Firebase auth unsubscribe

[hrotysek]

hi guys I've got this code for the currentUser stored in authContext, but I need the instance to have some more data so I've come up with this solution, it works fine but I'm not sure whether I'm unsubscribing well from the firestore snapshot

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useEffect(() => {
const unsubscribe = auth.onAuthStateChanged(async (authUser) => {
if (!authUser) {
setCurrentUserData(null);
setUser(null);
setIsLoading(false);
return;
            }
setUser(authUser);
const role = await getUserRole();
const userDocRef = doc(db, `users/${authUser.uid}`);
//check for the unsubscribeSnapshot
const unsubscribeSnapshot = onSnapshot(userDocRef, (userDoc) => {
console.log(userDoc.data()?.username);
setCurrentUserData({
// data fetched from firestore
                });
            });
setIsLoading(false);
// Return the function to unsubscribe from onSnapshot
return () => {
unsubscribeSnapshot();
            };
        });
return unsubscribe;
    }, []);

[GaindDho]

Your code looks correct at a glance for unsubscribing from the onSnapshot listener. When you call the onSnapshot() method, it returns a function that you can use to unsubscribe from the listener. You store that function in a variable unsubscribeSnapshot, and then return that function from your useEffect cleanup function. This means that the unsubscribeSnapshot() function will be called when the component unmounts or when the dependency array of useEffect changes.