DART

get one document firestore flutter dart

    var data;

    await usersCollection!
        .doc(user.uid)
        .get()
        .then((doc) => {data = doc.data()})
        .catchError((error) =>
            {print("Error on get data from User"), print(error.toString())});

    String firstname = data["firstname"];

flutter firestore get single document

DocumentSnapshot variable = await Firestore.instance.collection('COLLECTION NAME').document('DOCUMENT ID').get();