Rework the implementation

README.md

@@ -27,7 +27,7 @@ import 'package:supabase_flutter/supabase_flutter.dart';
 void main() {
   WidgetsFlutterBinding.ensureInitialized();
 
-  Supabase(
+  Supabase.initialize(
     url: SUPABASE_URL,
     anonKey: SUPABASE_ANNON_KEY,
     authCallbackUrlHostname: 'login-callback', // optional
@@ -45,7 +45,7 @@ Now you can access Supabase client anywhere in your app.
 ```dart
 import 'package:supabase_flutter/supabase_flutter.dart';
 
-final response = await Supabase().client.auth.signIn(email: _email, password: _password);
+final response = await Supabase.instance.client.auth.signIn(email: _email, password: _password);
 ```
 
 #### SupabaseAuthState
@@ -67,8 +67,8 @@ For more details, take a look at the example [here](https://github.com/phamhieu/
 This method will automatically launch the auth url and open a browser for user to sign in with 3rd party login.
 
 ```dart
-Supabase().client.auth.signInWithProvider(
-  supabase.Provider.github,
+Supabase.instance.client.auth.signInWithProvider(
+  Provider.github,
   options: supabase.AuthOptions(redirectTo: ''),
 );
 ```
@@ -93,7 +93,8 @@ final localStorage = LocalStorage(
     const storage = FlutterSecureStorage();
     return storage.write(key: supabasePersistSessionKey, value: value);
   });
-Supabase(
+
+Supabase.initialize(
   ...
   localStorage: localStorage,
 );

lib/src/supabase.dart

@@ -4,60 +4,75 @@ import 'package:url_launcher/url_launcher.dart';
 
 const supabasePersistSessionKey = 'SUPABASE_PERSIST_SESSION_KEY';
 
-Future<bool> defHasAccessToken() async {
+Future<bool> _defHasAccessToken() async {
   final prefs = await SharedPreferences.getInstance();
   final exist = prefs.containsKey(supabasePersistSessionKey);
   return exist;
 }
 
-Future<String?> defAccessToken() async {
+Future<String?> _defAccessToken() async {
   final prefs = await SharedPreferences.getInstance();
   final jsonStr = prefs.getString(supabasePersistSessionKey);
   return jsonStr;
 }
 
-Future defRemovePersistedSession() async {
+Future _defRemovePersistedSession() async {
   final SharedPreferences prefs = await SharedPreferences.getInstance();
   return prefs.remove(supabasePersistSessionKey);
 }
 
-Future defPersistSession(String persistSessionString) async {
+Future _defPersistSession(String persistSessionString) async {
   final prefs = await SharedPreferences.getInstance();
   return prefs.setString(supabasePersistSessionKey, persistSessionString);
 }
 
 class LocalStorage {
-  LocalStorage(
-      {Future<bool> Function()? hasAccessToken,
-      Future<String?> Function()? accessToken,
-      Future Function()? removePersistedSession,
-      Future Function(String)? persistSession}) {
-    this.hasAccessToken = hasAccessToken ?? defHasAccessToken;
-    this.accessToken = accessToken ?? defAccessToken;
-    this.removePersistedSession =
-        removePersistedSession ?? defRemovePersistedSession;
-    this.persistSession = persistSession ?? defPersistSession;
-  }
-
-  Future<bool> Function() hasAccessToken = defHasAccessToken;
-  Future<String?> Function() accessToken = defAccessToken;
-  Future Function() removePersistedSession = defRemovePersistedSession;
-  Future Function(String) persistSession = defPersistSession;
+  /// Creates a `LocalStorage` instance
+  const LocalStorage({
+    this.hasAccessToken = _defHasAccessToken,
+    this.accessToken = _defAccessToken,
+    this.removePersistedSession = _defRemovePersistedSession,
+    this.persistSession = _defPersistSession,
+  });
+
+  final Future<bool> Function() hasAccessToken;
+  final Future<String?> Function() accessToken;
+  final Future Function() removePersistedSession;
+  final Future Function(String) persistSession;
 }
 
 class Supabase {
-  factory Supabase({
+  /// Gets the current supabase instance.
+  ///
+  /// An error is thrown if supabase isn't initialized yet
+  static Supabase get instance {
+    assert(
+      _instance._initialized,
+      'You must initialize the supabase instance before calling Supabase.instance',
+    );
+    return _instance;
+  }
+
+  /// Initialize the current supabase instance
+  ///
+  /// This must be called only once. If called more than once, an
+  /// [AssertionError] is thrown
+  factory Supabase.initialize({
     String? url,
     String? anonKey,
     String? authCallbackUrlHostname,
     bool? debug,
     LocalStorage? localStorage,
   }) {
+    assert(
+      !_instance._initialized,
+      'This instance is already initialized',
+    );
     if (url != null && anonKey != null) {
       _instance._init(url, anonKey);
       _instance._authCallbackUrlHostname = authCallbackUrlHostname;
       _instance._debugEnable = debug ?? false;
-      _instance._localStorage = localStorage ?? LocalStorage();
+      _instance._localStorage = localStorage ?? const LocalStorage();
       _instance.log('***** Supabase init completed $_instance');
     }
 
@@ -67,48 +82,37 @@ class Supabase {
   Supabase._privateConstructor();
   static final Supabase _instance = Supabase._privateConstructor();
 
-  SupabaseClient? _client;
+  bool _initialized = false;
+
+  /// The supabase client for this instance
+  late final SupabaseClient client;
   GotrueSubscription? _initialClientSubscription;
   bool _initialDeeplinkIsHandled = false;
   bool _debugEnable = false;
 
   String? _authCallbackUrlHostname;
-  LocalStorage _localStorage = LocalStorage();
+  LocalStorage _localStorage = const LocalStorage();
 
+  /// Dispose the instance
   void dispose() {
     if (_initialClientSubscription != null) {
       _initialClientSubscription!.data!.unsubscribe();
     }
+    _initialized = false;
   }
 
   void _init(String supabaseUrl, String supabaseAnonKey) {
-    if (_client != null) {
-      throw 'Supabase client is initialized more than once $_client';
-    }
-
-    _client = SupabaseClient(supabaseUrl, supabaseAnonKey);
+    client = SupabaseClient(supabaseUrl, supabaseAnonKey);
     _initialClientSubscription =
-        _client!.auth.onAuthStateChange(_onAuthStateChange);
-  }
-
-  SupabaseClient get client {
-    if (_client == null) {
-      throw 'Supabase client is not initialized';
-    }
-    return _client!;
+        client.auth.onAuthStateChange(_onAuthStateChange);
+    _initialized = true;
   }
 
-  LocalStorage get localStorage {
-    return _localStorage;
-  }
+  LocalStorage get localStorage => _localStorage;
 
-  Future<bool> get hasAccessToken async {
-    return _localStorage.hasAccessToken();
-  }
+  Future<bool> get hasAccessToken => _localStorage.hasAccessToken();
 
-  Future<String?> get accessToken async {
-    return _localStorage.accessToken();
-  }
+  Future<String?> get accessToken => _localStorage.accessToken();
 
   void _onAuthStateChange(AuthChangeEvent event, Session? session) {
     log('**** onAuthStateChange: $event');
@@ -172,7 +176,8 @@ class Supabase {
 }
 
 extension GoTrueClientSignInProvider on GoTrueClient {
-  Future<bool> signInWithProvider(Provider? provider,
+  /// Signs the user in using a thrid parties providers.
+  Future<bool> signInWithProvider(Provider provider,
       {AuthOptions? options}) async {
     final res = await signIn(
       provider: provider,

lib/src/supabase_auth_required_state.dart

@@ -1,4 +1,4 @@
-import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
 import 'package:supabase/supabase.dart';
 import 'package:supabase_flutter/src/supabase.dart';
 import 'package:supabase_flutter/src/supabase_state.dart';
@@ -10,22 +10,22 @@ abstract class SupabaseAuthRequiredState<T extends StatefulWidget>
   void initState() {
     super.initState();
 
-    if (Supabase().client.auth.currentSession == null) {
+    if (Supabase.instance.client.auth.currentSession == null) {
       _recoverSupabaseSession();
     } else {
-      onAuthenticated(Supabase().client.auth.currentSession!);
+      onAuthenticated(Supabase.instance.client.auth.currentSession!);
     }
   }
 
   @override
   void startAuthObserver() {
-    Supabase().log('***** SupabaseAuthRequiredState startAuthObserver');
+    Supabase.instance.log('***** SupabaseAuthRequiredState startAuthObserver');
     WidgetsBinding.instance?.addObserver(this);
   }
 
   @override
   void stopAuthObserver() {
-    Supabase().log('***** SupabaseAuthRequiredState stopAuthObserver');
+    Supabase.instance.log('***** SupabaseAuthRequiredState stopAuthObserver');
     WidgetsBinding.instance?.removeObserver(this);
   }
 
@@ -45,26 +45,27 @@ abstract class SupabaseAuthRequiredState<T extends StatefulWidget>
   }
 
   Future<bool> onResumed() async {
-    Supabase().log('***** SupabaseAuthRequiredState onResumed');
+    Supabase.instance.log('***** SupabaseAuthRequiredState onResumed');
     return _recoverSupabaseSession();
   }
 
   Future<bool> _recoverSupabaseSession() async {
-    final bool exist = await Supabase().localStorage.hasAccessToken();
+    final bool exist = await Supabase.instance.localStorage.hasAccessToken();
     if (!exist) {
       onUnauthenticated();
       return false;
     }
 
-    final String? jsonStr = await Supabase().localStorage.accessToken();
+    final String? jsonStr = await Supabase.instance.localStorage.accessToken();
     if (jsonStr == null) {
       onUnauthenticated();
       return false;
     }
 
-    final response = await Supabase().client.auth.recoverSession(jsonStr);
+    final response =
+        await Supabase.instance.client.auth.recoverSession(jsonStr);
     if (response.error != null) {
-      Supabase().localStorage.removePersistedSession();
+      Supabase.instance.localStorage.removePersistedSession();
       onUnauthenticated();
       return false;
     } else {

lib/src/supabase_auth_state.dart

@@ -1,4 +1,4 @@
-import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
 import 'package:supabase/supabase.dart';
 import 'package:supabase_flutter/src/supabase.dart';
 import 'package:supabase_flutter/src/supabase_state.dart';
@@ -10,21 +10,21 @@ abstract class SupabaseAuthState<T extends StatefulWidget>
     extends SupabaseState<T> with SupabaseDeepLinkingMixin {
   @override
   void startAuthObserver() {
-    Supabase().log('***** SupabaseAuthState startAuthObserver');
+    Supabase.instance.log('***** SupabaseAuthState startAuthObserver');
     startDeeplinkObserver();
   }
 
   @override
   void stopAuthObserver() {
-    Supabase().log('***** SupabaseAuthState stopAuthObserver');
+    Supabase.instance.log('***** SupabaseAuthState stopAuthObserver');
     stopDeeplinkObserver();
   }
 
   @override
   Future<bool> handleDeeplink(Uri uri) async {
-    if (!Supabase().isAuthCallbackDeeplink(uri)) return false;
+    if (!Supabase.instance.isAuthCallbackDeeplink(uri)) return false;
 
-    Supabase().log('***** SupabaseAuthState handleDeeplink $uri');
+    Supabase.instance.log('***** SupabaseAuthState handleDeeplink $uri');
 
     // notify auth deeplink received
     onReceivedAuthDeeplink(uri);
@@ -34,15 +34,15 @@ abstract class SupabaseAuthState<T extends StatefulWidget>
 
   @override
   void onErrorReceivingDeeplink(String message) {
-    Supabase().log('onErrorReceivingDeppLink message: $message');
+    Supabase.instance.log('onErrorReceivingDeppLink message: $message');
   }
 
   Future<bool> recoverSessionFromUrl(Uri uri) async {
-    final uriParameters = Supabase().parseUriParameters(uri);
+    final uriParameters = Supabase.instance.parseUriParameters(uri);
     final type = uriParameters['type'] ?? '';
 
     // recover session from deeplink
-    final response = await Supabase().client.auth.getSessionFromUrl(uri);
+    final response = await Supabase.instance.client.auth.getSessionFromUrl(uri);
     if (response.error != null) {
       onErrorAuthenticating(response.error!.message);
     } else {
@@ -58,21 +58,22 @@ abstract class SupabaseAuthState<T extends StatefulWidget>
   /// Recover/refresh session if it's available
   /// e.g. called on a Splash screen when app starts.
   Future<bool> recoverSupabaseSession() async {
-    final bool exist = await Supabase().localStorage.hasAccessToken();
+    final bool exist = await Supabase.instance.localStorage.hasAccessToken();
     if (!exist) {
       onUnauthenticated();
       return false;
     }
 
-    final String? jsonStr = await Supabase().localStorage.accessToken();
+    final String? jsonStr = await Supabase.instance.localStorage.accessToken();
     if (jsonStr == null) {
       onUnauthenticated();
       return false;
     }
 
-    final response = await Supabase().client.auth.recoverSession(jsonStr);
+    final response =
+        await Supabase.instance.client.auth.recoverSession(jsonStr);
     if (response.error != null) {
-      Supabase().localStorage.removePersistedSession();
+      Supabase.instance.localStorage.removePersistedSession();
       onUnauthenticated();
       return false;
     } else {
@@ -83,7 +84,7 @@ abstract class SupabaseAuthState<T extends StatefulWidget>
 
   /// Callback when deeplink received and is processing. Optional
   void onReceivedAuthDeeplink(Uri uri) {
-    Supabase().log('onReceivedAuthDeeplink uri: $uri');
+    Supabase.instance.log('onReceivedAuthDeeplink uri: $uri');
   }
 
   /// Callback when user is unauthenticated

lib/src/supabase_deep_linking_mixin.dart

@@ -1,7 +1,7 @@
 import 'dart:async';
 
 import 'package:flutter/foundation.dart';
-import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
 import 'package:flutter/services.dart';
 import 'package:supabase_flutter/src/supabase.dart';
 import 'package:uni_links/uni_links.dart';
@@ -10,13 +10,13 @@ mixin SupabaseDeepLinkingMixin<T extends StatefulWidget> on State<T> {
   StreamSubscription? _sub;
 
   void startDeeplinkObserver() {
-    Supabase().log('***** SupabaseDeepLinkingMixin startAuthObserver');
+    Supabase.instance.log('***** SupabaseDeepLinkingMixin startAuthObserver');
     _handleIncomingLinks();
     _handleInitialUri();
   }
 
   void stopDeeplinkObserver() {
-    Supabase().log('***** SupabaseDeepLinkingMixin stopAuthObserver');
+    Supabase.instance.log('***** SupabaseDeepLinkingMixin stopAuthObserver');
     if (_sub != null) _sub?.cancel();
   }
 
@@ -45,7 +45,7 @@ mixin SupabaseDeepLinkingMixin<T extends StatefulWidget> on State<T> {
   ///
   /// We handle all exceptions, since it is called from initState.
   Future<void> _handleInitialUri() async {
-    if (!Supabase().shouldHandleInitialDeeplink()) return;
+    if (!Supabase.instance.shouldHandleInitialDeeplink()) return;
 
     try {
       final uri = await getInitialUri();