Environments 🌱

There are many ways that environments can be configured in a Dart Frog application. The easiest way is to use environment variables via the Dart SDK.

As seen in the dependency injection docs, middleware can be used to provide dependencies to an application.

Following this approach, the snippet shows how a database client can be configured with different environments.

Handler middleware(Handler handler) {
  return handler
      .use(provider<CardsRepository>((_) {
        return DatabaseClient(
          dbUrl: Platform.environment['DB_URL'],
          dbUser: Platform.environment['DB_USER'],
          dbPassword: Platform.environment['DB_PASSWORD'],
        );
      }),
    );
}

When running the server, these environment variables can be passed along directly to Dart Frog commands:

Development server:

DB_URL=... DB_USER=... DB_PASSWORD=... dart_frog dev

Production server:

DB_URL=... DB_USER=... DB_PASSWORD=... dart build/server.dart

These variables can also be exported in the current session:

EXPORT DB_URL=...
EXPORT DB_USER=...
EXPORT DB_PASSWORD=...

warning

Accessing variables through String.fromEnvironment in a Dart Frog application will not work.String.fromEnvironment is meant to accesses variables set by the Dart compiler or runtime, which does not apply to a Dart Frog application. Instead, use Platform.environment.