I am having problem with a useEffect inside a ponent which is in every ponent. I have made some authentication and redirects in that ponent but I figured that when I use Nextjs link or the go back button from the browser, the Layout useEffect is not re rendering which means it is not checking if the user is logged in for example.

here's my layout ponent

const Layout = ({ children }) => {

  const router = useRouter()
  const { setAuthenticated, userFromDB, setUserFromDB, setIsVender, isVender } = useContext(AuthContext)

  //cuando hacemos un login el token se guarda en el local storage asi que probamos que exista
  useEffect(() => {
    const checkToken = async () => {
      const token = localStorage.getItem('FBIdToken')
      if (token) {
        const decodedToken = jwtDecode(token);
        //si la fecha de expiracion del token supero a la actual, redirect al login
        if (decodedToken.exp * 1000 < Date.now()) {
          setAuthenticated(false)
          router.replace('/login');
        } else {
          if(!userFromDB){
            const user = await getUser(decodedToken.user_id);
            //si encontro un usuario, lo asignamos al context api
            if(user){
              console.log(user)
              //  obtenemos el objecto con los datos del usuario y seteamos en el context si es vendedor o no
              if(typeof user.isVender !== undefined){
                user.isVender ? setIsVender(true) : setIsVender(false);
              }
              setUserFromDB(user);
            }
            setAuthenticated(true)
          }
        }
        console.log('ejecutando');
      } else {
        if(router.pathname !== "/" && 
            router.pathname !== "/download-app" && 
            router.pathname !== "/register" && 
            router.pathname !== "/login"
          ) {
          console.log(router.pathname, 'redirigiendo')
          router.replace('/login')
        }
        
      }
    }
    //probamos que haya un token y redirigimos al usuario en base a el
    checkToken();
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [isVender])


  return (
    <div>
      {children}
    </div>
  )
}

this is how I import it inside the _app.js ponent

  return (
    <AuthProvider>
      <Layout>
        <Component {...pageProps} />
      </Layout>
    </AuthProvider>
  )
}

I hope you can help me, thanks in advance!

I am having problem with a useEffect inside a ponent which is in every ponent. I have made some authentication and redirects in that ponent but I figured that when I use Nextjs link or the go back button from the browser, the Layout useEffect is not re rendering which means it is not checking if the user is logged in for example.

here's my layout ponent

const Layout = ({ children }) => {

  const router = useRouter()
  const { setAuthenticated, userFromDB, setUserFromDB, setIsVender, isVender } = useContext(AuthContext)

  //cuando hacemos un login el token se guarda en el local storage asi que probamos que exista
  useEffect(() => {
    const checkToken = async () => {
      const token = localStorage.getItem('FBIdToken')
      if (token) {
        const decodedToken = jwtDecode(token);
        //si la fecha de expiracion del token supero a la actual, redirect al login
        if (decodedToken.exp * 1000 < Date.now()) {
          setAuthenticated(false)
          router.replace('/login');
        } else {
          if(!userFromDB){
            const user = await getUser(decodedToken.user_id);
            //si encontro un usuario, lo asignamos al context api
            if(user){
              console.log(user)
              //  obtenemos el objecto con los datos del usuario y seteamos en el context si es vendedor o no
              if(typeof user.isVender !== undefined){
                user.isVender ? setIsVender(true) : setIsVender(false);
              }
              setUserFromDB(user);
            }
            setAuthenticated(true)
          }
        }
        console.log('ejecutando');
      } else {
        if(router.pathname !== "/" && 
            router.pathname !== "/download-app" && 
            router.pathname !== "/register" && 
            router.pathname !== "/login"
          ) {
          console.log(router.pathname, 'redirigiendo')
          router.replace('/login')
        }
        
      }
    }
    //probamos que haya un token y redirigimos al usuario en base a el
    checkToken();
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [isVender])


  return (
    <div>
      {children}
    </div>
  )
}

this is how I import it inside the _app.js ponent

  return (
    <AuthProvider>
      <Layout>
        <Component {...pageProps} />
      </Layout>
    </AuthProvider>
  )
}

I hope you can help me, thanks in advance!

• javascript
• reactjs
• next.js

• 1 This: // eslint-disable-next-line react-hooks/exhaustive-deps is almost always an indication that there's a bug in the code. It's probably covering up the bug in your code. Don't do that unless you are sure that you are right and the lint rule is wrong. That effect will only re-run if isVender (whatever that is) changes. – Jared Smith Commented Jan 13, 2022 at 17:13
• I removed it and nothing happened, I think it was because of a warning but is gone now – Joaquín Varela Commented Jan 13, 2022 at 17:47

1 Answer 1

If you want useEffect to trigger on router changes, you must add it as a dependancy of your useEffect hook:

useEffect(() => {
   ...
}, [isVender, router.pathname])