supabase_schema_generator #

The code generator for the Supabase Schema Library. This package processes your schema definitions and generates type-safe Dart models (using freezed), strongly-typed IDs, and smart select statements.

Installation #

Add this package to your dev_dependencies in pubspec.yaml:

dev_dependencies:
  supabase_schema_generator: latest_version
  build_runner: latest_version
  freezed: latest_version
  json_serializable: latest_version

How it Works #

1. Define Schema: You define your schema using supabase_schema classes.
2. Run lean_builder: First run dart run lean_builder build to generate the base .supabase.dart file.
   • This step creates the intermediate file that contains your schema definitions, typed IDs, and select statements
3. Run build_runner: Then run dart run build_runner build to process the generated file and create the final models.
   • This step reads the .supabase.dart file and generates the final freezed models, JSON serialization, etc.
4. Generated Output: The process produces:
   • Base Schema File (.supabase.dart): Contains typed IDs, constants, and select statements
   • Freezed Models: Immutable data classes with JSON serialization (generated by build_runner)
   • Typed IDs: extension type wrappers around IDs (e.g., UserId) for type safety
   • Constants: Table names, column keys
   • Select Columns: A smart getter selectColumns that generates the correct Supabase select string, including nested joins

Generated Code Example #

For a User model, it generates:

extension type UserId._(int id) {
  factory UserId.fromJson(dynamic value) => ...
  int toJson() => id;
}

@freezed
sealed class User with _$User {
  const factory User({
    @JsonKey(name: "id") required UserId id,
    @JsonKey(name: "name") required String name,
    // ...
  }) = _User;

  static const String tableName = "users";
  
  // Smart select string with joins
  static String get selectColumns => 'id,name,...';
}

Complex Types #

Nested generic field types are supported and generated into the Freezed factory with the usual @JsonKey mapping, e.g.:

@Schema(tableName: 'products')
class ProductSchema extends SupabaseSchema {
  final variants = Field<List<Map<String, dynamic>>>('variants');
  final options = Field<Map<String, dynamic>>('options');
  final tags = Field<List<String>?>('tags');

  @override
  List<Model> get models => [
    Model('ProductDetailModel').fields([variants, options, tags]),
  ];
}