zto_generator 0.1.0

build_runner code generator for zto — generates ZtoSchema constants and validated fromMap functions from @Dto-annotated classes.

zto_generator

build_runner code generator for zto. It reads your @ZDto-annotated classes and generates the $<Dto>Schema constants used by zto for runtime validation and OpenAPI 3.0 schema generation.

You don't use this package directly — you add it as a dev_dependency and run build_runner. The annotations and the runtime API live in zto.

Installation

dependencies:
  zto: ^0.1.0

dev_dependencies:
  build_runner: ^2.4.0
  zto_generator: ^0.1.0

Usage

1. Annotate a DTO and add the part directive:

import 'package:zto/zto.dart';

part 'user_dto.g.dart'; // generated by zto_generator

@ZDto(description: 'Create a user')
class CreateUserDto with ZtoDto<CreateUserDto> {
  @ZString(example: 'Alice')
  @ZMinLength(2)
  final String name;

  @ZString()
  @ZEmail()
  final String email;

  const CreateUserDto({required this.name, required this.email});

  factory CreateUserDto.fromMap(Map<String, dynamic> map) => CreateUserDto(
        name: map['name'] as String,
        email: map['email'] as String,
      );
}

2. Run the generator:

dart run build_runner build --delete-conflicting-outputs

This produces user_dto.g.dart containing the $CreateUserDtoSchema constant:

final dto = $CreateUserDtoSchema.parse(body, CreateUserDto.fromMap);

Build-time validation

Incompatible annotations fail the build with a clear message instead of failing silently at runtime — e.g. applying @ZEmail() to a numeric field, or @ZMin() to a String.

See also

• zto — annotations + runtime validation
• dart_frog_open_api — turns the generated schemas into Swagger / Scalar docs for Dart Frog

License

MIT