# json_serializable 0.3.2

Generates utilities to aid in serializing to/from JSON.




## Installing
```
export PUB_HOSTED_URL=https://pub.mirror.p-hatan.ir
flutter pub add 'json_serializable:0.3.2'
```
Published: 2018-02-12T18:09:42.182356Z
Expected archive SHA-256: 8fc35438edf6984c84baa2e622d58079b950729821b357b97e05c83f1e08ba16

Available in cache; verification: upstream_checksum
## Direct dependencies
- analyzer: >=0.29.10 <0.32.0
- build: >=0.9.0 <0.13.0
- build_config: ^0.2.1
- cli_util: ^0.1.0
- json_annotation: >=0.2.2 <0.2.3
- path: ^1.3.2
- source_gen: ^0.7.5

## Package README (untrusted upstream documentation)
[![Build Status](https://travis-ci.org/dart-lang/json_serializable.svg?branch=master)](https://travis-ci.org/dart-lang/json_serializable)

Provides [source_gen] `Generator`s to create code for JSON serialization and
deserialization.

See the [example] package to understand how to configure your project.

## User defined and generated code

Given a library `example.dart` with an `Person` class annotated with
`@JsonSerializable()`:

```dart
library json_serializable.example;

import 'package:json_annotation/json_annotation.dart';
part 'example.g.dart';

@JsonSerializable()
class Person extends Object with _$PersonSerializerMixin {
  final String firstName;
  @JsonKey(includeIfNull: false)
  final String middleName;
  final String lastName;

  @JsonKey(name: 'date-of-birth', nullable: false)
  final DateTime dateOfBirth;

  @JsonKey(name: 'last-order')
  final DateTime lastOrder;

  @JsonKey(nullable: false)
  List<Order> orders;

  Person(this.firstName, this.lastName, this.dateOfBirth,
      {this.middleName, this.lastOrder, List<Order> orders})
      : this.orders = orders ?? <Order>[];

  factory Person.fromJson(Map<String, dynamic> json) => _$PersonFromJson(json);
}
```

Building creates the corresponding part `example.g.dart`:

```dart
Person _$PersonFromJson(Map<String, dynamic> json) => new Person(
    json['firstName'] as String,
    json['lastName'] as String,
    DateTime.parse(json['date-of-birth'] as String),
    middleName: json['middleName'] as String,
    lastOrder: json['last-order'] == null
        ? null
        : DateTime.parse(json['last-order'] as String),
    orders: (json['orders'] as List)
        .map((e) => new Order.fromJson(e as Map<String, dynamic>))
        .toList());

abstract class _$PersonSerializerMixin {
  String get firstName;
  String get middleName;
  String get lastName;
  DateTime get dateOfBirth;
  DateTime get lastOrder;
  List<Order> get orders;
  Map<String, dynamic> toJson() {
    var $map = <String, dynamic>{};
    void $writeNotNull(String key, dynamic value) {
      if (value != null) {
        $map[key] = value;
      }
    }

    $map['firstName'] = firstName;
    $writeNotNull('middleName', middleName);
    $map['lastName'] = lastName;
    $map['date-of-birth'] = dateOfBirth.toIso8601String();
    $map['last-order'] = lastOrder?.toIso8601String();
    $map['orders'] = orders;
    return $map;
  }
}
```

[example]: https://github.com/dart-lang/json_serializable/blob/master/example
[source_gen]: https://pub.dartlang.org/packages/source_gen

## Changelog
## 0.3.2

* The `require_library_directive` option now defaults to `false`.
  The option will be removed entirely in `0.4.0`.

## 0.3.1+2

* Support the latest version of the `analyzer` package.

## 0.3.1+1

* Expanded `package:build` support to allow version `0.12.0`.

## 0.3.1

* Add a `build.yaml` so the builder can be consumed by users of `build_runner`
  version 0.7.0.

* Now requires a Dart `2.0.0-dev` release.

## 0.3.0

* **NEW** top-level library `json_serializable.dart`.

  * Replaces now deprecated `generators.dart` to access
  `JsonSerializableGenerator` and `JsonLiteralGenerator`.
  
  * Adds the `jsonPartBuilder` function to make it easy to create a
    `PartBuilder`, without creating an explicit dependency on `source_gen`.

* **BREAKING** `UnsupportedTypeError` added a new required constructor argument:
  `reason`.

* **BREAKING** The deprecated `annotations.dart` library has been removed.
  Use `package:json_annotation` instead.

* **BREAKING** The arguments to `TypeHelper` `serialize` and `deserialize` have
  changed.
  * `SerializeContext` and `DeserializeContext` (new classes) are now passed
    instead of the `TypeHelperGenerator` typedef (which has been deleted).

* `JsonSerializableGenerator` now supports an optional `useWrappers` argument
  when generates and uses wrapper classes to (hopefully) improve the speed and
  memory usage of serialization – at the cost of more code.

  **NOTE**: `useWrappers` is not guaranteed to improve the performance of
  serialization. Benchmarking is recommended.

* Make `null` field handling smarter. If a field is classified as not
  `nullable`, then use this knowledge when generating serialization code –  even
  if `includeIfNull` is `false`.

## 0.2.5

* Throw an exception if a duplicate JSON key is detected.

* Support the `nullable` field on the `JsonSerializable` class annotation.

## 0.2.4+1

* Throw a more helpful error when a constructor is missing.

## 0.2.4

* Moved the annotations in `annotations.dart` to `package:json_annotations`.
  * Allows package authors to release code that has the corresponding 
    annotations without requiring package users to inherit all of the transitive
    dependencies.

* Deprecated `annotations.dart`.

## 0.2.3

* Write out `toJson` methods more efficiently when the first fields written are
  not intercepted by the null-checking method.

## 0.2.2+1

* Simplify the serialization of `Map` instances when no conversion is required
  for `values`.

* Handle `int` literals in JSON being assigned to `double` fields.

## 0.2.2

* Enable support for `enum` values.
* Added `asConst` to `JsonLiteral`.
* Improved the handling of Dart-specific characters in JSON strings.

## 0.2.1

* Upgrade to `package:source_gen` v0.7.0

## 0.2.0+1

* When serializing classes that implement their own `fromJson` constructor,
  honor their constructor parameter type.

## 0.2.0

* **BREAKING** Types are now segmented into their own libraries.

  * `package:json_serializable/generators.dart` contains `Generator` 
    implementations.

  * `package:json_serializable/annotations.dart` contains annotations.
    This library should be imported with your target classes.

  * `package:json_serializable/type_helpers.dart` contains `TypeHelper` classes
    and related helpers which allow custom generation for specific types. 

* **BREAKING** Generation fails for types that are not a JSON primitive or that
  do not explicitly supports JSON serialization. 

* **BREAKING** `TypeHelper`:

  * Removed `can` methods. Return `null` from `(de)serialize` if the provided
    type is not supported.

  * Added `(de)serializeNested` arguments to `(de)serialize` methods allowing
    generic types. This is how support for `Iterable`, `List`, and `Map`
    is implemented.

* **BREAKING** `JsonKey.jsonName` was renamed to `name` and is now a named
  parameter.

* Added support for optional, non-nullable fields.

* Added support for excluding `null` values when generating JSON.

* Eliminated all implicit casts in generated code. These would end up being
  runtime checks in most cases.

* Provide a helpful error when generation fails due to undefined types.

## 0.1.0+1

* Fix homepage in `pubspec.yaml`.

## 0.1.0

* Split off from [source_gen](https://pub.dartlang.org/packages/source_gen).

* Add `/* unsafe */` comments to generated output likely to be unsafe.

* Support (de)serializing values in `Map`.

* Fix ordering of fields when they are initialized via constructor.

* Don't use static members when calculating fields to (de)serialize.