How to match Firebase User UID with Firestore Doc ID - Flutter - firebase

Question

I am new to flutter. So Please kindly bear with me.
I am creating a Real Estate App using Firebase and Provider.
I have two root Collections (1) "users" and (2) "properties"
I would like to achieve one specific task.
Although it seems like a simple task, yet I am still unable to solve it.
The task is to store Firebase User UID as Firestore Document ID of the rool Collection called "users" when the user sign up.
The problem I am having is the Firestore Document ID is automatically generated and its not Firebase User UID. Plus the field for userId appears null in Firestore.
Please see the screenshot of my database here
Thank you for your attention and time.
Here is my user_model.dart
class NayyaaUser {
String? uid;
String name;
String email;
String? phone;
NayyaaUser({this.uid, required this.name, required this.email, this.phone});
//send data to Firestore
Map<String, dynamic> toMap() {
return {
'userId': uid,
'userName': name,
'userEmail': email,
'userPhone': phone,
};
}
//draw data from firestore
factory NayyaaUser.fromFirestore(Map<String, dynamic> firestore) =>
NayyaaUser(
uid: firestore['userId'],
email: firestore['userEmail'] ?? " ",
name: firestore['userName'] ?? " ",
phone: firestore['userPhone'] ?? " ",
);
}
Here is my user_provider.dart
class UserProvider extends ChangeNotifier {
final firestoreService = FirestoreService();
final authService = AuthService();
String? _userId;
String? _name;
String? _email;
String? _phone;
//getters
String? get userId => _userId;
String? get name => _name;
String? get email => _email;
String? get phone => _phone;
//setters
changeName(String value) {
_name = value;
notifyListeners();
}
changeEmail(String value) {
_email = value;
notifyListeners();
}
changePhone(String value) {
_phone = value;
notifyListeners();
}
saveUserProfile() {
if (_userId == null) {
var updateUserProfile = NayyaaUser(
// userId: _userId,
uid: _userId,
name: name ?? '',
email: email ?? '',
phone: phone ?? '');
firestoreService.saveUserDataToFirestore(updateUserProfile);
} else {
var newUserProfile = NayyaaUser(
// userId: _userId,
uid: _userId,
name: name ?? '',
email: email ?? '',
phone: phone ?? '');
firestoreService.saveUserDataToFirestore(newUserProfile);
}
}
}
Here is auth_service.dart
class AuthService {
final FirebaseAuth _authInstance = FirebaseAuth.instance;
//create user obj based on "User" from Firebase
NayyaaUser? _userFromFirebase(User? user) {
return user != null
? NayyaaUser(
uid: user.uid,
name: '',
email: '',
phone: '',
)
: null;
}
// auth change user stream
Stream<NayyaaUser?> get userAuthStatus {
return _authInstance.authStateChanges().map(_userFromFirebase);
}
// sign in with email + password
Future signIn(String email, String password) async {
try {
UserCredential userAuthResult = await _authInstance
.signInWithEmailAndPassword(email: email, password: password);
User? user = userAuthResult.user;
return _userFromFirebase(user!);
} catch (e) {
// ignore: avoid_print
print(e.toString());
return null;
}
}
Future signUp(String email, String password) async {
try {
UserCredential userAuthResult = await _authInstance
.createUserWithEmailAndPassword(email: email, password: password);
User? user = userAuthResult.user;
return _userFromFirebase(user);
} catch (e) {
print(e.toString());
return null;
}
}
// sign out
Future signOut() async {
try {
return await _authInstance.signOut();
} catch (e) {
// ignore: avoid_print
print(e.toString());
return null;
}
}
}
Here is firestore_service.dart
class FirestoreService {
final CollectionReference _userRef =
FirebaseFirestore.instance.collection('users');
final CollectionReference _propertyRef =
FirebaseFirestore.instance.collection('properties');
//add or update user to firestore
Future<void> saveUserDataToFirestore(NayyaaUser nayyaaUserData) {
return _userRef.doc(nayyaaUserData.uid).set(nayyaaUserData.toMap());
}
// fetch user data from firestore
Stream<List<NayyaaUser>> getNayyaaUser() {
return _userRef.snapshots().map((snapshot) => snapshot.docs
.map((document) =>
NayyaaUser.fromFirestore(document.data() as Map<String, dynamic>))
.toList());
}
}

Answer 1

After login/signup successfully you can get user id from FirebaseAuth.instance.currentUser?.uid