hasPermission role utility (#5554)

app/utils/role/index.ts

@@ -0,0 +1,14 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+import type RoleModel from '@typings/database/models/servers/role';
+
+export function hasPermission(roles: RoleModel[] | Role[], permission: string, defaultValue: boolean) {
+    const permissions = new Set<string>();
+    for (const role of roles) {
+        role.permissions.forEach(permissions.add, permissions);
+    }
+
+    const exists = permissions.has(permission);
+    return defaultValue === true || exists;
+}