FurryChat/lib/utils/database/mobile.dart

78 lines
2.6 KiB
Dart

import 'dart:io';
import 'dart:isolate';
import 'package:famedlysdk/famedlysdk.dart';
import 'package:sqflite/sqflite.dart' show getDatabasesPath;
import 'package:path/path.dart' as p;
import 'package:flutter/material.dart';
import 'package:moor/moor.dart';
import 'package:moor/isolate.dart';
import 'cipher_db.dart' as cipher;
class DatabaseNoTransactions extends Database {
DatabaseNoTransactions.connect(DatabaseConnection connection)
: super.connect(connection);
// moor transactions are sometimes rather weird and freeze. Until there is a
// proper fix in moor we override that there aren't actually using transactions
@override
Future<T> transaction<T>(Future<T> Function() action) async {
return action();
}
}
bool _inited = false;
// see https://moor.simonbinder.eu/docs/advanced-features/isolates/
void _startBackground(_IsolateStartRequest request) {
// this is the entry point from the background isolate! Let's create
// the database from the path we received
if (!_inited) {
cipher.init();
_inited = true;
}
final executor = cipher.VmDatabaseEncrypted(File(request.targetPath),
password: request.password, logStatements: request.logStatements);
// we're using MoorIsolate.inCurrent here as this method already runs on a
// background isolate. If we used MoorIsolate.spawn, a third isolate would be
// started which is not what we want!
final moorIsolate = MoorIsolate.inCurrent(
() => DatabaseConnection.fromExecutor(executor),
);
// inform the starting isolate about this, so that it can call .connect()
request.sendMoorIsolate.send(moorIsolate);
}
// used to bundle the SendPort and the target path, since isolate entry point
// functions can only take one parameter.
class _IsolateStartRequest {
final SendPort sendMoorIsolate;
final String targetPath;
final String password;
final bool logStatements;
_IsolateStartRequest(
this.sendMoorIsolate, this.targetPath, this.password, this.logStatements);
}
Future<Database> constructDb(
{bool logStatements = false,
String filename = 'database.sqlite',
String password = ''}) async {
debugPrint('[Moor] using encrypted moor');
final dbFolder = await getDatabasesPath();
final targetPath = p.join(dbFolder, filename);
final receivePort = ReceivePort();
await Isolate.spawn(
_startBackground,
_IsolateStartRequest(
receivePort.sendPort, targetPath, password, logStatements),
);
final isolate = (await receivePort.first as MoorIsolate);
return DatabaseNoTransactions.connect(await isolate.connect());
}
Future<String> getLocalstorage(String key) async {
return null;
}