json_factory_runtime_annotation 0.3.1

Annotations for json_factory_runtime_generator, a build-time JSON factory generator for json_serializable classes.

example/README.md

Example

Run dart run build_runner build with json_factory_runtime_generator and json_serializable to generate example.g.dart and the factory mixins.

import 'package:json_annotation/json_annotation.dart';
import 'package:json_factory_runtime_annotation/json_factory_runtime_annotation.dart';

part 'example.g.dart';

@JsonSerializable()
class User {
  final String id;
  final String name;

  const User({required this.id, required this.name});

  /// Registers `User` under the key `'user'` in the default
  /// `JsonFactoryMixin` mixin (decoded with `JsonFactoryMapper`). `toJson()` writes `"__type__": "user"`.
  @jsonFactoryKey()
  final String factoryKey = 'user';

  factory User.fromJson(Map<String, dynamic> json) => _$UserFromJson(json);
  Map<String, dynamic> toJson() => _$UserToJson(this);
}

/// Registered in a separate mixin, `ApiMixin` (decoded with `ApiMapper`). Its key used to be
/// 'purchase'; JSON with "__type__": "purchase" still decodes to `Order`.
@JsonSerializable()
class Order {
  final String id;

  const Order({required this.id});

  @jsonFactoryKey(mixin: 'ApiMixin', oldKeys: ['purchase'])
  final String factoryKey = 'order';

  factory Order.fromJson(Map<String, dynamic> json) => _$OrderFromJson(json);
  Map<String, dynamic> toJson() => _$OrderToJson(this);
}

A complete, runnable project is in the generator's example.