Halt response transformer

[saantiaguilera]

Currently if we halt with a custom body we dont have any way to transform the response unless calling explicitly a transformation:

We have to do Spark.halt(HttpStatus.SC_BAD_REQUEST, responseTransformer.transform(message)); on each halt call

Could we have a feature like:

Spark.onErrorApply(responseTransformer); // Or a better name for the method

that applies to all exception messages?

Or at least be able to subscribe to events and tune it for all of the halts, like we can do with 404 or 500 or any particular exception except HaltException:

Spark.notFound(...); // Gets called
Spark.internalServerError(...); // Gets called
Spark.exception(HaltException.class, (ex, req, res) -> { // Wont get called
  res.status(ex.statusCode());
  res.body(responseTransformer.transform(ex.body()));
});