Alerting: Integration test for testing template via remote alertmanager (#92147)

* Add integration test for testing template

* Update drone signature

pkg/services/ngalert/remote/alertmanager_test.go

@@ -22,6 +22,7 @@ import (
 
 	"github.com/grafana/alerting/definition"
 	alertingModels "github.com/grafana/alerting/models"
+	"github.com/grafana/alerting/notify"
 	"github.com/grafana/grafana/pkg/infra/db"
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/infra/tracing"
@@ -739,6 +740,66 @@ func TestIntegrationRemoteAlertmanagerReceivers(t *testing.T) {
 	}, rcvs)
 }
 
+func TestIntegrationRemoteAlertmanagerTestTemplates(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping integration test")
+	}
+
+	amURL, ok := os.LookupEnv("AM_URL")
+	if !ok {
+		t.Skip("No Alertmanager URL provided")
+	}
+
+	tenantID := os.Getenv("AM_TENANT_ID")
+	password := os.Getenv("AM_PASSWORD")
+
+	cfg := AlertmanagerConfig{
+		OrgID:             1,
+		URL:               amURL,
+		TenantID:          tenantID,
+		BasicAuthPassword: password,
+		DefaultConfig:     defaultGrafanaConfig,
+	}
+
+	secretsService := secretsManager.SetupTestService(t, fakes.NewFakeSecretsStore())
+	m := metrics.NewRemoteAlertmanagerMetrics(prometheus.NewRegistry())
+	am, err := NewAlertmanager(cfg, nil, secretsService.Decrypt, NoopAutogenFn, m, tracing.InitializeTracerForTest())
+	require.NoError(t, err)
+
+	// Valid template
+	c := apimodels.TestTemplatesConfigBodyParams{
+		Alerts: []*amv2.PostableAlert{
+			{
+				Annotations: amv2.LabelSet{
+					"annotations_label": "annotations_value",
+				},
+				Alert: amv2.Alert{
+					Labels: amv2.LabelSet{
+						"labels_label:": "labels_value",
+					},
+				},
+			},
+		},
+		Template: `{{ define "test" }} {{ index .Alerts 0 }} {{ end }}`,
+		Name:     "test",
+	}
+	res, err := am.TestTemplate(context.Background(), c)
+
+	require.NoError(t, err)
+	require.Len(t, res.Errors, 0)
+	require.Len(t, res.Results, 1)
+	require.Equal(t, "test", res.Results[0].Name)
+
+	// Invalid template
+	c.Template = `{{ define "test" }} {{ index 0 .Alerts }} {{ end }}`
+	res, err = am.TestTemplate(context.Background(), c)
+
+	require.NoError(t, err)
+	require.Len(t, res.Results, 0)
+	require.Len(t, res.Errors, 1)
+	require.Equal(t, notify.ExecutionError, res.Errors[0].Kind)
+}
+
 func genAlert(active bool, labels map[string]string) amv2.PostableAlert {
 	endsAt := time.Now()
 	if active {