some questiones about the Service implemention of Router

[HunterGitHub]

for axum::Router，it implement the Service trait

impl<B> Service<Request<B>> for Router<(), B>
where
    B: HttpBody + Send + 'static,
{
    type Response = Response;
    type Error = Infallible;
    type Future = RouteFuture<B, Infallible>;

    #[inline]
    fn poll_ready(&mut self, _: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
        Poll::Ready(Ok(()))
    }

    #[inline]
    fn call(&mut self, req: Request<B>) -> Self::Future {
        self.call_with_state(req, ())
    }
}

but the type Response is Response<UnsyncBoxBody<Bytes, Error>> without generics，maybe it can be changed to type Response = Response<B> instead ? it could support more situations，for example，I want to get Response<hyper::Body> using

let req: Request<hyper::Body> = ...
let res: Response<hyper::Body> = router.call(req).await

[davidpdrsn]

maybe it can be changed to type Response = Response<B>

That's not possible because we cannot struct a B, so how would we make the response?

Response::new(???)

Therefore the response body type must be type erased so we can combine multiple types that we can construct.

[HunterGitHub]

thanks for your answer, I got it

[HunterGitHub]

there is some special cases that make me confused:

I start a hyper::Server and do some logic using hyper, but if the request info match some special case, I hope to use axum to handle the routing, serde, or some other complex logic, since axum router use UnsyncBoxBody, but hyper use its own hyper::Body, how can I make it work ?

Server::bind(&format!("0.0.0.0:{port}").parse().unwrap())
        .serve(make_service_fn(|_conn| async {
            Ok::<_, Infallible>(service_fn(handler))
        }))

async fn handler(mut req: Request<hyper::Body>) -> Result<Response<hyper::Body>, hyper::Error> {
       if match_some_case(&req) {
             // go axum logic
             return Ok(axum_router.call(req).await.unwrap())
       }

      // go hyper logic
}

[davidpdrsn]

Use axum::response::Response as the response type and create it by calling .into_resonse(). Like shown here

[HunterGitHub]

Thanks.