fluo 3.3.2

Authentication made for Flutter. Complete UI flows in less than 5 minutes.

Fluo

📝 Looking for the full documentation? Check out the new Fluo SDK docs →

• Getting started
• More about the SDK
• Integrating with Firebase
• Integrating with Supabase
• Integrating with any backend
• Customizing the theme

Getting started

Add the package to your dependencies:

flutter pub add fluo

Add the FluoLocalizations.delegate to your app's localizationsDelegates:

MaterialApp(
  // ...other properties...
  localizationsDelegates: const [
    FluoLocalizations.delegate,
    // ...other delegates...
  ],
)

Use the Fluo SDK:

import 'package:fluo/fluo.dart';
import 'package:fluo/fluo_onboarding.dart';

FutureBuilder(
  // Get your api key from https://dashboard.fluo.dev (it's free)
  future: Fluo.init('YOUR_API_KEY'),
  builder: (context, snapshot) {
    // Check if Fluo is initialized.
    if (!Fluo.isInitialized) {
      return const Scaffold();
    }

    // Fluo is initialized. Check if the user is ready.
    if (!Fluo.instance.isUserReady()) {
      return FluoOnboarding(
        fluoTheme: FluoTheme.native(), // or FluoTheme.web()
        onUserReady: () => setState(() {}), // force build
      );
    }

    // User is ready!
    // An example `ConnectedScreen` widget is available in
    // the example/lib/main.dart file.
    return ConnectedScreen(
      onSignOut: () async {
        await Fluo.instance.clearSession();
        setState(() {});
      },
    );
  },
)

For macOS, make sure you have networking allowed by adding this key to both {your-app}/macos/Runner/DebugProfile.entitlements and {your-app}/macos/Runner/Release.entitlements:

<dict>
	<!-- Add this key set to true -->
	<key>com.apple.security.network.client</key>
	<true/>
</dict>

More about the SDK

Below are the most important methods to know:

// Initialize the SDK
await Fluo.init('YOUR_API_KEY');

// Check if init is done
if (Fluo.isInitialized) {
  // ...
}

// Check if user is ready (valid session + complete user attributes)
if (Fluo.instance.isUserReady()) {
  // ...
}

// Only check if a session exists
if (Fluo.instance.hasSession()) {
  // ...
}

// Get a certified fresh access token. "Certified fresh" means that
// if the access token has expired, Fluo will first refresh it before
// returning it. This is an important method if you selected a "custom"
// backend.
String accessToken = await Fluo.instance.getAccessToken();

// Force refresh the session. Generally, you should not need it because
// `Fluo.instance.getAccessToken()` handles refreshing the session.
await Fluo.instance.refreshSession();

// Clear the locally stored token. This is equivalent to a sign out.
await Fluo.instance.clearSession();

// User data
String userId = Fluo.instance.session.user.id; // "jzi8w7bdou4m0kq"
String email = Fluo.instance.session.user.email; // "[e-mail]"
String mobileE164 = Fluo.instance.session.user.mobileE164; // "[phone]"
String mobileIso2 = Fluo.instance.session.user.mobileIso2; // "US"
String firstName = Fluo.instance.session.user.firstName; // "Peter"
String lastName = Fluo.instance.session.user.lastName; // "Parker"

// If you build your own connect screen (and don't use FluoOnboarding)
// When authentication is done, these flows will automatically show the
// registration steps (you don't need to call `showRegisterFlow`).
Fluo.instance.showConnectWithEmailFlow(/* ... */)
Fluo.instance.showConnectWithMobileFlow(/* ... */)
Fluo.instance.showConnectWithGoogleFlow(/* ... */)
Fluo.instance.showConnectWithAppleFlow(/* ... */)

// Force show the registration steps. Generally, you should not need it.
Fluo.instance.showRegisterFlow(/* ... */)

Integrating with Firebase

Select 'Firebase' for your backend. Once complete, when users are onboarded, Fluo forwards their info to:

1. the Firebase Authentication service
2. a users table created automatically in the Firestore Database (make sure the Firestore Database is initialized)

Back to your app code, to initialize correctly the Firebase session, use the Fluo.instance.session.firebaseToken as below:

// 1. Initialize the Firebase client somewhere in your code
// 2. Make sure Fluo is initialized and has a session
// 3. Use 'signInWithCustomToken' as shown below
if (Fluo.isInitialized) {
  final fluoSession = Fluo.instance.session;
  if (fluoSession != null) {
    final firebaseToken = fluoSession.firebaseToken!;
    await FirebaseAuth.instance.signInWithCustomToken(firebaseToken);
  }
}

Integrating with Supabase

Select 'Supabase' for your backend. Once complete, when users are onboarded, Fluo forwards their info to:

1. the Supabase Authentication service
2. a users table that you will create as part of the Supabase setup (no worries, it's a simple copy-paste)

Back to your app code, to initialize correctly the Supabase session, use the Fluo.instance.session.supabaseSession as below:

// 1. Initialize the Supabase client somewhere in your code
// 2. Make sure Fluo is initialized and has a session
// 3. Use 'recoverSession' as shown below
if (Fluo.isInitialized) {
  final fluoSession = Fluo.instance.session;
  if (fluoSession != null) {
    final supabaseSession = fluoSession.supabaseSession!;
    await Supabase.instance.client.auth.recoverSession(supabaseSession);
  }
}

Integrating with any backend

Select 'Custom' for your backend. The general idea is to use the JWT access token provided by Fluo to get a unique user id via the "sub" JWT claim.

Here is a full example to understand how it works:

1. Wherever you need it, call Fluo.instance.getAccessToken() to get the JWT access token generated by Fluo and send it to your backend.

import 'dart:convert';
import 'package:http/http.dart' as http;

// Example of a function that gets a user. If the user
// doesn't exist yet, it should create it first.
Future<User> getOrCreateUser() async {
  final accessToken = await Fluo.instance.getAccessToken();
  final response = await http.post(
    Uri.parse('https://your-backend.com/api/user/me'),
    // Send the JWT access token to securely authenticate
    // the user and retrieve the user id.
    headers: {
      'authorization': 'Bearer $accessToken',
    },
    // Send the user data to create or update the user if
    // the object does not exist yet.
    body: jsonEncode(Fluo.instance.session.user),
  );
  return User.fromJson(jsonDecode(response.body));
}

2. In your backend, decode the access token to get the JWT payload.

const jwt = require("jsonwebtoken")

// This is your JWT secret key (do not share it with anyone)
// You can find it on https://dashboard.fluo.dev/backend
const SECRET_KEY = "YOUR_SECRET_KEY"

// Following on the example, here is the corresponding endpoint.
// Note that this is simplified and does not handle all edge cases.
app.post("/api/user/me", async (req, res) => {
  const accessToken = req.headers["authorization"].split(" ")[1]

  // Decode the access token using your secret key
  const payload = jwt.verify(accessToken, SECRET_KEY)

  // 'payload.sub' contains a unique user id generated by Fluo
  const userId = payload.sub

  // Find the user by id
  let user = await User.findOne({ id: userId }) // or { fluoId: userId }

  // If the user doesn't exist, create it
  if (!user) {
    const { email, mobileE164, mobileIso2, firstName, lastName } = req.body
    user = await User.create({
      id: userId,
      email: email,
      mobileE164: mobileE164,
      mobileIso2: mobileIso2,
      firstName: firstName,
      lastName: lastName,
    })
  }

  return res.status(200).json(user)
})

3. If you need to go further, here is a complete example of the payload. For example, for increased security, you might want to verify that the token has not expired.

{
  "sub": "2rztxukf57pnjz9", // user id
  "iat": 1744039599, // issued at
  "exp": 1744043199, // expires 1 hour after being issued
  "iss": "fluo.dev", // issuer
}

Customizing the theme

Pass a FluoTheme to the FluoOnboarding component.

For iOS, Android, macOS

FluoOnboarding(
  // ...other properties...
  fluoTheme: FluoTheme.native(/* parameters */),
)

For web

FluoOnboarding(
  // ...other properties...
  fluoTheme: FluoTheme.web(/* parameters */),
)

Parameters

{
  Color? primaryColor,
  Color? inversePrimaryColor,
  Color? accentColor,
  EdgeInsets? screenPadding,
  ButtonStyle? connectButtonStyle,
  ButtonStyle? connectButtonStyleGoogle,
  ButtonStyle? connectButtonStyleApple,
  TextStyle? connectButtonTextStyle,
  TextStyle? connectButtonTextStyleGoogle,
  TextStyle? connectButtonTextStyleApple,
  double? connectButtonIconSize,
  Widget? connectButtonIconEmail,
  Widget? connectButtonIconMobile,
  Widget? connectButtonIconGoogle,
  Widget? connectButtonIconApple,
  TextStyle? legalTextStyle,
  EdgeInsets? legalTextPadding,
  TextStyle? modalTitleTextStyle,
  TextStyle? titleStyle,
  InputDecorationTheme? inputDecorationTheme,
  TextStyle? inputTextStyle,
  TextStyle? inputErrorStyle,
  TextAlignVertical? inputTextAlignVertical,
  ButtonStyle? continueButtonStyle,
  Size? continueButtonProgressIndicatorSize,
  Color? continueButtonProgressIndicatorColor,
  double? continueButtonProgressIndicatorStrokeWidth,
  EdgeInsets? countryItemPadding,
  Color? countryItemHighlightColor,
  TextStyle? countryTextStyle,
  PinTheme? codeInputThemeDefault,
  PinTheme? codeInputThemeFocused,
  PinTheme? codeInputThemeSubmitted,
  PinTheme? codeInputThemeFollowing,
  PinTheme? codeInputThemeDisabled,
  PinTheme? codeInputThemeError,
}