArrayString("rule.templates", `Path or glob pattern to location with go template definitions `+
`for rules annotations templating. Flag can be specified multiple times.
Examples:
-rule.templates="/path/to/file". Path to a single file with go templates
-rule.templates="dir/*.tpl" -rule.templates="/*.tpl". Relative path to all .tpl files in "dir" folder,
absolute path to all .tpl files in root.
-rule.templates="dir/**/*.tpl". Includes all the .tpl files in "dir" subfolders recursively.
`)
configCheckInterval = flag.Duration("configCheckInterval", 0, "Interval for checking for changes in '-rule' or '-notifier.config' files. "+
"By default, the checking is disabled. Send SIGHUP signal in order to force config check for changes.")
httpListenAddrs = flagutil.NewArrayString("httpListenAddr", "Address to listen for incoming http requests. See also -tls and -httpListenAddr.useProxyProtocol")
useProxyProtocol = flagutil.NewArrayBool("httpListenAddr.useProxyProtocol", "Whether to use proxy protocol for connections accepted at the corresponding -httpListenAddr . "+
"See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt . "+
"With enabled proxy protocol http server cannot serve regular /metrics endpoint. Use -pushmetrics.url for metrics pushing")
evaluationInterval = flag.Duration("evaluationInterval", time.Minute, "How often to evaluate the rules")
validateTemplates = flag.Bool("rule.validateTemplates", true, "Whether to validate annotation and label templates")
validateExpressions = flag.Bool("rule.validateExpressions", true, "Whether to validate rules expressions via MetricsQL engine")
externalURL = flag.String("external.url", "", "External URL is used as alert's source for sent alerts to the notifier. By default, hostname is used as address.")
externalAlertSource = flag.String("external.alert.source", "", `External Alert Source allows to override the Source link for alerts sent to AlertManager `+
`for cases where you want to build a custom link to Grafana, Prometheus or any other service. `+
`Supports templating - see https://docs.victoriametrics.com/vmalert/#templating . `+
`For example, link to Grafana: -external.alert.source='explore?orgId=1&left={"datasource":"VictoriaMetrics","queries":[{"expr":{{$expr|jsonEscape|queryEscape}},"refId":"A"}],"range":{"from":"now-1h","to":"now"}}'. `+
`Link to VMUI: -external.alert.source='vmui/#/?g0.expr={{.Expr|queryEscape}}'. `+
`If empty 'vmalert/alert?group_id={{.GroupID}}&alert_id={{.AlertID}}' is used.`)
externalLabels = flagutil.NewArrayString("external.label", "Optional label in the form 'Name=value' to add to all generated recording rules and alerts. "+
"Pass multiple -label flags in order to add multiple label sets.")
remoteReadIgnoreRestoreErrors = flag.Bool("remoteRead.ignoreRestoreErrors", true, "Whether to ignore errors from remote storage when restoring alerts state on startup. DEPRECATED - this flag has no effect and will be removed in the next releases.")
dryRun = flag.Bool("dryRun", false, "Whether to check only config files without running vmalert. The rules file are validated. The -rule flag must be specified.")
)
var alertURLGeneratorFn notifier.AlertURLGenerator
func main() {
// Write flags and help message to stdout, since it is easier to grep or pipe.
flag.CommandLine.SetOutput(os.Stdout)
flag.Usage = usage
envflag.Parse()
remoteread.InitSecretFlags()
remotewrite.InitSecretFlags()
datasource.InitSecretFlags()
notifier.InitSecretFlags()
buildinfo.Init()
logger.Init()
if !*remoteReadIgnoreRestoreErrors {
logger.Warnf("flag `remoteRead.ignoreRestoreErrors` is deprecated and will be removed in next releases.")
}
err := templates.Load(*ruleTemplatesPath, true)
if err != nil {
logger.Fatalf("failed to parse %q: %s", *ruleTemplatesPath, err)
}
if *dryRun {
groups, err := config.Parse(*rulePath, notifier.ValidateTemplates, true)
if err != nil {
logger.Fatalf("failed to parse %q: %s", *rulePath, err)
}
if len(groups) == 0 {
logger.Fatalf("No rules for validation. Please specify path to file(s) with alerting and/or recording rules using `-rule` flag")
}
return
}
eu, err := getExternalURL(*externalURL)
if err != nil {
logger.Fatalf("failed to init `-external.url`: %s", err)
}
alertURLGeneratorFn, err = getAlertURLGenerator(eu, *externalAlertSource, *validateTemplates)
if err != nil {
logger.Fatalf("failed to init `external.alert.source`: %s", err)
}
var validateTplFn config.ValidateTplFn
if *validateTemplates {
validateTplFn = notifier.ValidateTemplates
}
if *replayFrom != "" || *replayTo != "" {
rw, err := remotewrite.Init(context.Background())
if err != nil {
logger.Fatalf("failed to init remoteWrite: %s", err)
}
if rw == nil {
logger.Fatalf("remoteWrite.url can't be empty in replay mode")
}
groupsCfg, err := config.Parse(*rulePath, validateTplFn, *validateExpressions)
if err != nil {
logger.Fatalf("cannot parse configuration file: %s", err)
}
// prevent queries from caching and boundaries aligning
// when querying VictoriaMetrics datasource.
q, err := datasource.Init(url.Values{"nocache": {"1"}})
if err != nil {
logger.Fatalf("failed to init datasource: %s", err)
}
if err := replay(groupsCfg, q, rw); err != nil {
logger.Fatalf("replay failed: %s", err)
}
return
}
ctx, cancel := context.WithCancel(context.Background())
manager, err := newManager(ctx)
if err != nil {
logger.Fatalf("failed to init: %s", err)
}
logger.Infof("reading rules configuration file from %q", strings.Join(*rulePath, ";"))
groupsCfg, err := config.Parse(*rulePath, validateTplFn, *validateExpressions)
if err != nil {
logger.Fatalf("cannot parse configuration file: %s", err)
}
// Register SIGHUP handler for config re-read just before manager.start call.
// This guarantees that the config will be re-read if the signal arrives during manager.start call.
// See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1240
sighupCh := procutil.NewSighupChan()
if err := manager.start(ctx, groupsCfg); err != nil {
logger.Fatalf("failed to start: %s", err)
}
go configReload(ctx, manager, groupsCfg, sighupCh)
listenAddrs := *httpListenAddrs
if len(listenAddrs) == 0 {
listenAddrs = []string{":8880"}
}
rh := &requestHandler{m: manager}
go httpserver.Serve(listenAddrs, useProxyProtocol, rh.handler)
pushmetrics.Init()
sig := procutil.WaitForSigterm()
logger.Infof("service received signal %s", sig)
pushmetrics.Stop()
if err := httpserver.Stop(listenAddrs); err != nil {
logger.Fatalf("cannot stop the webservice: %s", err)
}
cancel()
manager.close()
}
var (
configReloads = metrics.NewCounter(`vmalert_config_last_reload_total`)
configReloadErrors = metrics.NewCounter(`vmalert_config_last_reload_errors_total`)
configSuccess = metrics.NewGauge(`vmalert_config_last_reload_successful`, nil)
configTimestamp = metrics.NewCounter(`vmalert_config_last_reload_success_timestamp_seconds`)
)
func newManager(ctx context.Context) (*manager, error) {
q, err := datasource.Init(nil)
if err != nil {
return nil, fmt.Errorf("failed to init datasource: %w", err)
}
labels := make(map[string]string)
for _, s := range *externalLabels {
if len(s) == 0 {
continue
}
n := strings.IndexByte(s, '=')
if n < 0 {
return nil, fmt.Errorf("missing '=' in `-label`. It must contain label in the form `Name=value`; got %q", s)
}
labels[s[:n]] = s[n+1:]
}
nts, err := notifier.Init(alertURLGeneratorFn, labels, *externalURL)
if err != nil {
return nil, fmt.Errorf("failed to init notifier: %w", err)
}
manager := &manager{
groups: make(map[uint64]*rule.Group),
querierBuilder: q,
notifiers: nts,
labels: labels,
}
rw, err := remotewrite.Init(ctx)
if err != nil {
return nil, fmt.Errorf("failed to init remoteWrite: %w", err)
}
if rw != nil {
manager.rw = rw
}
rr, err := remoteread.Init()
if err != nil {
return nil, fmt.Errorf("failed to init remoteRead: %w", err)
}
manager.rr = rr
return manager, nil
}
func getExternalURL(customURL string) (*url.URL, error) {
if customURL == "" {
// use local hostname as external URL
listenAddr := ":8880"
if len(*httpListenAddrs) > 0 {
listenAddr = (*httpListenAddrs)[0]
}
isTLS := httpserver.IsTLS(0)
return getHostnameAsExternalURL(listenAddr, isTLS)
}
u, err := url.Parse(customURL)
if err != nil {
return nil, err
}
if u.Scheme != "http" && u.Scheme != "https" {
return nil, fmt.Errorf("invalid scheme %q in url %q, only 'http' and 'https' are supported", u.Scheme, u.String())
}
return u, nil
}
func getHostnameAsExternalURL(addr string, isSecure bool) (*url.URL, error) {
hname, err := os.Hostname()
if err != nil {
return nil, fmt.Errorf("failed to get hostname: %w", err)
}
port := ""
if ipport := strings.Split(addr, ":"); len(ipport) > 1 {
port = ":" + ipport[1]
}
schema := "http://"
if isSecure {
schema = "https://"
}
return url.Parse(fmt.Sprintf("%s%s%s", schema, hname, port))
}
func getAlertURLGenerator(externalURL *url.URL, externalAlertSource string, validateTemplate bool) (notifier.AlertURLGenerator, error) {
if externalAlertSource == "" {
return func(a notifier.Alert) string {
gID, aID := strconv.FormatUint(a.GroupID, 10), strconv.FormatUint(a.ID, 10)
return fmt.Sprintf("%s/vmalert/alert?%s=%s&%s=%s", externalURL, paramGroupID, gID, paramAlertID, aID)
}, nil
}
if validateTemplate {
if err := notifier.ValidateTemplates(map[string]string{
"tpl": externalAlertSource,
}); err != nil {
return nil, fmt.Errorf("error validating source template %s: %w", externalAlertSource, err)
}
}
m := map[string]string{
"tpl": externalAlertSource,
}
return func(alert notifier.Alert) string {
qFn := func(_ string) ([]datasource.Metric, error) {
return nil, fmt.Errorf("`query` template isn't supported for alert source template")
}
templated, err := alert.ExecTemplate(qFn, alert.Labels, m)
if err != nil {
logger.Errorf("can not exec source template %s", err)
}
return fmt.Sprintf("%s/%s", externalURL, templated["tpl"])
}, nil
}
func usage() {
const s = `
vmalert processes alerts and recording rules.
See the docs at https://docs.victoriametrics.com/vmalert/ .
`
flagutil.Usage(s)
}
func configReload(ctx context.Context, m *manager, groupsCfg []config.Group, sighupCh <-chan os.Signal) {
var configCheckCh <-chan time.Time
checkInterval := *configCheckInterval
if checkInterval > 0 {
ticker := time.NewTicker(checkInterval)
configCheckCh = ticker.C
defer ticker.Stop()
}
var validateTplFn config.ValidateTplFn
if *validateTemplates {
validateTplFn = notifier.ValidateTemplates
}
// init metrics for config state with positive values to improve alerting conditions
setConfigSuccessAt(fasttime.UnixTimestamp())
parseFn := config.Parse
for {
select {
case <-ctx.Done():
return
case <-sighupCh:
tmplMsg := ""
if len(*ruleTemplatesPath) > 0 {
tmplMsg = fmt.Sprintf("and templates %q ", *ruleTemplatesPath)
}
logger.Infof("SIGHUP received. Going to reload rules %q %s...", *rulePath, tmplMsg)
configReloads.Inc()
// allow logs emitting during manual config reload
parseFn = config.Parse
case <-configCheckCh:
// disable logs emitting during per-interval config reload
parseFn = config.ParseSilent
}
if err := notifier.Reload(); err != nil {
setConfigError(err)
logger.Errorf("failed to reload notifier config: %s", err)
continue
}
err := templates.Load(*ruleTemplatesPath, false)
if err != nil {
setConfigError(err)
logger.Errorf("failed to load new templates: %s", err)
continue
}
newGroupsCfg, err := parseFn(*rulePath, validateTplFn, *validateExpressions)
if err != nil {
setConfigError(err)
logger.Errorf("cannot parse configuration file: %s", err)
continue
}
if configsEqual(newGroupsCfg, groupsCfg) {
templates.Reload()
// set success to 1 since previous reload could have been unsuccessful
// do not update configTimestamp as config version remains old.
configSuccess.Set(1)
// reset the last config error since the config change was rolled back
setLastConfigErr(nil)
// config didn't change - skip iteration
continue
}
if err := m.update(ctx, newGroupsCfg, false); err != nil {
setConfigError(err)
logger.Errorf("error while reloading rules: %s", err)
continue
}
templates.Reload()
groupsCfg = newGroupsCfg
setConfigSuccessAt(fasttime.UnixTimestamp())
logger.Infof("Rules reloaded successfully from %q", *rulePath)
}
}
func configsEqual(a, b []config.Group) bool {
if len(a) != len(b) {
return false
}
for i := range a {
if a[i].Checksum != b[i].Checksum {
return false
}
}
return true
}
// setConfigSuccessAt updates config related metrics as successful.
func setConfigSuccessAt(at uint64) {
configSuccess.Set(1)
configTimestamp.Set(at)
// reset the lastConfigErr
setLastConfigErr(nil)
}
// setConfigError updates config related metrics according to the error.
func setConfigError(err error) {
configReloadErrors.Inc()
configSuccess.Set(0)
setLastConfigErr(err)
}
var (
lastConfigErrMu sync.RWMutex
// lastConfigErr represent the error message from the last config reload.
// The message is used in web UI as notification
lastConfigErr error
)
func setLastConfigErr(err error) {
lastConfigErrMu.Lock()
lastConfigErr = err
lastConfigErrMu.Unlock()
}
func getLastConfigError() error {
lastConfigErrMu.RLock()
defer lastConfigErrMu.RUnlock()
return lastConfigErr
}