smf_dart_define 0.7.0

The SMF module that gives the Flutter app that SMF generates the values of its .env file with --dart-define-from-file of the flutter tool.

example/README.md

Generate a Flutter app that reads the values of .env

dart_define is the module of the SMF CLI that gives an app the values of its .env file through --dart-define-from-file, an option of the flutter tool. Choose it with -m:

dart pub global activate smf_flutter_cli
smf create my_app -m dart_define --no-input

The modules of an app declare the values that a developer fills in, as keys of the env role. The role writes .env with one line for each key, such as SHOP_API_KEY=, and .env.example, which has the same keys and stays in git while .env does not. This module adds lib/core/env/app_env.dart, with a static getter of AppEnv for each key:

abstract final class AppEnv {
  /// The public API key of the shop.
  static String? get shopApiKey {
    const value = String.fromEnvironment('SHOP_API_KEY');
    return value.isEmpty ? null : value;
  }
}

A getter is null while its value in .env is empty or missing, so the app builds and starts before you fill anything in. Fill in .env and run the app with the argument that reads it:

flutter run --dart-define-from-file=.env

flutter test and flutter build take the same argument. In VS Code, .vscode/launch.json passes it to Run and Debug, to the links above main() and to the tests. In Android Studio, .run/main.run.xml passes it to the run configuration named after the app, but not to tests. The flutter tool reads .env only when a command starts, so after you edit it, stop flutter run and start it again: hot reload and hot restart keep the old values.

Every value ends up in the app, where anyone who has the app can read it. Never put a secret into .env.

The documentation has more on the dart_define module.