postgres_utils 1.0.0 postgres_utils: ^1.0.0 copied to clipboard
A few utils for working with postgresql databases.
import 'package:logging_appenders/logging_appenders.dart';
import 'package:postgres/postgres.dart';
import 'package:postgres_utils/postgres_utils.dart';
import 'package:uuid/uuid.dart';
import 'package:uuid/uuid_util.dart';
import 'package:logging/logging.dart';
final _logger = Logger('main');
const Uuid _uuid = Uuid(options: <String, dynamic>{'grng': UuidUtil.cryptoRNG});
class DatabaseTransaction extends DatabaseTransactionBase<MyTables> {
DatabaseTransaction(PostgreSQLExecutionContext conn, MyTables tables)
: super(conn, tables);
}
class DatabaseAccess extends DatabaseAccessBase<DatabaseTransaction, MyTables> {
DatabaseAccess({
required DatabaseConfig config,
}) : super(
config: config,
tables: MyTables(),
migrations: MyMigrationsProvider(),
);
@override
DatabaseTransaction createDatabaseTransaction(
PostgreSQLExecutionContext conn, MyTables tables) {
return DatabaseTransaction(conn, tables);
}
}
class MyTables extends TablesBase {
MyTables();
late final UserTable user = UserTable();
@override
List<TableBase> get tables => [
user,
];
}
class UserTable extends TableBase {
UserTable();
static const TABLE_USER = 'example_user';
@override
List<String> get tables => [
TABLE_USER,
];
Future<void> createTables(DatabaseTransaction db) async {
await db.execute('''
CREATE TABLE $TABLE_USER (id uuid primary key, username varchar)
''');
}
Future<void> createUser(DatabaseTransactionBase db, String userName) async {
await db.executeInsert(TABLE_USER, {
'id': _uuid.v4(),
'username': userName,
});
}
}
class MyMigrationsProvider
extends MigrationsProvider<DatabaseTransaction, MyTables> {
@override
List<Migrations<DatabaseTransaction, MyTables>> get migrations {
return [
Migrations(
id: 1,
up: (conn) async {
await conn.tables.user.createTables(conn);
}),
];
}
}
Future<void> main() async {
PrintAppender.setupLogging();
const dbName = 'example_tmp';
final config = DatabaseConfig.fromEnvironment();
await _createDb(dbName, config);
final access = DatabaseAccess(config: config.copyWith(databaseName: dbName));
await access.prepareDatabase();
await access.run((db) async {
await db.tables.user.createUser(db, 'foo');
_logger.info('Successfully created user.');
});
await access.dispose();
}
Future<void> _createDb(String dbName, DatabaseConfig config) async {
final tmp = DatabaseAccess(
config: config,
);
// ignore: invalid_use_of_visible_for_testing_member
await tmp.forTestDropDatabase(dbName, ifExists: true);
// ignore: invalid_use_of_visible_for_testing_member
await tmp.forTestCreateDatabase(dbName);
await tmp.dispose();
}