useEffect causing render error when attempting to set state in app.js

I’ve got a useEffect in my app.js file, which attempts to set a ‘session’ state based upon the response from a function I’ve got.

const App = () => {

 const [session, setSession] = useState(null)

 useEffect(() => {
    supabase.auth.getSession()
    .then((response) => {
      setSession(response.data.session)
    })

    supabase.auth.onAuthStateChange((_event, session) => {
      setSession(session)
    })

  }, [session])

I then pass this state as a prop into my ‘Router’ component, like so:

<Route path="/dashboard/details" element={<PrivateRoute><DashboardDetails session={session}/></PrivateRoute>} />

Finally, in my component, I attempt to access the user’s id from the session data, and set it in ‘id’ state, passing props as a dependency in case the user’s id isn’t available on the first render:

useEffect(() => {
  const id = props.session.user.id
  setId(id)
}, [props])

However, it’s returning the following error:

Uncaught TypeError: Cannot read properties of null (reading ‘user’)

I know for definite that the session.user.id is the correct path to access it, but I can’t figure out what I’m doing wrong here.

>Solution :

need to check if the user is undefined or not. use the ? operator

useEffect(() => {
  const id = props.session?.user?.id
  if(id) setId(id)
}, [props.session])

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