qwe.js

class Users {
  constructor(http) {
    this.http = http;
    this.cache = new Map();
  }

  get(id, next) {
    if (this.cache.has(id)) {
      next(this.cache.get(id));
    }

    return this.http.get(`/users/${id}`).then(user => {
      this.cache.set(id, user);
      next(user);
    });
  }
}

const fetchCurrentUser = (dispatch, getState, { users }) => {
  dispatch(currentUserFetching);
  users.get(id, user => {
    dispatch(currentUserFetched(user));
  });
}

function CurrentUser() {
  const dispatch = useDispatch();
  const currentUserID = useSelector(state => state.currentUserID);
  useEffect(() => dispatch(fetchCurrentUser()), [currentUserID]);

  return <User id={currentUserID} />;
}