Use the `ClusterPeer` interface from grafana/alerting (#61409)

* Use the Cluster interface from grafana/alerting

pkg/services/ngalert/notifier/alertmanager.go

@@ -18,7 +18,6 @@ import (
 	"github.com/grafana/alerting/alerting"
 	"github.com/grafana/alerting/alerting/notifier/channels"
 	amv2 "github.com/prometheus/alertmanager/api/v2/models"
-	"github.com/prometheus/alertmanager/cluster"
 	"github.com/prometheus/alertmanager/config"
 	"github.com/prometheus/alertmanager/dispatch"
 	"github.com/prometheus/alertmanager/inhibit"
@@ -31,7 +30,6 @@ import (
 	"github.com/prometheus/alertmanager/template"
 	"github.com/prometheus/alertmanager/timeinterval"
 	"github.com/prometheus/alertmanager/types"
-	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/common/model"
 
 	alertingModels "github.com/grafana/alerting/alerting/models"
@@ -82,12 +80,6 @@ func init() {
 	}
 }
 
-type ClusterPeer interface {
-	AddState(string, cluster.State, prometheus.Registerer) cluster.ClusterChannel
-	Position() int
-	WaitReady(context.Context) error
-}
-
 type AlertingStore interface {
 	store.AlertingStore
 	store.ImageStore
@@ -106,7 +98,7 @@ type Alertmanager struct {
 	marker          types.Marker
 	alerts          *mem.Alerts
 	route           *dispatch.Route
-	peer            ClusterPeer
+	peer            alerting.ClusterPeer
 	peerTimeout     time.Duration
 
 	dispatcher *dispatch.Dispatcher
@@ -163,7 +155,7 @@ func (m maintenanceOptions) MaintenanceFunc(state alerting.State) (int64, error)
 }
 
 func newAlertmanager(ctx context.Context, orgID int64, cfg *setting.Cfg, store AlertingStore, kvStore kvstore.KVStore,
-	peer ClusterPeer, decryptFn channels.GetDecryptedValueFn, ns notifications.Service, m *metrics.Alertmanager) (*Alertmanager, error) {
+	peer alerting.ClusterPeer, decryptFn channels.GetDecryptedValueFn, ns notifications.Service, m *metrics.Alertmanager) (*Alertmanager, error) {
 	am := &Alertmanager{
 		Settings:            cfg,
 		stopc:               make(chan struct{}),

pkg/services/ngalert/notifier/multiorg_alertmanager.go

@@ -9,10 +9,7 @@ import (
 	"sync"
 	"time"
 
-	"github.com/grafana/grafana/pkg/services/ngalert/provisioning"
-	"github.com/grafana/grafana/pkg/services/notifications"
-	"github.com/grafana/grafana/pkg/services/secrets"
-
+	"github.com/grafana/alerting/alerting"
 	"github.com/grafana/alerting/alerting/notifier/channels"
 	"github.com/prometheus/alertmanager/cluster"
 	"github.com/prometheus/client_golang/prometheus"
@@ -21,7 +18,10 @@ import (
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/services/ngalert/metrics"
 	"github.com/grafana/grafana/pkg/services/ngalert/models"
+	"github.com/grafana/grafana/pkg/services/ngalert/provisioning"
 	"github.com/grafana/grafana/pkg/services/ngalert/store"
+	"github.com/grafana/grafana/pkg/services/notifications"
+	"github.com/grafana/grafana/pkg/services/secrets"
 	"github.com/grafana/grafana/pkg/setting"
 )
 
@@ -41,7 +41,7 @@ type MultiOrgAlertmanager struct {
 	logger   log.Logger
 
 	// clusterPeer represents the clustering peers of Alertmanagers between Grafana instances.
-	peer         ClusterPeer
+	peer         alerting.ClusterPeer
 	settleCancel context.CancelFunc
 
 	configStore AlertingStore