Add test and marker const for wrapper

cmd/alertmanager/main.go

@@ -385,7 +385,7 @@ func run() int {
 				level.Info(configLogger).Log("msg", "skipping creation of receiver not referenced by any route", "receiver", rcv.Name)
 				continue
 			}
-			integrations, err := receiver.BuildReceiverIntegrations(rcv, tmpl, logger)
+			integrations, err := receiver.BuildReceiverIntegrations(rcv, tmpl, logger, receiver.NoWrap)
 			if err != nil {
 				return err
 			}

notify/receiver/receiver.go

@@ -38,6 +38,8 @@ import (
 
 type Wrapper func(string, notify.Notifier) notify.Notifier
 
+var NoWrap Wrapper = nil
+
 // BuildReceiverIntegrations builds a list of integration notifiers off of a
 // receiver config.
 func BuildReceiverIntegrations(nc config.Receiver, tmpl *template.Template, logger log.Logger, wrap Wrapper, httpOpts ...commoncfg.HTTPClientOption) ([]notify.Integration, error) {
@@ -50,7 +52,9 @@ func BuildReceiverIntegrations(nc config.Receiver, tmpl *template.Template, logg
 				errs.Add(err)
 				return
 			}
-			n = wrap(name, n)
+			if wrap != nil {
+				n = wrap(name, n)
+			}
 			integrations = append(integrations, notify.NewIntegration(n, rs, name, i, nc.Name))
 		}
 	)

notify/receiver/receiver_test.go

@@ -71,7 +71,7 @@ func TestBuildReceiverIntegrations(t *testing.T) {
 	} {
 		tc := tc
 		t.Run("", func(t *testing.T) {
-			integrations, err := BuildReceiverIntegrations(tc.receiver, nil, nil)
+			integrations, err := BuildReceiverIntegrations(tc.receiver, nil, nil, NoWrap)
 			if tc.err {
 				require.Error(t, err)
 				return
@@ -85,4 +85,31 @@ func TestBuildReceiverIntegrations(t *testing.T) {
 			}
 		})
 	}
+
+	t.Run("invokes notifier wrapper func", func(t *testing.T) {
+		calls := 0
+		wrap := func(_ string, n notify.Notifier) notify.Notifier {
+			calls += 1
+			return n
+		}
+		cfg := config.Receiver{
+			Name: "foo",
+			WebhookConfigs: []*config.WebhookConfig{
+				{
+					HTTPConfig: &commoncfg.HTTPClientConfig{},
+				},
+				{
+					HTTPConfig: &commoncfg.HTTPClientConfig{},
+					NotifierConfig: config.NotifierConfig{
+						VSendResolved: true,
+					},
+				},
+			},
+		}
+
+		_, err := BuildReceiverIntegrations(cfg, nil, nil, wrap)
+		require.NoError(t, err)
+
+		require.Equal(t, 2, calls)
+	})
 }