Option to generate encoder/decoder for enum?

[PiN73]

Currently one can't decode/encode enum values directly from/to string.

For example, I have

enum State {
  @JsonValue('in_review')
  inReview,

  ...
}

and want to do this

String s = 'in_review';
State state = stateFromString(s);

I need either implement stateFromString manually (which will duplicate strings in @JsonValue) or make a wrapper class.

It would be great to have an option to generate from/to string converters by some annotation, e.g.

@JsonSerializable()
enum State {
  ...

[PiN73]

Maybe the generator can also reuse this generated function (like stateFromString and stateFromString) in fromJson/toJson for classes, e.g. if there is

class Article {
  State state;
  ...
}

inside another file

[PiN73]

Also it would be great to have one place for setting unknownEnumValue, e.g.

@JsonEnumSerializable(unknownEnumValue: State.unknown)
enum State {
  ...

which will be used as default in stateFromString/stateFromString functions with possibility to override it

[LichKing-2234]

You can follow this.
#653 (comment)

[kevmoo]

I have an idea for this, but we'll need to wait for Dart 2.14

[kevmoo]

WIP: #989

[kevmoo]

Landed in https://pub.dev/packages/json_serializable/versions/6.0.0

[HJ29]

Is it possible to convert enum to json value?
eg,

enum StatusCode {
  @JsonValue(200)
  success,
  @JsonValue('500')
  weird,
}

Sometime, I want to display the 200 value, but I cant find a way to decode StatusCode.success to json value 200.
json_serializable use _$EnumNameEnumMap and _$enumDecode to decode, but these aren't exposed to public,
so I cant use same way to decode.