How can I customize the error handling and error messages?

To customize error handling and error messages in Deepkit, you can listen to the httpWorkflow.onControllerError event and handle the error there. You can return a custom response with a specific HTTP status code and message. Here's an example:

import { HttpWorkflow, createHttpError, HttpResponse } from '@deepkit/http';

class MyError extends createHttpError(400, 'Custom Error') {}

app.listen(HttpWorkflow.onControllerError, (event) => {
  if (event.error instanceof MyError) {
    const response = new HttpResponse(event.error.message).status(event.error.status);
    event.send(response);
  }
});

In this example, we listen to the HttpWorkflow.onControllerError event and check if the error is an instance of MyError. If it is, we create a custom response with the error message and status code and send it back.

You can customize this logic further based on your specific error handling requirements.