feat: add names to inhibit rules (#4628)

- add Name field to config.InhibitRule
- add Name field to inhibit.InhibitRule
- update docs for inhibit_rule

The name will be used in new metrics to be added in a separate change.

Signed-off-by: Siavash Safi <[email protected]>

Author: siavashs

config/config.go

@@ -955,6 +955,8 @@ func (r *Route) UnmarshalYAML(unmarshal func(any) error) error {
 // target labels if an alert matching the source labels exists.
 // Both alerts have to have a set of labels being equal.
 type InhibitRule struct {
+	// Name is an optional name for the inhibition rule.
+	Name string `yaml:"name,omitempty" json:"name,omitempty"`
 	// SourceMatch defines a set of labels that have to equal the given
 	// value for source alerts. Deprecated. Remove before v1.0 release.
 	SourceMatch map[string]string `yaml:"source_match,omitempty" json:"source_match,omitempty"`

docs/configuration.md

@@ -441,6 +441,9 @@ source matchers in a way that alerts never match both sides. It is much easier
 to reason about and does not trigger this special case.
 
 ```yaml
+# Optional name of the inhibition rule.
+name: <string>
+
 # DEPRECATED: Use target_matchers below.
 # Matchers that have to be fulfilled in the alerts to be muted.
 target_match:

inhibit/inhibit.go

@@ -153,6 +153,8 @@ func (ih *Inhibitor) Mutes(lset model.LabelSet) bool {
 // from sending notifications if their meaning is logically a subset of a
 // higher-level alert.
 type InhibitRule struct {
+	// Name is an optional name for the inhibition rule.
+	Name string
 	// The set of Filters which define the group of source alerts (which inhibit
 	// the target alerts).
 	SourceMatchers labels.Matchers
@@ -227,12 +229,14 @@ func NewInhibitRule(cr config.InhibitRule) *InhibitRule {
 	}
 
 	rule := &InhibitRule{
+		Name:           cr.Name,
 		SourceMatchers: sourcem,
 		TargetMatchers: targetm,
 		Equal:          equal,
 		scache:         store.NewAlerts(),
 		sindex:         newIndex(),
 	}
+
 	rule.scache.SetGCCallback(rule.gcCallback)
 
 	return rule

inhibit/inhibit_test.go

@@ -20,6 +20,7 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/model"
 	"github.com/prometheus/common/promslog"
+	"github.com/stretchr/testify/require"
 
 	"github.com/prometheus/alertmanager/config"
 	"github.com/prometheus/alertmanager/pkg/labels"
@@ -345,6 +346,36 @@ func TestInhibitRuleMatchers(t *testing.T) {
 	}
 }
 
+func TestInhibitRuleName(t *testing.T) {
+	t.Parallel()
+
+	config1 := config.InhibitRule{
+		Name: "test-rule",
+		SourceMatchers: []*labels.Matcher{
+			{Type: labels.MatchEqual, Name: "severity", Value: "critical"},
+		},
+		TargetMatchers: []*labels.Matcher{
+			{Type: labels.MatchEqual, Name: "severity", Value: "warning"},
+		},
+		Equal: []string{"instance"},
+	}
+	config2 := config.InhibitRule{
+		SourceMatchers: []*labels.Matcher{
+			{Type: labels.MatchEqual, Name: "severity", Value: "critical"},
+		},
+		TargetMatchers: []*labels.Matcher{
+			{Type: labels.MatchEqual, Name: "severity", Value: "warning"},
+		},
+		Equal: []string{"instance"},
+	}
+
+	rule1 := NewInhibitRule(config1)
+	rule2 := NewInhibitRule(config2)
+
+	require.Equal(t, "test-rule", rule1.Name, "Expected named rule to have adopt name from config")
+	require.Empty(t, rule2.Name, "Expected unnamed rule to have empty name")
+}
+
 type fakeAlerts struct {
 	alerts   []*types.Alert
 	finished chan struct{}