hyper_websocket_lite/
lib.rs

1#![warn(missing_docs)]
2#![warn(rust_2018_idioms)]
3
4//! A WebSocket server implementation on hyper and websocket-lite.
5
6use std::future::Future;
7
8use hyper::header::{self, HeaderValue};
9use hyper::upgrade::Upgraded;
10use hyper::{Body, Request, Response, StatusCode};
11use tokio::task;
12use tokio_util::codec::{Decoder, Framed};
13use websocket_codec::{ClientRequest, MessageCodec};
14
15pub use websocket_codec::Result;
16
17/// Exposes a `Sink` and a `Stream` for sending and receiving WebSocket messages asynchronously.
18pub type AsyncClient = Framed<Upgraded, MessageCodec>;
19
20/// Accepts a client's WebSocket Upgrade request.
21pub async fn server_upgrade<OnClient, F>(req: Request<Body>, on_client: OnClient) -> Result<Response<Body>>
22where
23    OnClient: FnOnce(AsyncClient) -> F + Send + 'static,
24    F: Future<Output = ()> + Send,
25{
26    let mut res = Response::new(Body::empty());
27
28    let ws_accept = if let Ok(req) = ClientRequest::parse(|name| {
29        let h = req.headers().get(name)?;
30        h.to_str().ok()
31    }) {
32        req.ws_accept()
33    } else {
34        *res.status_mut() = StatusCode::BAD_REQUEST;
35        return Ok(res);
36    };
37
38    task::spawn(async move {
39        match hyper::upgrade::on(req).await {
40            Ok(upgraded) => {
41                let client = MessageCodec::server().framed(upgraded);
42                on_client(client).await;
43            }
44            Err(e) => eprintln!("upgrade error: {}", e),
45        }
46    });
47
48    *res.status_mut() = StatusCode::SWITCHING_PROTOCOLS;
49
50    let headers = res.headers_mut();
51    headers.insert(header::UPGRADE, HeaderValue::from_static("websocket"));
52    headers.insert(header::CONNECTION, HeaderValue::from_static("Upgrade"));
53    headers.insert(header::SEC_WEBSOCKET_ACCEPT, HeaderValue::from_str(&ws_accept).unwrap());
54    Ok(res)
55}