use futures_util::TryStreamExt;
use hyper::service::{make_service_fn, service_fn};
use hyper::{Body, Method, Request, Response, Server, StatusCode};
use futures::future::Future;
use crate::error::Error;
use crate::System;
/// This is our service handler. It receives a Request, routes on its
/// path, and returns a Future of a Response.
async fn echo(req: Request<Body>) -> Result<Response<Body>, Error> {
match (req.method(), req.uri().path()) {
// Serve some instructions at /
(&Method::GET, "/") => Ok(Response::new(Body::from(
"Try POSTing data to /echo such as: `curl localhost:3000/echo -XPOST -d 'hello world'`",
))),
// Simply echo the body back to the client.
(&Method::POST, "/echo") => Ok(Response::new(req.into_body())),
// Convert to uppercase before sending back to client using a stream.
(&Method::POST, "/echo/uppercase") => {
let chunk_stream = req.into_body().map_ok(|chunk| {
chunk
.iter()
.map(|byte| byte.to_ascii_uppercase())
.collect::<Vec<u8>>()
});
Ok(Response::new(Body::wrap_stream(chunk_stream)))
}
// Reverse the entire body before sending back to the client.
//
// Since we don't know the end yet, we can't simply stream
// the chunks as they arrive as we did with the above uppercase endpoint.
// So here we do `.await` on the future, waiting on concatenating the full body,
// then afterwards the content can be reversed. Only then can we return a `Response`.
(&Method::POST, "/echo/reversed") => {
let whole_body = hyper::body::to_bytes(req.into_body()).await?;
let reversed_body = whole_body.iter().rev().cloned().collect::<Vec<u8>>();
Ok(Response::new(Body::from(reversed_body)))
}
// Return the 404 Not Found for other routes.
_ => {
let mut not_found = Response::default();
*not_found.status_mut() = StatusCode::NOT_FOUND;
Ok(not_found)
}
}
}
pub async fn run_api_server(sys: &System, api_port: u16, shutdown_signal: impl Future<Output=()>) -> Result<(), hyper::Error> {
let addr = ([0, 0, 0, 0], api_port).into();
let service = make_service_fn(|_| async { Ok::<_, Error>(service_fn(echo)) });
let server = Server::bind(&addr).serve(service);
let graceful = server.with_graceful_shutdown(shutdown_signal);
println!("Listening on http://{}", addr);
graceful.await
}
