[@react-router/serve] Serve additional files during npm run dev.

[Danielku15]

My usecase might be a bit special but I still hope react-router 7 can serve my needs.

I want to use react-router as framework for a "development playground" / "kitchen sink". During development of my library the playground/kitchen-sink can be used for different sort of tests and debugging needs. Here comes the challenge: The playground needs access to a bunch of files within the development workspace like test files to load.

How can I configure react-router to delegate HTTP requests to some custom handlers so I can process and serve the HTTP response. My two use-cases are:

a) I need to serve static files with the correct mime-types on a given route pattern. e.g. /test-data/{catchall} should serve any file from <repository-root>/assets/test. With this I want to serve any test files needed for fiddling with my library.

b) I need two API calls which I can call from my react app. In the first one I want to crawl some folders to visualize test results (snapshot diffs). In the second one I want to allow "accepting" a test results.

It would be quite easy if I can somehow register custom express middlewares but @react-router/serve seem to have no callback for this.

An important note: I currently have disabled SSR because I want the main application logic to run inside the browser.

What's the correct way to tackle this in react-router?