Header.js

import React from "react";
import { connect } from "react-red";
import { Link } from "react-router-dom";

export const Header = ({ user }) => {
  return (
    <>
      {user.isSignedIn ? (
        <Link to="/logout">Logout</Link>
      ) : (
        <Link to="/login">To Login Page</Link>
      )}
      {user.isSignedIn && <Link to="/restricted">To Restricted Page</Link>}
      {user.role === "teacher" && (
        <Link to="/only-teacher">To Only Teacher Page</Link>
      )}
      {user.role === "student" && (
        <Link to="/only-student">To Only Student Page</Link>
      )}
    </>
  );
};

const mapStateToProps = state => ({
  user: state.userReducer
});

export default connect(
  mapStateToProps,
  null
)(Header);