Flutter授权认证插件flutter_appauth_platform_interface的使用

Flutter授权认证插件flutter_appauth_platform_interface的使用

1. 简介

flutter_appauth_platform_interface 是 flutter_appauth 插件的公共平台接口。它为 iOS 和 Android 提供了一个统一的接口，用于实现 OAuth 2.0 和 OpenID Connect 授权认证。通过这个接口，开发者可以在 Flutter 应用中轻松集成第三方登录和身份验证功能。

2. 安装

首先，在 pubspec.yaml 文件中添加 flutter_appauth 依赖：

dependencies:
  flutter:
    sdk: flutter
  flutter_appauth: ^4.5.0  # 请根据最新版本进行调整

然后，运行以下命令来安装依赖：

flutter pub get

3. 配置

3.1 iOS 配置

在 ios/Runner/Info.plist 文件中添加以下配置：

<key>CFBundleURLTypes</key>
<array>
  <dict>
    <key>CFBundleURLSchemes</key>
    <array>
      <string>your.bundle.id</string>
    </array>
  </dict>
</array>
<key>LSApplicationQueriesSchemes</key>
<array>
  <string>oauth2redirectgoogle</string>
  <string>com.googleusercontent.apps.your-client-id</string>
</array>

3.2 Android 配置

在 android/app/src/main/AndroidManifest.xml 文件中添加以下配置：

<activity
  android:name="net.openid.appauth.RedirectUriReceiverActivity"
  android:exported="true">
  <intent-filter>
    <action android:name="android.intent.action.VIEW" />
    <category android:name="android.intent.category.DEFAULT" />
    <category android:name="android.intent.category.BROWSABLE" />
    <data android:scheme="your.scheme" android:host="your.host" />
  </intent-filter>
</activity>

4. 使用示例

下面是一个完整的示例代码，展示了如何使用 flutter_appauth 进行 OAuth 2.0 授权认证。

4.1 主要代码

import 'package:flutter/material.dart';
import 'package:flutter_appauth/flutter_appauth.dart';
import 'package:flutter_secure_storage/flutter_secure_storage.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter AppAuth Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: AuthorizationScreen(),
    );
  }
}

class AuthorizationScreen extends StatefulWidget {
  [@override](/user/override)
  _AuthorizationScreenState createState() => _AuthorizationScreenState();
}

class _AuthorizationScreenState extends State<AuthorizationScreen> {
  final FlutterAppAuth _appAuth = FlutterAppAuth();
  final storage = FlutterSecureStorage();
  String? _authorizationCode;
  String? _accessToken;

  final String _clientId = 'your-client-id';
  final String _redirectUrl = 'your.scheme://your.host/callback';
  final String _discoveryUrl = 'https://accounts.google.com/.well-known/openid-configuration';

  Future<void> _authorize() async {
    try {
      final result = await _appAuth.authorizeAndExchangeCode(
        AuthorizationTokenRequest(
          _clientId,
          _redirectUrl,
          discoveryUrl: _discoveryUrl,
          scopes: ['openid', 'profile', 'email'],
        ),
      );

      if (result != null) {
        setState(() {
          _authorizationCode = result.authorizationCode;
          _accessToken = result.accessToken;
        });

        // 保存访问令牌到安全存储
        await storage.write(key: 'access_token', value: result.accessToken);
      }
    } catch (e) {
      print('Authorization failed: $e');
    }
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Flutter AppAuth Demo'),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            ElevatedButton(
              onPressed: _authorize,
              child: Text('Authorize'),
            ),
            SizedBox(height: 20),
            _authorizationCode != null
                ? Text('Authorization Code: $_authorizationCode')
                : Container(),
            SizedBox(height: 20),
            _accessToken != null
                ? Text('Access Token: $_accessToken')
                : Container(),
          ],
        ),
      ),
    );
  }
}