Check if user is logged in React Js - reactjs

Question

Hello guys i have a JWT authentication in my react project i want to make a function to check if the user logged . My login function is like this :
export function login(data) {
const endpoint = '/api/auth/jwt/'
const csrfToken = cookie.load('csrftoken')
let thisComp = this
if (csrfToken !== undefined) {
let lookupOptions = {
method: "POST",
headers: {
'Content-Type': 'application/json'
},
body: JSON.stringify(data),
credentials: 'include'
}
fetch(endpoint, lookupOptions)
.then(function(response){
return response.json()
}).then(function(responseData){
console.log(responseData)
localStorage.token = responseData.token
localStorage.expires = responseData.expires // Store the token
console.log("Token Stored", localStorage.token)
console.log("Token Expires", responseData.expires)
refreshToken(data) // Put in to the refresh function
}).catch(function(error){
console.log("error", error)
})
}
}
and my function isLoggedIn is like this :
export function isLoggedIn() {
// Check if we have a token stored
if (localStorage.token !== undefined) {
// I also want to check if the token is still work and don't expire
// i have acces to the expiration date like this :
// localStorage.token == > Token Expires 2018-06-19T14:51:59.451703Z in
the console
// How can check if the token still work ?
return true
}
return false
}

Answer 1

Can't you just check the expires property you stored in your local storage and compare it to current Date ?
Other ways to handle it: store the expiration date in the token itself, then use a jwt decoding library to decode the token and extract it from there. If you are using refresh tokens you can simply wait for the server to return a 401 Unauthorized response and send the refresh token to request a new one.