ttl_etag_cache 1.0.4 
ttl_etag_cache: ^1.0.4 copied to clipboard
A powerful, reactive caching solution for Flutter with TTL, ETag support, and optional AES-256 encryption for offline-first applications.
import 'package:flutter/material.dart';
import 'package:ttl_etag_cache/ttl_etag_cache.dart';
void main() async {
WidgetsFlutterBinding.ensureInitialized();
// Initialize cache with encryption
await TtlEtagCache.init(enableEncryption: true);
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({super.key});
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Cache Demo',
theme: ThemeData(primarySwatch: Colors.blue, useMaterial3: true),
home: const HomeScreen(),
);
}
}
class HomeScreen extends StatelessWidget {
const HomeScreen({super.key});
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: const Text('Cache Examples')),
body: ListView(
children: [
ListTile(
title: const Text('User Profile'),
subtitle: const Text('Simple cached user data'),
trailing: const Icon(Icons.arrow_forward_ios),
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => const UserProfileScreen(userId: '1'),
),
);
},
),
ListTile(
title: const Text('Posts List'),
subtitle: const Text('List with pagination'),
trailing: const Icon(Icons.arrow_forward_ios),
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => const PostsListScreen(),
),
);
},
),
ListTile(
title: const Text('Combined Data'),
subtitle: const Text('Multiple repositories'),
trailing: const Icon(Icons.arrow_forward_ios),
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => const DashboardScreen(),
),
);
},
),
const Divider(),
ListTile(
title: const Text('Cache Settings'),
subtitle: const Text('Manage cache and encryption'),
trailing: const Icon(Icons.settings),
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => const CacheSettingsScreen(),
),
);
},
),
],
),
);
}
}
// Example 1: Simple User Profile
class UserProfileScreen extends StatefulWidget {
final String userId;
const UserProfileScreen({super.key, required this.userId});
@override
State<UserProfileScreen> createState() => _UserProfileScreenState();
}
class _UserProfileScreenState extends State<UserProfileScreen> {
late final CachedTtlEtagRepository<User> _repository;
@override
void initState() {
super.initState();
_repository = CachedTtlEtagRepository<User>(
config: CacheTtlEtagConfig<User>(
url: 'https://jsonplaceholder.typicode.com/users/${widget.userId}',
headers: {"accept": "application/json"},
fromJson: (json) => User.fromJson(json),
defaultTtl: const Duration(minutes: 5),
),
);
}
@override
void dispose() {
_repository.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('User Profile'),
actions: [
IconButton(
icon: const Icon(Icons.refresh),
onPressed: () => _repository.refresh(),
),
],
),
body: StreamBuilder<CacheTtlEtagState<User>>(
stream: _repository.stream,
builder: (context, snapshot) {
final state = snapshot.data ?? const CacheTtlEtagState<User>();
if (state.isEmpty && state.isLoading) {
return const Center(child: CircularProgressIndicator());
}
if (state.hasError && !state.hasData) {
return Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
const Icon(Icons.error_outline, size: 48, color: Colors.red),
const SizedBox(height: 16),
Text('Error: ${state.error}'),
const SizedBox(height: 16),
ElevatedButton(
onPressed: () => _repository.fetch(),
child: const Text('Retry'),
),
],
),
);
}
if (state.hasData) {
return Stack(
children: [
ListView(
children: [
if (state.isStale)
Container(
color: Colors.orange.shade100,
padding: const EdgeInsets.all(8),
child: const Row(
children: [
Icon(Icons.warning_amber, size: 16),
SizedBox(width: 8),
Text('Data is stale, refreshing...'),
],
),
),
Padding(
padding: const EdgeInsets.all(16),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Text(
state.data!.name,
style: Theme.of(context).textTheme.headlineMedium,
),
const SizedBox(height: 8),
Text(state.data!.email),
Text(state.data!.phone),
const SizedBox(height: 16),
if (state.timestamp != null)
Text(
'Last updated: ${state.timestamp!.toLocal()}',
style: const TextStyle(
fontSize: 12,
color: Colors.grey,
),
),
if (state.timeUntilExpiry != null)
Text(
'Expires in: ${state.timeUntilExpiry!.inMinutes} minutes',
style: const TextStyle(
fontSize: 12,
color: Colors.grey,
),
),
],
),
),
],
),
if (state.isLoading)
const Positioned(
top: 0,
left: 0,
right: 0,
child: LinearProgressIndicator(),
),
],
);
}
return const Center(child: Text('No data'));
},
),
);
}
}
// Example 2: Posts List
class PostsListScreen extends StatefulWidget {
const PostsListScreen({super.key});
@override
State<PostsListScreen> createState() => _PostsListScreenState();
}
class _PostsListScreenState extends State<PostsListScreen> {
late final CachedTtlEtagRepository<List<Post>> _repository;
@override
void initState() {
super.initState();
_repository = CachedTtlEtagRepository<List<Post>>(
config: CacheTtlEtagConfig<List<Post>>(
url: 'https://jsonplaceholder.typicode.com/posts',
method: "GET",
headers: {"accept": "application/json"},
fromJson: (json) =>
(json as List).map((e) => Post.fromJson(e)).toList(),
defaultTtl: const Duration(minutes: 10),
),
);
}
@override
void dispose() {
_repository.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('Posts'),
actions: [
IconButton(
icon: const Icon(Icons.refresh),
onPressed: () => _repository.refresh(),
),
],
),
body: StreamBuilder<CacheTtlEtagState<List<Post>>>(
stream: _repository.stream,
builder: (context, snapshot) {
final state = snapshot.data ?? const CacheTtlEtagState<List<Post>>();
if (state.isEmpty && state.isLoading) {
return const Center(child: CircularProgressIndicator());
}
if (state.hasData) {
return Stack(
children: [
RefreshIndicator(
onRefresh: () => _repository.refresh(),
child: ListView.builder(
itemCount: state.data!.length,
itemBuilder: (context, index) {
final post = state.data![index];
return ListTile(
title: Text(post.title),
subtitle: Text(
post.body,
maxLines: 2,
overflow: TextOverflow.ellipsis,
),
);
},
),
),
if (state.isLoading)
const Positioned(
top: 0,
left: 0,
right: 0,
child: LinearProgressIndicator(),
),
],
);
}
return const Center(child: Text('No posts'));
},
),
);
}
}
// Example 3: Dashboard with Multiple Data Sources
class DashboardScreen extends StatefulWidget {
const DashboardScreen({super.key});
@override
State<DashboardScreen> createState() => _DashboardScreenState();
}
class _DashboardScreenState extends State<DashboardScreen> {
late final CachedTtlEtagRepository<User> _userRepo;
late final CachedTtlEtagRepository<List<Post>> _postsRepo;
@override
void initState() {
super.initState();
_userRepo = CachedTtlEtagRepository<User>(
config: CacheTtlEtagConfig(
url: 'https://jsonplaceholder.typicode.com/users/1',
fromJson: (json) => User.fromJson(json),
defaultTtl: const Duration(minutes: 5),
),
);
_postsRepo = CachedTtlEtagRepository<List<Post>>(
config: CacheTtlEtagConfig(
url: 'https://jsonplaceholder.typicode.com/posts',
fromJson: (json) =>
(json as List).take(5).map((e) => Post.fromJson(e)).toList(),
defaultTtl: const Duration(minutes: 5),
),
);
}
@override
void dispose() {
_userRepo.dispose();
_postsRepo.dispose();
super.dispose();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('Dashboard'),
actions: [
IconButton(
icon: const Icon(Icons.refresh),
onPressed: () {
_userRepo.refresh();
_postsRepo.refresh();
},
),
],
),
body: StreamBuilder<CacheTtlEtagState<User>>(
stream: _userRepo.stream,
builder: (context, userSnapshot) {
return StreamBuilder<CacheTtlEtagState<List<Post>>>(
stream: _postsRepo.stream,
builder: (context, postsSnapshot) {
final userState =
userSnapshot.data ?? const CacheTtlEtagState<User>();
final postsState =
postsSnapshot.data ?? const CacheTtlEtagState<List<Post>>();
final isLoading = userState.isLoading || postsState.isLoading;
return Stack(
children: [
ListView(
children: [
if (userState.hasData)
Card(
margin: const EdgeInsets.all(16),
child: Padding(
padding: const EdgeInsets.all(16),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Text(
'Welcome, ${userState.data!.name}',
style: Theme.of(context).textTheme.titleLarge,
),
Text(userState.data!.email),
],
),
),
),
if (postsState.hasData)
Padding(
padding: const EdgeInsets.all(16),
child: Text(
'Recent Posts',
style: Theme.of(context).textTheme.titleMedium,
),
),
if (postsState.hasData)
...postsState.data!.map(
(post) => ListTile(
title: Text(post.title),
subtitle: Text(
post.body,
maxLines: 1,
overflow: TextOverflow.ellipsis,
),
),
),
],
),
if (isLoading)
const Positioned(
top: 0,
left: 0,
right: 0,
child: LinearProgressIndicator(),
),
],
);
},
);
},
),
);
}
}
// Cache Settings Screen
class CacheSettingsScreen extends StatefulWidget {
const CacheSettingsScreen({super.key});
@override
State<CacheSettingsScreen> createState() => _CacheSettingsScreenState();
}
class _CacheSettingsScreenState extends State<CacheSettingsScreen> {
bool _encryptionEnabled = false;
bool _isLoading = false;
@override
void initState() {
super.initState();
_encryptionEnabled = TtlEtagCache.isEncryptionEnabled;
}
Future<void> _toggleEncryption(bool value) async {
setState(() => _isLoading = true);
try {
await TtlEtagCache.migrateEncryption(enableEncryption: value);
setState(() {
_encryptionEnabled = value;
_isLoading = false;
});
if (mounted) {
ScaffoldMessenger.of(context).showSnackBar(
SnackBar(
content: Text(
value
? 'Encryption enabled successfully'
: 'Encryption disabled successfully',
),
),
);
}
} catch (e) {
setState(() => _isLoading = false);
if (mounted) {
ScaffoldMessenger.of(
context,
).showSnackBar(SnackBar(content: Text('Error: $e')));
}
}
}
Future<void> _clearCache() async {
await TtlEtagCache.clearAll();
if (mounted) {
ScaffoldMessenger.of(context).showSnackBar(
const SnackBar(content: Text('Cache cleared successfully')),
);
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: const Text('Cache Settings')),
body: ListView(
children: [
SwitchListTile(
title: const Text('Enable Encryption'),
subtitle: Text(
_encryptionEnabled
? 'Cache is encrypted with AES-256'
: 'Cache is stored in plain text',
),
value: _encryptionEnabled,
onChanged: _isLoading ? null : _toggleEncryption,
),
if (_isLoading) const LinearProgressIndicator(),
const Divider(),
ListTile(
title: const Text('Clear Cache'),
subtitle: const Text('Remove all cached data'),
trailing: const Icon(Icons.delete_outline),
onTap: _clearCache,
),
],
),
);
}
}
// Models
class User {
final int id;
final String name;
final String email;
final String phone;
User({
required this.id,
required this.name,
required this.email,
required this.phone,
});
factory User.fromJson(Map<String, dynamic> json) {
return User(
id: json['id'] as int,
name: json['name'] as String,
email: json['email'] as String,
phone: json['phone'] as String,
);
}
}
class Post {
final int id;
final int userId;
final String title;
final String body;
Post({
required this.id,
required this.userId,
required this.title,
required this.body,
});
factory Post.fromJson(Map<String, dynamic> json) {
return Post(
id: json['id'] as int,
userId: json['userId'] as int,
title: json['title'] as String,
body: json['body'] as String,
);
}
}Metadata
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likes
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points
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downloads
Publisher
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Metadata
A powerful, reactive caching solution for Flutter with TTL, ETag support, and optional AES-256 encryption for offline-first applications.
Repository (GitHub)
View/report issues
Documentation
License
MIT (license)
Dependencies
crypto, dio, encrypt, flutter, flutter_secure_storage, isar_community, isar_community_flutter_libs, path_provider, rxdart
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Packages that implement ttl_etag_cache
