use std::io;
use bytes::Bytes;
use futures::{Async, AsyncSink, Future, Poll, Stream};
use tokio_io::{AsyncRead, AsyncWrite};
use tokio_service::Service;
use proto::{Body, Conn, Http1Transaction, MessageHead, RequestHead, ResponseHead};
use ::StatusCode;
pub struct Dispatcher<D, Bs, I, B, T> {
conn: Conn<I, B, T>,
dispatch: D,
body_tx: Option<::proto::body::ChunkSender>,
body_rx: Option<Bs>,
is_closing: bool,
}
pub trait Dispatch {
type PollItem;
type PollBody;
type RecvItem;
fn poll_msg(&mut self) -> Poll<Option<(Self::PollItem, Option<Self::PollBody>)>, ::Error>;
fn recv_msg(&mut self, msg: ::Result<(Self::RecvItem, Option<Body>)>) -> ::Result<()>;
fn poll_ready(&mut self) -> Poll<(), ()>;
fn should_poll(&self) -> bool;
}
pub struct Server<S: Service> {
in_flight: Option<S::Future>,
pub(crate) service: S,
}
pub struct Client<B> {
callback: Option<::client::dispatch::Callback<ClientMsg<B>, ::Response>>,
rx: ClientRx<B>,
}
pub type ClientMsg<B> = (RequestHead, Option<B>);
type ClientRx<B> = ::client::dispatch::Receiver<ClientMsg<B>, ::Response>;
impl<D, Bs, I, B, T> Dispatcher<D, Bs, I, B, T>
where
D: Dispatch<PollItem=MessageHead<T::Outgoing>, PollBody=Bs, RecvItem=MessageHead<T::Incoming>>,
I: AsyncRead + AsyncWrite,
B: AsRef<[u8]>,
T: Http1Transaction,
Bs: Stream<Item=B, Error=::Error>,
{
pub fn new(dispatch: D, conn: Conn<I, B, T>) -> Self {
Dispatcher {
conn: conn,
dispatch: dispatch,
body_tx: None,
body_rx: None,
is_closing: false,
}
}
pub fn disable_keep_alive(&mut self) {
self.conn.disable_keep_alive()
}
pub fn into_inner(self) -> (I, Bytes, D) {
let (io, buf) = self.conn.into_inner();
(io, buf, self.dispatch)
}
pub fn poll_until_shutdown(&mut self) -> Poll<(), ::Error> {
self.poll_catch(true)
}
pub fn poll_without_shutdown(&mut self) -> Poll<(), ::Error> {
self.poll_catch(false)
}
fn poll_catch(&mut self, should_shutdown: bool) -> Poll<(), ::Error> {
self.poll_inner(should_shutdown).or_else(|e| {
self.dispatch.recv_msg(Err(e)).map(Async::Ready)
})
}
fn poll_inner(&mut self, should_shutdown: bool) -> Poll<(), ::Error> {
loop {
self.poll_read()?;
self.poll_write()?;
self.poll_flush()?;
if !self.conn.wants_read_again() {
break;
}
}
if self.is_done() {
if should_shutdown {
try_ready!(self.conn.shutdown());
}
self.conn.take_error()?;
Ok(Async::Ready(()))
} else {
Ok(Async::NotReady)
}
}
fn poll_read(&mut self) -> Poll<(), ::Error> {
loop {
if self.is_closing {
return Ok(Async::Ready(()));
} else if self.conn.can_read_head() {
try_ready!(self.poll_read_head());
} else if let Some(mut body) = self.body_tx.take() {
if self.conn.can_read_body() {
match body.poll_ready() {
Ok(Async::Ready(())) => (),
Ok(Async::NotReady) => {
self.body_tx = Some(body);
return Ok(Async::NotReady);
},
Err(_canceled) => {
trace!("body receiver dropped before eof, closing");
self.conn.close_read();
return Ok(Async::Ready(()));
}
}
match self.conn.read_body() {
Ok(Async::Ready(Some(chunk))) => {
match body.start_send(Ok(chunk)) {
Ok(AsyncSink::Ready) => {
self.body_tx = Some(body);
},
Ok(AsyncSink::NotReady(_chunk)) => {
unreachable!("mpsc poll_ready was ready, start_send was not");
}
Err(_canceled) => {
if self.conn.can_read_body() {
trace!("body receiver dropped before eof, closing");
self.conn.close_read();
}
}
}
},
Ok(Async::Ready(None)) => {
},
Ok(Async::NotReady) => {
self.body_tx = Some(body);
return Ok(Async::NotReady);
}
Err(e) => {
let _ = body.start_send(Err(::Error::Io(e)));
}
}
} else {
}
} else {
return self.conn.read_keep_alive().map(Async::Ready);
}
}
}
fn poll_read_head(&mut self) -> Poll<(), ::Error> {
match self.dispatch.poll_ready() {
Ok(Async::Ready(())) => (),
Ok(Async::NotReady) => unreachable!("dispatch not ready when conn is"),
Err(()) => {
trace!("dispatch no longer receiving messages");
self.close();
return Ok(Async::Ready(()));
}
}
match self.conn.read_head() {
Ok(Async::Ready(Some((head, has_body)))) => {
let body = if has_body {
let (mut tx, rx) = ::proto::body::channel();
let _ = tx.poll_ready();
self.body_tx = Some(tx);
Some(rx)
} else {
None
};
self.dispatch.recv_msg(Ok((head, body)))?;
Ok(Async::Ready(()))
},
Ok(Async::Ready(None)) => {
Ok(Async::Ready(()))
}
Ok(Async::NotReady) => Ok(Async::NotReady),
Err(err) => {
debug!("read_head error: {}", err);
self.dispatch.recv_msg(Err(err))?;
Ok(Async::Ready(()))
}
}
}
fn poll_write(&mut self) -> Poll<(), ::Error> {
loop {
if self.is_closing {
return Ok(Async::Ready(()));
} else if self.body_rx.is_none() && self.conn.can_write_head() && self.dispatch.should_poll() {
if let Some((head, body)) = try_ready!(self.dispatch.poll_msg()) {
self.conn.write_head(head, body.is_some());
self.body_rx = body;
} else {
self.close();
return Ok(Async::Ready(()));
}
} else if !self.conn.can_buffer_body() {
try_ready!(self.poll_flush());
} else if let Some(mut body) = self.body_rx.take() {
let chunk = match body.poll()? {
Async::Ready(Some(chunk)) => {
self.body_rx = Some(body);
chunk
},
Async::Ready(None) => {
if self.conn.can_write_body() {
self.conn.write_body(None)?;
}
continue;
},
Async::NotReady => {
self.body_rx = Some(body);
return Ok(Async::NotReady);
}
};
if self.conn.can_write_body() {
assert!(self.conn.write_body(Some(chunk))?.is_ready());
} else if chunk.as_ref().len() == 0 {
} else {
warn!("unexpected chunk when body cannot write");
}
} else {
return Ok(Async::NotReady);
}
}
}
fn poll_flush(&mut self) -> Poll<(), ::Error> {
self.conn.flush().map_err(|err| {
debug!("error writing: {}", err);
err.into()
})
}
fn close(&mut self) {
self.is_closing = true;
self.conn.close_read();
self.conn.close_write();
}
fn is_done(&self) -> bool {
if self.is_closing {
return true;
}
let read_done = self.conn.is_read_closed();
if !T::should_read_first() && read_done {
true
} else {
let write_done = self.conn.is_write_closed() ||
(!self.dispatch.should_poll() && self.body_rx.is_none());
read_done && write_done
}
}
}
impl<D, Bs, I, B, T> Future for Dispatcher<D, Bs, I, B, T>
where
D: Dispatch<PollItem=MessageHead<T::Outgoing>, PollBody=Bs, RecvItem=MessageHead<T::Incoming>>,
I: AsyncRead + AsyncWrite,
B: AsRef<[u8]>,
T: Http1Transaction,
Bs: Stream<Item=B, Error=::Error>,
{
type Item = ();
type Error = ::Error;
#[inline]
fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
self.poll_until_shutdown()
}
}
impl<S> Server<S> where S: Service {
pub fn new(service: S) -> Server<S> {
Server {
in_flight: None,
service: service,
}
}
}
impl<S, Bs> Dispatch for Server<S>
where
S: Service<Request=::Request, Response=::Response<Bs>, Error=::Error>,
Bs: Stream<Error=::Error>,
Bs::Item: AsRef<[u8]>,
{
type PollItem = MessageHead<StatusCode>;
type PollBody = Bs;
type RecvItem = RequestHead;
fn poll_msg(&mut self) -> Poll<Option<(Self::PollItem, Option<Self::PollBody>)>, ::Error> {
if let Some(mut fut) = self.in_flight.take() {
let resp = match fut.poll()? {
Async::Ready(res) => res,
Async::NotReady => {
self.in_flight = Some(fut);
return Ok(Async::NotReady);
}
};
let (head, body) = ::proto::response::split(resp);
Ok(Async::Ready(Some((head.into(), body))))
} else {
unreachable!("poll_msg shouldn't be called if no inflight");
}
}
fn recv_msg(&mut self, msg: ::Result<(Self::RecvItem, Option<Body>)>) -> ::Result<()> {
let (msg, body) = msg?;
let req = ::proto::request::from_wire(None, msg, body);
self.in_flight = Some(self.service.call(req));
Ok(())
}
fn poll_ready(&mut self) -> Poll<(), ()> {
if self.in_flight.is_some() {
Ok(Async::NotReady)
} else {
Ok(Async::Ready(()))
}
}
fn should_poll(&self) -> bool {
self.in_flight.is_some()
}
}
impl<B> Client<B> {
pub fn new(rx: ClientRx<B>) -> Client<B> {
Client {
callback: None,
rx: rx,
}
}
}
impl<B> Dispatch for Client<B>
where
B: Stream<Error=::Error>,
B::Item: AsRef<[u8]>,
{
type PollItem = RequestHead;
type PollBody = B;
type RecvItem = ResponseHead;
fn poll_msg(&mut self) -> Poll<Option<(Self::PollItem, Option<Self::PollBody>)>, ::Error> {
match self.rx.poll() {
Ok(Async::Ready(Some(((head, body), mut cb)))) => {
match cb.poll_cancel().expect("poll_cancel cannot error") {
Async::Ready(()) => {
trace!("request canceled");
Ok(Async::Ready(None))
},
Async::NotReady => {
self.callback = Some(cb);
Ok(Async::Ready(Some((head, body))))
}
}
},
Ok(Async::Ready(None)) => {
trace!("client tx closed");
Ok(Async::Ready(None))
},
Ok(Async::NotReady) => return Ok(Async::NotReady),
Err(_) => unreachable!("receiver cannot error"),
}
}
fn recv_msg(&mut self, msg: ::Result<(Self::RecvItem, Option<Body>)>) -> ::Result<()> {
match msg {
Ok((msg, body)) => {
if let Some(cb) = self.callback.take() {
let res = ::proto::response::from_wire(msg, body);
let _ = cb.send(Ok(res));
Ok(())
} else {
Err(::Error::Io(io::Error::new(io::ErrorKind::InvalidData, "response received without matching request")))
}
},
Err(err) => {
if let Some(cb) = self.callback.take() {
let _ = cb.send(Err((err, None)));
Ok(())
} else if let Ok(Async::Ready(Some((req, cb)))) = self.rx.poll() {
trace!("canceling queued request with connection error: {}", err);
let _ = cb.send(Err((::Error::new_canceled(Some(err)), Some(req))));
Ok(())
} else {
Err(err)
}
}
}
}
fn poll_ready(&mut self) -> Poll<(), ()> {
match self.callback {
Some(ref mut cb) => match cb.poll_cancel() {
Ok(Async::Ready(())) => {
trace!("callback receiver has dropped");
Err(())
},
Ok(Async::NotReady) => Ok(Async::Ready(())),
Err(_) => unreachable!("oneshot poll_cancel cannot error"),
},
None => Err(()),
}
}
fn should_poll(&self) -> bool {
self.callback.is_none()
}
}
#[cfg(test)]
mod tests {
extern crate pretty_env_logger;
use super::*;
use mock::AsyncIo;
use proto::ClientTransaction;
#[test]
fn client_read_bytes_before_writing_request() {
let _ = pretty_env_logger::try_init();
::futures::lazy(|| {
let io = AsyncIo::new_buf(b"HTTP/1.1 200 OK\r\n\r\n".to_vec(), 100);
let (mut tx, rx) = ::client::dispatch::channel();
let conn = Conn::<_, ::Chunk, ClientTransaction>::new(io);
let mut dispatcher = Dispatcher::new(Client::new(rx), conn);
let req = RequestHead {
version: ::HttpVersion::Http11,
subject: ::proto::RequestLine::default(),
headers: Default::default(),
};
let res_rx = tx.try_send((req, None::<::Body>)).unwrap();
let a1 = dispatcher.poll().expect("error should be sent on channel");
assert!(a1.is_ready(), "dispatcher should be closed");
let err = res_rx.wait()
.expect("callback poll")
.expect_err("callback response");
match err {
(::Error::Cancel(_), Some(_)) => (),
other => panic!("expected Canceled, got {:?}", other),
}
Ok::<(), ()>(())
}).wait().unwrap();
}
}