json_store
A Storage solution somewhat similar to a browser's localStorage in the sence that it is a key value pair storage. The value should be a dart reprisentation of a JSON Object (aka a Map<String, dynamic>)
Features
- Data is stored in sqflite Database
- Data may be fully encrypted (encrypt)
- Encryption keys are stored in Keychain and Keystore thanks to flutter_secure_storage
- Because the DB schema never changes, there is no concern about database migrations
- Batch processing
- Data stored has a time to live. Whenever a
getItem is done on a key which ttl has expired, that key will be deleted and a null value will be returned
Getting Started
In your flutter project add the dependency:
dependencies:
...
json_store:
...
For help getting started with Flutter, view the online documentation.
Usage example
See example folder for full sample app
Note: JsonStore is a singleton and instantiating with factory constructor JsonStore() will only ever have one instance
Simple example
import 'package:json_store/json_store.dart';
class CounterModel {
int value;
CounterModel(this.value);
CounterModel.fromJson(Map<String, dynamic> json) : this.value = json['value'];
Map<String, dynamic> toJson() => {'value': value};
}
...
JsonStore jsonStore = JsonStore();
CounterModel counter;
loadFromStorage() async {
Map<String, dynamic> json = await jsonStore.getItem('counter');
counter = json != null ? CounterModel.fromJson(json) : CounterModel(0);
}
incrementCounter() async {
counter.value++;
await jsonStore.setItem('counter', counter.toJson());
}
...
Batch example
When adding a lot of data at a time (Like a long list of messages), use the batch feature as it will improve performance significantly
class Message {
final int id;
final String title;
final String body;
Message([this.id, this.title, this.body]);
Message.fromJson(Map<String, dynamic> json)
: this.id = json['id'],
this.title = json['title'],
this.body = json['body'];
Map<String, dynamic> toJson() => {
'id': id,
'title': title,
'body': body,
};
}
saveBigList() {
Batch batch = await jsonStore.startBatch();
await Future.forEach(_messages, (message) async {
await jsonStore.setItem(
'messages-${message.id}',
message.toJson(),
batch: batch,
);
});
jsonStore.commitBatch(batch);
}
loadBigList() {
List<Map<String, dynamic>> json = await jsonStore.getListLike('messages-%');
messages = json != null
? json.map((messageJson) => Message.fromJson(messageJson)).toList()
: [];
}
Configure Android
In [project]/android/app/build.gradle set minSdkVersion to >= 18.
android {
...
defaultConfig {
...
minSdkVersion 18
...
}
}
Thanks
Thanks to contributors
