create example.

Author: hpoul

CHANGELOG.md

@@ -1,3 +1,3 @@
 ## 1.0.0
 
-- Initial version, created by Stagehand
+- Initial version.

example/lib/main.dart

@@ -1,5 +1,14 @@
+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)
@@ -26,6 +35,7 @@ class MyTables extends TablesBase {
   MyTables();
 
   late final UserTable user = UserTable();
+
   @override
   List<TableBase> get tables => [
         user,
@@ -35,7 +45,7 @@ class MyTables extends TablesBase {
 class UserTable extends TableBase {
   UserTable();
 
-  static const TABLE_USER = 'user';
+  static const TABLE_USER = 'example_user';
 
   @override
   List<String> get tables => [
@@ -47,6 +57,13 @@ class UserTable extends TableBase {
     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
@@ -62,3 +79,29 @@ class MyMigrationsProvider
     ];
   }
 }
+
+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();
+}

example/pubspec.yaml

@@ -8,5 +8,7 @@ environment:
 
 dependencies:
   postgres: ^2.4.1+2
+  uuid: ^3.0.4
+  logging_appenders: ^1.0.0
   postgres_utils:
     path: ../

lib/src/config.dart

@@ -18,6 +18,8 @@ class DatabaseConfig {
   factory DatabaseConfig.fromJson(Map<String, dynamic> json) =>
       _$DatabaseConfigFromJson(json);
 
+  /// load database configuration from the `DBCONFIG` environment variables.
+  /// this environment variable must be a json.
   factory DatabaseConfig.fromEnvironment({DatabaseConfig? defaults}) =>
       DatabaseConfig.fromJson(_jsonFromEnvironment(defaults));
 

lib/src/database_access.dart

@@ -256,8 +256,10 @@ abstract class DatabaseAccessBase<TX extends DatabaseTransactionBase<TABLES>,
   }
 
   @visibleForTesting
-  Future<void> forTestDropDatabase(String databaseName) async {
-    await (await _connection()).execute('DROP DATABASE $databaseName');
+  Future<void> forTestDropDatabase(String databaseName,
+      {bool ifExists = false}) async {
+    await (await _connection()).execute(
+        'DROP DATABASE ${ifExists ? ' IF EXISTS ' : ''} $databaseName');
   }
 
   Future<void> dispose() async {