Flutter安全存储初始化插件flutter_secure_storage_with_init的使用

Flutter安全存储初始化插件flutter_secure_storage_with_init的使用

flutter_secure_storage_with_init 是一个 Flutter 插件，用于在安全存储中存储数据。它在不同平台上使用不同的安全机制：

• 对于 iOS，使用 Keychain。
• 对于 Android，使用 AES 加密，AES 密钥通过 RSA 加密，并将 RSA 密钥存储在 KeyStore 中。
• 对于 Linux，使用 libsecret。

获取开始

首先，在你的 Dart 文件中导入 flutter_secure_storage_with_init 包：

import 'package:flutter_secure_storage/flutter_secure_storage_with_init.dart';

创建一个 FlutterSecureStorage 实例并使用以下方法进行操作：

// 创建存储实例
final storage = FlutterSecureStorageWithInit();

// 读取值
String value = await storage.read(key: key);

// 读取所有值
Map<String, String> allValues = await storage.readAll();

// 删除值
await storage.delete(key: key);

// 删除所有值
await storage.deleteAll();

// 写入值
await storage.write(key: key, value: value);

配置Android版本

确保你的 minSdkVersion 设置为 >= 18：

android {
    ...
    defaultConfig {
        ...
        minSdkVersion 18
        ...
    }
}

注意：默认情况下，Android 会在 Google Drive 上备份数据，这可能会导致 java.security.InvalidKeyException: Failed to unwrap key 异常。你需要：

• 禁用自动备份：禁用自动备份。
• 排除共享偏好设置文件：排除共享偏好设置文件。

Linux

在构建项目时，需要安装 libsecret-1-dev 和 libjsoncpp-dev。运行应用时，需要 libsecret-1-0 和 libjsoncpp1。如果你使用 snapcraft 构建项目，可以使用以下配置：

parts:
  uet-lms:
    source: .
    plugin: flutter
    flutter-target: lib/main.dart 
    build-packages:
     - libsecret-1-dev
     - libjsoncpp-dev
    stage-packages:
     - libsecret-1-dev
     - libjsoncpp1-dev

集成测试

从 example 目录运行以下命令：

flutter drive --target=test_driver/app.dart

完整示例代码

以下是完整的示例代码，展示了如何使用 flutter_secure_storage_with_init 插件：

import 'dart:async';
import 'dart:io';
import 'dart:math';

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

void main() {
  runApp(MaterialApp(home: ItemsWidget()));
}

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

enum _Actions { deleteAll }
enum _ItemActions { delete, edit }

class _ItemsWidgetState extends State<ItemsWidget> {
  final _storage = FlutterSecureStorageWithInit();
  final _accountNameController = TextEditingController(text: 'flutter_secure_storage_service');

  List<_SecItem> _items = [];

  [@override](/user/override)
  void initState() {
    super.initState();

    _accountNameController.addListener(() => _readAll());
    _readAll();
  }

  Future<void> _readAll() async {
    final all = await _storage.readAll(
      iOptions: _getIOSOptions(),
    );
    setState(() {
      _items = all.entries
          .map((entry) => _SecItem(entry.key, entry.value))
          .toList(growable: false);
    });
  }

  void _deleteAll() async {
    await _storage.deleteAll(
      iOptions: _getIOSOptions(),
    );
    _readAll();
  }

  void _addNewItem() async {
    final String key = _randomValue();
    final String value = _randomValue();

    await _storage.write(
      key: key,
      value: value,
      iOptions: _getIOSOptions(),
    );
    _readAll();
  }

  IOSOptions _getIOSOptions() => IOSOptions(
        accountName: _getAccountName(),
      );

  String? _getAccountName() => _accountNameController.text.isEmpty ? null : _accountNameController.text;

  [@override](/user/override)
  Widget build(BuildContext context) => Scaffold(
        appBar: AppBar(
          title: Text('Plugin example app'),
          actions: <Widget>[
            IconButton(
                key: Key('add_random'),
                onPressed: _addNewItem,
                icon: Icon(Icons.add)),
            PopupMenuButton<_Actions>(
                key: Key('popup_menu'),
                onSelected: (action) {
                  switch (action) {
                    case _Actions.deleteAll:
                      _deleteAll();
                      break;
                  }
                },
                itemBuilder: (BuildContext context) =>
                    <PopupMenuEntry<_Actions>>[
                      PopupMenuItem(
                        key: Key('delete_all'),
                        value: _Actions.deleteAll,
                        child: Text('Delete all'),
                      ),
                    ])
          ],
        ),
        body: Column(
          children: [
            if (Platform.isIOS)
              Padding(
                padding: const EdgeInsets.symmetric(horizontal: 16),
                child: TextFormField(
                  controller: _accountNameController,
                  decoration: InputDecoration(labelText: 'kSecAttrService'),
                ),
              ),
            Expanded(
              child: ListView.builder(
                itemCount: _items.length,
                itemBuilder: (BuildContext context, int index) => ListTile(
                  trailing: PopupMenuButton(
                      key: Key('popup_row_$index'),
                      onSelected: (_ItemActions action) => _performAction(action, _items[index]),
                      itemBuilder: (BuildContext context) =>
                          <PopupMenuEntry<_ItemActions>>[
                            PopupMenuItem(
                              value: _ItemActions.delete,
                              child: Text(
                                'Delete',
                                key: Key('delete_row_$index'),
                              ),
                            ),
                            PopupMenuItem(
                              value: _ItemActions.edit,
                              child: Text(
                                'Edit',
                                key: Key('edit_row_$index'),
                              ),
                            ),
                          ]),
                  title: Text(
                    _items[index].value,
                    key: Key('title_row_$index'),
                  ),
                  subtitle: Text(
                    _items[index].key,
                    key: Key('subtitle_row_$index'),
                  ),
                ),
              ),
            ),
          ],
        ),
      );

  Future<void> _performAction(_ItemActions action, _SecItem item) async {
    switch (action) {
      case _ItemActions.delete:
        await _storage.delete(
          key: item.key,
          iOptions: _getIOSOptions(),
        );
        _readAll();
        break;
      case _ItemActions.edit:
        final result = await showDialog<String>(
            context: context,
            builder: (context) => _EditItemWidget(item.value));
        if (result != null) {
          await _storage.write(
            key: item.key,
            value: result,
            iOptions: _getIOSOptions(),
          );
          _readAll();
        }
        break;
    }
  }

  String _randomValue() {
    final rand = Random();
    final codeUnits = List.generate(20, (index) {
      return rand.nextInt(26) + 65;
    });

    return String.fromCharCodes(codeUnits);
  }
}

class _EditItemWidget extends StatelessWidget {
  _EditItemWidget(String text)
      : _controller = TextEditingController(text: text);

  final TextEditingController _controller;

  [@override](/user/override)
  Widget build(BuildContext context) {
    return AlertDialog(
      title: Text('Edit item'),
      content: TextField(
        key: Key('title_field'),
        controller: _controller,
        autofocus: true,
      ),
      actions: <Widget>[
        TextButton(
            key: Key('cancel'),
            onPressed: () => Navigator.of(context).pop(),
            child: Text('Cancel')),
        TextButton(
            key: Key('save'),
            onPressed: () => Navigator.of(context).pop(_controller.text),
            child: Text('Save')),
      ],
    );
  }
}

class _SecItem {
  _SecItem(this.key, this.value);

  final String key;
  final String value;
}