Alerting: Prevent showing "Permissions denied" alert when not accurate (#74887)

* Change way of obtaining external datasources info

* Remove unneeded import

* Create function to getExternalDsAlertManagers in datasource srv

* Remove unused import

public/app/features/alerting/unified/components/rule-editor/notificaton-preview/useGetAlertManagersSourceNamesAndImage.tsx

@@ -1,7 +1,6 @@
 import { AlertmanagerChoice } from '../../../../../../plugins/datasource/alertmanager/types';
 import { alertmanagerApi } from '../../../api/alertmanagerApi';
-import { useExternalDataSourceAlertmanagers } from '../../../hooks/useExternalAmSelector';
-import { GRAFANA_RULES_SOURCE_NAME } from '../../../utils/datasource';
+import { getExternalDsAlertManagers, GRAFANA_RULES_SOURCE_NAME } from '../../../utils/datasource';
 
 export interface AlertManagerNameWithImage {
   name: string;
@@ -12,10 +11,11 @@ export const useGetAlertManagersSourceNamesAndImage = () => {
   //get current alerting config
   const { currentData: amConfigStatus } = alertmanagerApi.useGetAlertmanagerChoiceStatusQuery(undefined);
 
-  const externalDsAlertManagers: AlertManagerNameWithImage[] = useExternalDataSourceAlertmanagers().map((ds) => ({
-    name: ds.dataSource.name,
-    img: ds.dataSource.meta.info.logos.small,
+  const externalDsAlertManagers = getExternalDsAlertManagers().map((ds) => ({
+    name: ds.name,
+    img: ds.meta.info.logos.small,
   }));
+
   const alertmanagerChoice = amConfigStatus?.alertmanagersChoice;
   const alertManagerSourceNamesWithImage: AlertManagerNameWithImage[] =
     alertmanagerChoice === AlertmanagerChoice.Internal

public/app/features/alerting/unified/utils/datasource.ts

@@ -47,6 +47,10 @@ export function getAlertManagerDataSources() {
     .sort((a, b) => a.name.localeCompare(b.name));
 }
 
+export function getExternalDsAlertManagers() {
+  return getAlertManagerDataSources().filter((ds) => ds.jsonData.handleGrafanaManagedAlerts);
+}
+
 const grafanaAlertManagerDataSource: AlertManagerDataSource = {
   name: GRAFANA_RULES_SOURCE_NAME,
   imgUrl: 'public/img/grafana_icon.svg',