alertmanager/inhibit.go

126 lines
3.1 KiB
Go

package main
import (
"sync"
"github.com/prometheus/common/log"
"github.com/prometheus/common/model"
"github.com/prometheus/alertmanager/config"
"github.com/prometheus/alertmanager/provider"
"github.com/prometheus/alertmanager/types"
)
type Inhibitor struct {
alerts provider.Alerts
rules []*InhibitRule
mtx sync.RWMutex
}
func NewInhibitor(ap provider.Alerts, rs []*config.InhibitRule) *Inhibitor {
ih := &Inhibitor{
alerts: ap,
}
for _, cr := range rs {
ih.rules = append(ih.rules, NewInhibitRule(cr))
}
return ih
}
func (ih *Inhibitor) Mutes(lset model.LabelSet) bool {
alerts := ih.alerts.GetPending()
defer alerts.Close()
// TODO(fabxc): improve erroring for iterators so it does not
// go silenced here.
for alert := range alerts.Next() {
if err := alerts.Err(); err != nil {
log.Errorf("Error iterating alerts: %s", err)
continue
}
if alert.Resolved() {
continue
}
for _, rule := range ih.rules {
if rule.Mutes(alert.Labels, lset) {
return true
}
}
}
return false
}
// An InhibitRule specifies that a class of (source) alerts should inhibit
// notifications for another class of (target) alerts if all specified matching
// labels are equal between the two alerts. This may be used to inhibit alerts
// from sending notifications if their meaning is logically a subset of a
// higher-level alert.
type InhibitRule struct {
// The set of Filters which define the group of source alerts (which inhibit
// the target alerts).
SourceMatchers types.Matchers
// The set of Filters which define the group of target alerts (which are
// inhibited by the source alerts).
TargetMatchers types.Matchers
// A set of label names whose label values need to be identical in source and
// target alerts in order for the inhibition to take effect.
Equal map[model.LabelName]struct{}
}
func NewInhibitRule(cr *config.InhibitRule) *InhibitRule {
var (
sourcem types.Matchers
targetm types.Matchers
)
for ln, lv := range cr.SourceMatch {
sourcem = append(sourcem, types.NewMatcher(model.LabelName(ln), lv))
}
for ln, lv := range cr.SourceMatchRE {
m, err := types.NewRegexMatcher(model.LabelName(ln), lv.String())
if err != nil {
// Must have been sanitized during config validation.
panic(err)
}
sourcem = append(sourcem, m)
}
for ln, lv := range cr.TargetMatch {
targetm = append(targetm, types.NewMatcher(model.LabelName(ln), lv))
}
for ln, lv := range cr.TargetMatchRE {
m, err := types.NewRegexMatcher(model.LabelName(ln), lv.String())
if err != nil {
// Must have been sanitized during config validation.
panic(err)
}
targetm = append(targetm, m)
}
equal := map[model.LabelName]struct{}{}
for _, ln := range cr.Equal {
equal[ln] = struct{}{}
}
return &InhibitRule{
SourceMatchers: sourcem,
TargetMatchers: targetm,
Equal: equal,
}
}
func (r *InhibitRule) Mutes(source, target model.LabelSet) bool {
if !r.TargetMatchers.Match(target) || !r.SourceMatchers.Match(source) {
return false
}
for ln := range r.Equal {
if source[ln] != target[ln] {
return false
}
}
return true
}