keyed_form_gen 0.1.0

build_runner code generator for keyed_form_schema: turns a schema into immutable data models, keyed_form_core field references and type-safe validation functions.

example/lib/main.dart

// Uses the generated output of `tour_schema.dart`. Every name below —
// `TourSchema`, `StopSchema`, `TourFields`, `StopRef` — is generated by
// `keyed_form_gen` from the single `ks.object({...})` declaration in that file.
//
//   dart run build_runner build   # (re)generate lib/tour_schema.kfg.dart
//   dart run lib/main.dart

import 'tour_schema.dart';

void main() {
  // 1. Immutable data classes. `.create()` fills schema defaults and assigns
  //    a UUID `clientId` to every list row (so it is a `KeyedRow`).
  final tour = TourSchema.create(
    title: 'Ky',
    stops: [
      StopSchema.create(city: 'Kyoto', nights: 3),
      StopSchema.create(city: '', nights: 2),
    ],
  );
  print(tour.stops.map((s) => s.clientId).toList()); // two generated uuids

  // 2. Generated field references — write one field without rebuilding the
  //    whole aggregate. `stop(ref)` takes a record of clientId strings.
  final ref = (stop: tour.stops.first.clientId);
  final updated = TourFields.stop(ref).city.set(tour, 'Kyoto (Gion)');
  print(TourFields.stop(ref).city.getOrNull(updated)); // Kyoto (Gion)

  // `stop(ref)` itself is a reference to the whole row:
  print(TourFields.stop(ref).getOrNull(updated)?.nights); // 3

  // 3. Validation generated from the same schema — `FieldErrors` keyed by the
  //    same `FieldKey` the references carry.
  final errors = updated.validate(); // == TourSchema.validateData(updated)
  for (final key in errors.keys) {
    print('${key.toPath()}: ${errors.byKey(key)}');
  }
  //   title: Tour title needs at least 3 characters
  //   stops.['<uuid-of-second-stop>'].city: City is required
}