Dart ORM

Easy-to-use and easy-to-setup database ORM for dart.

It is in the very beginning stage of development and not ready for production use.

Any feedback is greatly appreciated.

Feel free to contribute!

Features

Annotations

Annotations could be used in-place:

import 'package:dart_orm/orm.dart' as ORM;

@ORM.DBTable('users')
class User extends ORM.Model {
  // Every field that needs to be stored in database should be annotated with @DBField
  @ORM.DBField()
  @ORM.DBFieldPrimaryKey()
  int id;

  @ORM.DBField()
  String givenName;

  // column name can be overridden
  @ORM.DBField('family_name')
  String familyName;
}

Or one can provide a target class for DBTable annotation. In such way one can store third-party classes in database without changing the original class definition.

// somelibrary.dart
class User {
  int id;
  String name;
}

// your code
import 'somelibrary.dart' as lib;

@ORM.Table('users', lib.User)
class DBUser {
  @ORM.DBField()
  int id;
  
  @ORM.DBField()
  String name;
}

// now User instances could be used like this:
lib.User u = new lib.User();
u.name = 'Name';
await ORM.insert(u);

// Note that DBUser is used only for annotation purposes and should not be used directly.

Types support

Any simple Dart type could be used: int/double/String/bool/DateTime.

Lists are supported and could be used as any other type just by annotating a property:

@ORM.DBTable('users')
class User {
  @ORM.DBField()
  List<String> emails;
}

References to other tables are not supported, but are in progress. Stay tuned!

Inserts and updates

Every ORM.Model has .save() method which will update/insert a new row.

If class instance has 'id' field with not-null value, .save() will execute 'UPDATE' statement with 'WHERE id = $id'.

If class instance has null 'id' field, 'INSERT' statement will be executed.

User u = new User();
u.givenName = 'Sergey';
u.familyName = 'Ustimenko';

var saveResult = await u.save();

This statement will be executed on save():

INSERT INTO users (
    given_name,
    family_name)
VALUES (
    'Sergey',
    'Ustimenko'
);

Queries

ORM has two classes for finding records: Find and FindOne.

Constructors receive a class that extend ORM.Model.

ORM.Find f = new ORM.Find(User)
  ..where(new ORM.LowerThan('id', 3)
    .and(new ORM.Equals('givenName', 'Sergey')
      .or(new ORM.Equals('familyName', 'Ustimenko'))
    )
  )
  ..orderBy('id', 'DESC')
  ..setLimit(10);

List foundUsers = await f.execute();

for(User u in foundUsers){
  print('Found user:');
  print(u);
}

This will result such statement executed on the database:

SELECT *
FROM users
WHERE id < 3 AND (given_name = 'Sergey' OR family_name = 'Ustimenko')
ORDER BY id DESC LIMIT 10

Multiple database adapters support

Server-side adapters:

https://github.com/ustims/DartORM-PostgreSQL

https://github.com/ustims/DartORM-MySQL

https://github.com/ustims/DartORM-MongoDB

To use an adapter install it with pub and do this:

import 'package:dart_orm_adapter_postgresql/dart_orm_adapter_postgresql.dart';
import 'package:dart_orm/dart_orm.dart' as orm;

main() {
  orm.AnnotationsParser.initialize();

  String connectionString =
      'postgres://<username>:<password>@localhost:5432/<dbname>';
      
  orm.DBAdapter postgresAdapter = new PostgresqlDBAdapter(connectionString);
  await postgresAdapter.connect();
  
  orm.addAdapter('postgres', postgresAdapter);
  orm.setDefaultAdapter('postgres');
  
  await orm.Migrator.migrate();
}

DartORM could also be used on client side with indexedDB:

https://github.com/ustims/DartORM-IndexedDB

Roadmap

• model relations (in progress)
• migration system