Alerting: Pass metrics Registerer into NewExternalAlertmanagerSender. (#88313)

* Alerting: Pass metrics Registerer into NewExternalAlertmanagerSender.

I will work on a separate change to export the metrics from Grafana, this
is a little more complicated.

* Typo

pkg/services/ngalert/remote/alertmanager.go

@@ -17,6 +17,7 @@ import (
 	amgeneral "github.com/prometheus/alertmanager/api/v2/client/general"
 	amreceiver "github.com/prometheus/alertmanager/api/v2/client/receiver"
 	amsilence "github.com/prometheus/alertmanager/api/v2/client/silence"
+	"github.com/prometheus/client_golang/prometheus"
 
 	alertingClusterPB "github.com/grafana/alerting/cluster/clusterpb"
 	alertingNotify "github.com/grafana/alerting/notify"
@@ -123,7 +124,7 @@ func NewAlertmanager(cfg AlertmanagerConfig, store stateStore, decryptFn Decrypt
 		return c.Do(req.WithContext(ctx))
 	}
 	senderLogger := log.New("ngalert.sender.external-alertmanager")
-	s := sender.NewExternalAlertmanagerSender(senderLogger, sender.WithDoFunc(doFunc))
+	s := sender.NewExternalAlertmanagerSender(senderLogger, prometheus.NewRegistry(), sender.WithDoFunc(doFunc))
 	s.Run()
 	err = s.ApplyConfig(cfg.OrgID, 0, []sender.ExternalAMcfg{{URL: cfg.URL + "/alertmanager"}})
 	if err != nil {

pkg/services/ngalert/sender/router.go

@@ -12,6 +12,7 @@ import (
 	"time"
 
 	"github.com/benbjohnson/clock"
+	"github.com/prometheus/client_golang/prometheus"
 
 	"github.com/grafana/grafana/pkg/api/datasource"
 	"github.com/grafana/grafana/pkg/infra/log"
@@ -164,7 +165,7 @@ func (d *AlertsRouter) SyncAndApplyConfigFromDatabase(ctx context.Context) error
 		// No sender and have Alertmanager(s) to send to - start a new one.
 		d.logger.Info("Creating new sender for the external alertmanagers", "org", cfg.OrgID, "alertmanagers", redactedAMs)
 		senderLogger := log.New("ngalert.sender.external-alertmanager")
-		s := NewExternalAlertmanagerSender(senderLogger)
+		s := NewExternalAlertmanagerSender(senderLogger, prometheus.NewRegistry())
 		d.externalAlertmanagers[cfg.OrgID] = s
 		s.Run()
 

pkg/services/ngalert/sender/sender.go

@@ -80,7 +80,7 @@ func (cfg *ExternalAMcfg) headerString() string {
 	return result.String()
 }
 
-func NewExternalAlertmanagerSender(l log.Logger, opts ...Option) *ExternalAlertmanager {
+func NewExternalAlertmanagerSender(l log.Logger, reg prometheus.Registerer, opts ...Option) *ExternalAlertmanager {
 	sdCtx, sdCancel := context.WithCancel(context.Background())
 	s := &ExternalAlertmanager{
 		logger:   l,
@@ -90,7 +90,7 @@ func NewExternalAlertmanagerSender(l log.Logger, opts ...Option) *ExternalAlertm
 	s.manager = NewManager(
 		// Injecting a new registry here means these metrics are not exported.
 		// Once we fix the individual Alertmanager metrics we should fix this scenario too.
-		&Options{QueueCapacity: defaultMaxQueueCapacity, Registerer: prometheus.NewRegistry()},
+		&Options{QueueCapacity: defaultMaxQueueCapacity, Registerer: reg},
 		s.logger,
 	)
 

pkg/services/ngalert/sender/sender_test.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/prometheus/alertmanager/api/v2/models"
+	"github.com/prometheus/client_golang/prometheus"
 	"github.com/prometheus/prometheus/model/labels"
 	"github.com/stretchr/testify/require"
 )
@@ -50,7 +51,7 @@ func TestSanitizeLabelName(t *testing.T) {
 
 	for _, tc := range cases {
 		logger := log.New("ngalert.sender.external-alertmanager")
-		am := NewExternalAlertmanagerSender(logger)
+		am := NewExternalAlertmanagerSender(logger, prometheus.NewRegistry())
 		t.Run(tc.desc, func(t *testing.T) {
 			res, err := am.sanitizeLabelName(tc.labelName)
 
@@ -98,7 +99,7 @@ func TestSanitizeLabelSet(t *testing.T) {
 
 	for _, tc := range cases {
 		logger := log.New("ngalert.sender.external-alertmanager")
-		am := NewExternalAlertmanagerSender(logger)
+		am := NewExternalAlertmanagerSender(logger, prometheus.NewRegistry())
 		t.Run(tc.desc, func(t *testing.T) {
 			require.Equal(t, tc.expectedResult, am.sanitizeLabelSet(tc.labelset))
 		})