fix(dart_frog): Pipeline does not maintain RequestContext

[felangel]

Status

READY

Description

Currently, when using Dart Frog in a situation where middleware is applied, the RequestContext which the Handler is called with is not the same RequestContext which the Middleware is called with. This is problematic especially in tests because it is not possible to mock dependencies which are accessed via context.read from within middleware.

See the following example:

Future<Response> onRequest(RequestContext context, String id) async {
  Future<Response> handler(RequestContext context) async {
    final user = context.read<User>();
    return Response();
  }
  return handler.use(middleware)(context);
}

Middleware middleware(String id) {
  return (handler) {
    return (context) async {
      final database = context.read<Database>();
      final user = await database.getUserById(id);
      return handler(context.provide(() => user));
    };
  };
}

In the above example, the RequestContext in the middleware is not the same as the RequestContext in the handlers because dart frog creates a new RequestContext internally. This makes it impossible to mock context.read<Database>() in the above example.

Type of Change

• ✨ New feature (non-breaking change which adds functionality)
• 🛠️ Bug fix (non-breaking change which fixes an issue)
• ❌ Breaking change (fix or feature that would cause existing functionality to change)
• 🧹 Code refactor
• ✅ Build configuration change
• 📝 Documentation
• 🗑️ Chore