code: private void ajaxGetPermissions(final Project project, final HashMap<String, Object> ret) {
      final ArrayList<HashMap<String, Object>> permissions =
          new ArrayList<>();
      for (final Pair<String, Permission> perm : project.getUserPermissions()) {
        final HashMap<String, Object> permObj = new HashMap<>();
        final String userId = perm.getFirst();
        permObj.put("username", userId);
        permObj.put("permission", perm.getSecond().toStringArray());
  
        permissions.add(permObj);
      }
  
      ret.put("permissions", permissions);
    }
docs: this only returns user permissions, but not group permissions and proxy users