How to exclude subkeys from ngrx-localstorage by angular service?

[mkvashennikov]

Me need to exclude user subkeys by currrent user platform in localStorageSyncReducer function.
How can i make this? (Me need to import external function from Angular service inside below function):

function localStorageSyncReducer(reducer: ActionReducer<any>): ActionReducer<any> {
  const rootKeys = Object.keys(initialAppState);
  const excludeUserFields = ['data', 'permissions'];
  if (environment.USE_SAFE_TOKEN) {
    excludeUserFields.push('token');
  }
  const keys = rootKeys.map((rootKey) => {
    const subKeys
      = rootKey === 'user'
        ? Object.keys(initialAppState[rootKey]).filter(
            (key) => excludeUserFields.indexOf(key) === -1,
          )
        : Object.keys(initialAppState[rootKey]);
    return { [rootKey]: subKeys };
  });

  return localStorageSync({ keys, rehydrate: true })(reducer);
}