Flutter & Dart

1// lib/screens/login_screen.dart — the submit handler
2Future<void> signIn(String email, String password) async {
3  try {
4    await authix.loginUser(LoginParams(email: email, password: password));
5    await saveSession();
6    loggedIn.value = true;                       // the gate swaps screens
7  } on AuthenticationError {
8    showError('Wrong email or password');
9  } on NetworkError {
10    showError('Could not reach the server');
11  }
12}

1Future<void> signUp(String name, String email, String password) async {
2  await authix.signupUser(
3    SignupParams(name: name, email: email, password: password),
4  );
5
6  // Signup signs the user in already — the server issues the cookie.
7  await saveSession();
8
9  // But the account is not verified, and an unverified account cannot store
10  // records. Send the code straight away rather than failing on the first write.
11  final session = await authix.checkUserSession();
12  await authix.requestEmailVerificationOTP(
13    userId: session.userId!,
14    email: email,
15  );
16}
17
18Future<void> confirmCode(String email, String otp) async {
19  await authix.verifyEmail(email: email, otp: otp);
20  loggedIn.value = true;
21}

1Future<void> signOut() async {
2  try {
3    await authix.logoutUser();
4  } catch (_) {
5    // Ignore — the local session is cleared either way, so a logout on a bad
6    // connection cannot leave a usable session on the device.
7  }
8  await forgetSession();
9  loggedIn.value = false;
10}

1// lib/screens/notes_screen.dart
2class NotesScreen extends StatefulWidget {
3  const NotesScreen({super.key, required this.userId});
4  final String userId;
5
6  @override
7  State<NotesScreen> createState() => _NotesScreenState();
8}
9
10class _NotesScreenState extends State<NotesScreen> {
11  final _notes = <DataItem>[];
12  String? _cursor;
13  bool _hasMore = true;
14  bool _loading = false;
15
16  Future<void> _load() async {
17    if (_loading || !_hasMore) return;
18    setState(() => _loading = true);
19
20    final page = await authix.getUserData<DataItem>(
21      GetUserDataParams(
22        userId: widget.userId,
23        category: 'notes',
24        limit: 20,
25        cursor: _cursor,
26      ),
27      itemParser: DataItem.fromJson,
28    );
29
30    setState(() {
31      _notes.addAll(page);          // a Page is an Iterable of its records
32      _cursor = page.nextCursor;
33      _hasMore = page.hasMore;
34      _loading = false;
35    });
36  }
37
38  @override
39  void initState() {
40    super.initState();
41    _load();
42  }
43
44  @override
45  Widget build(BuildContext context) {
46    return ListView.builder(
47      itemCount: _notes.length + (_hasMore ? 1 : 0),
48      itemBuilder: (context, index) {
49        if (index == _notes.length) {
50          _load();                  // reached the end — fetch the next page
51          return const Center(child: CircularProgressIndicator());
52        }
53
54        final note = _notes[index];
55        return ListTile(
56          title: Text(note['title'] as String? ?? ''),
57          subtitle: Text('v${note.version}'),
58        );
59      },
60    );
61  }
62}

1// Or let the SDK follow the cursor and stream records as they arrive.
2StreamBuilder<DataItem>(
3  stream: authix.iterateUserData<DataItem>(
4    GetUserDataParams(userId: userId, category: 'notes'),
5    itemParser: DataItem.fromJson,
6    maxPages: 20,
7  ),
8  builder: (context, snapshot) {
9    // ... accumulate snapshot.data as it arrives
10  },
11);

1/// Tokens expire, and changing a password revokes every session for that user.
2/// So a call can fail even when the gate says "signed in". Handle it once.
3Future<T> guarded<T>(Future<T> Function() call) async {
4  try {
5    return await call();
6  } on NoUserSessionError {
7    await forgetSession();
8    loggedIn.value = false;        // the gate returns to the login screen
9    rethrow;
10  }
11}
12
13// use it
14final profile = await guarded(
15  () => authix.getUserProfile(userId: currentUserId),
16);

1import 'package:http/browser_client.dart';
2
3// On Flutter Web the browser owns the cookie jar and JavaScript cannot read an
4// HttpOnly cookie. Hand the client a BrowserClient and skip persistence.
5final authix = NeuctraAuthix(
6  config,
7  client: BrowserClient()..withCredentials = true,
8);

lib/
├── main.dart                    # restore session, then decide the first screen
├── services/
│   ├── authix.dart              # one client + secure-storage persistence
│   └── auth_state.dart          # ValueNotifier<bool> loggedIn
└── screens/
    ├── auth_gate.dart           # picks Home or Login
    ├── login_screen.dart
    ├── signup_screen.dart       # signup + OTP verification
    ├── home_screen.dart
    └── notes_screen.dart        # paged reads