auth

// Auth провайдер, обертка для прокидывания информации о пользователе
const AuthProvider = ({ children }) => {
  const currentUser = JSON.parse(localStorage.getItem('user'));

  const [user, setUser] = useState(currentUser ? { username: currentUser.username } : null);
  const logIn = (userData) => {
    localStorage.setItem('user', JSON.stringify(userData));
    setUser({ username: userData.username });
  };

  const logOut = () => {
    ...
  };

  const getAuthHeader = () => {
    ...
  };

  return (
    <AuthContext.Provider value={{
      logIn, logOut, getAuthHeader, user,
    }}
    >
      {children}
    </AuthContext.Provider>
  );
};

// на странице чата

const auth = useAuth();

useEffect(() => {
  const fetchData = async () => {
    try {
      const res = await axios.get(routes.dataPath(), { headers: auth.getAuthHeader() });
      ...
    } catch (err) {
      if (err.response?.status === 401) {
        navigate('/login');
      }
    }
    fetchData();
}, [auth, navigate]);