Alerting: Limit and clean up old alert rules versions (#89754)

pkg/setting/setting_unified_alerting.go

@@ -121,6 +121,11 @@ type UnifiedAlertingSettings struct {
 
 	// Duration for which a resolved alert state transition will continue to be sent to the Alertmanager.
 	ResolvedAlertRetention time.Duration
+
+	// RuleVersionRecordLimit defines the limit of how many alert rule versions
+	// should be stored in the database for each alert_rule in an organization including the current one.
+	// 0 value means no limit
+	RuleVersionRecordLimit int
 }
 
 type RecordingRuleSettings struct {
@@ -455,6 +460,11 @@ func (cfg *Cfg) ReadUnifiedAlertingSettings(iniFile *ini.File) error {
 		return err
 	}
 
+	uaCfg.RuleVersionRecordLimit = ua.Key("rule_version_record_limit").MustInt(0)
+	if uaCfg.RuleVersionRecordLimit < 0 {
+		return fmt.Errorf("setting 'rule_version_record_limit' is invalid, only 0 or a positive integer are allowed")
+	}
+
 	cfg.UnifiedAlerting = uaCfg
 	return nil
 }