mevn-mongodb-login-req: How to add route guard

[jsfanatik]

How do you add route guards to this app? I tried adding the following in the index.js:

router.beforeEach((to, from, next) => {
  const token = localStorage.usertoken
  const requiresAuth = to.matched.some(record => record.meta.requiresAuth)
  if (requiresAuth && !token) next('login')
  else if (!requiresAuth && token) next('profile')
  else next()
})
export default router

... in order to prevent the user from being logged out after refreshing the page, but to no avail. Any recommendations on how to add route guards?