fix(client): properly close idle connections after timeout

Additionally fixes if there were idle connections when a `Client` is
dropped.

Only fixes with the no-proto dispatcher, as changing internals for the
tokio-proto dispatcher would be much harder, and it will replace it very
soon.

Closes #1397

src/client/mod.rs

@@ -249,8 +249,12 @@ where C: Connect,
                     let pool_key = Rc::new(domain.to_string());
                     self.connector.connect(url)
                         .map(move |io| {
-                            let (tx, rx) = mpsc::channel(1);
-                            let pooled = pool.pooled(pool_key, RefCell::new(tx));
+                            let (tx, rx) = mpsc::channel(0);
+                            let tx = HyperClient {
+                                tx: RefCell::new(tx),
+                                should_close: true,
+                            };
+                            let pooled = pool.pooled(pool_key, tx);
                             let conn = proto::Conn::<_, _, proto::ClientTransaction, _>::new(io, pooled.clone());
                             let dispatch = proto::dispatch::Dispatcher::new(proto::dispatch::Client::new(rx), conn);
                             handle.spawn(dispatch.map_err(|err| error!("no_proto error: {}", err)));
@@ -269,9 +273,10 @@ where C: Connect,
                         e.into()
                     });
 
-                let resp = race.and_then(move |client| {
+                let resp = race.and_then(move |mut client| {
                     let (callback, rx) = oneshot::channel();
-                    client.borrow_mut().start_send((head, body, callback)).unwrap();
+                    client.tx.borrow_mut().start_send(proto::dispatch::ClientMsg::Request(head, body, callback)).unwrap();
+                    client.should_close = false;
                     rx.then(|res| {
                         match res {
                             Ok(Ok(res)) => Ok(res),
@@ -309,7 +314,29 @@ impl<C, B> fmt::Debug for Client<C, B> {
 }
 
 type ProtoClient<B> = ClientProxy<Message<RequestHead, B>, Message<proto::ResponseHead, TokioBody>, ::Error>;
-type HyperClient<B> = RefCell<::futures::sync::mpsc::Sender<(RequestHead, Option<B>, ::futures::sync::oneshot::Sender<::Result<::Response>>)>>;
+
+struct HyperClient<B> {
+    tx: RefCell<::futures::sync::mpsc::Sender<proto::dispatch::ClientMsg<B>>>,
+    should_close: bool,
+}
+
+impl<B> Clone for HyperClient<B> {
+    fn clone(&self) -> HyperClient<B> {
+        HyperClient {
+            tx: self.tx.clone(),
+            should_close: self.should_close,
+        }
+    }
+}
+
+impl<B> Drop for HyperClient<B> {
+    fn drop(&mut self) {
+        if self.should_close {
+            self.should_close = false;
+            let _ = self.tx.borrow_mut().try_send(proto::dispatch::ClientMsg::Close);
+        }
+    }
+}
 
 enum Dispatch<B> {
     Proto(Pool<ProtoClient<B>>),

src/proto/conn.rs

@@ -511,6 +511,11 @@ where I: AsyncRead + AsyncWrite,
 
     }
 
+    pub fn close_and_shutdown(&mut self) -> Poll<(), io::Error> {
+        try_ready!(self.flush());
+        self.shutdown()
+    }
+
     pub fn shutdown(&mut self) -> Poll<(), io::Error> {
         match self.io.io_mut().shutdown() {
             Ok(Async::NotReady) => Ok(Async::NotReady),
@@ -625,8 +630,7 @@ where I: AsyncRead + AsyncWrite,
 
     #[inline]
     fn close(&mut self) -> Poll<(), Self::SinkError> {
-        try_ready!(self.poll_complete());
-        self.shutdown()
+        self.close_and_shutdown()
     }
 }
 

src/proto/dispatch.rs

@@ -13,6 +13,7 @@ pub struct Dispatcher<D, Bs, I, B, T, K> {
     dispatch: D,
     body_tx: Option<super::body::BodySender>,
     body_rx: Option<Bs>,
+    is_closing: bool,
 }
 
 pub trait Dispatch {
@@ -34,7 +35,12 @@ pub struct Client<B> {
     rx: ClientRx<B>,
 }
 
-type ClientRx<B> = mpsc::Receiver<(RequestHead, Option<B>, oneshot::Sender<::Result<::Response>>)>;
+pub enum ClientMsg<B> {
+    Request(RequestHead, Option<B>, oneshot::Sender<::Result<::Response>>),
+    Close,
+}
+
+type ClientRx<B> = mpsc::Receiver<ClientMsg<B>>;
 
 impl<D, Bs, I, B, T, K> Dispatcher<D, Bs, I, B, T, K>
 where
@@ -51,6 +57,7 @@ where
             dispatch: dispatch,
             body_tx: None,
             body_rx: None,
+            is_closing: false,
         }
     }
 
@@ -60,7 +67,9 @@ where
 
     fn poll_read(&mut self) -> Poll<(), ::Error> {
         loop {
-            if self.conn.can_read_head() {
+            if self.is_closing {
+                return Ok(Async::Ready(()));
+            } else if self.conn.can_read_head() {
                 match self.conn.read_head() {
                     Ok(Async::Ready(Some((head, has_body)))) => {
                         let body = if has_body {
@@ -149,12 +158,16 @@ where
 
     fn poll_write(&mut self) -> Poll<(), ::Error> {
         loop {
-            if self.body_rx.is_none() && self.dispatch.should_poll() {
+            if self.is_closing {
+                return Ok(Async::Ready(()));
+            } else if self.body_rx.is_none() && 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.conn.close_write();
+                    self.is_closing = true;
+                    //self.conn.close_read();
+                    //self.conn.close_write();
                     return Ok(Async::Ready(()));
                 }
             } else if self.conn.has_queued_body() {
@@ -190,6 +203,16 @@ where
         })
     }
 
+    fn poll_close(&mut self) -> Poll<(), ::Error> {
+        debug_assert!(self.is_closing);
+
+        try_ready!(self.conn.close_and_shutdown());
+        self.conn.close_read();
+        self.conn.close_write();
+        self.is_closing = false;
+        Ok(Async::Ready(()))
+    }
+
     fn is_done(&self) -> bool {
         let read_done = self.conn.is_read_closed();
 
@@ -224,6 +247,10 @@ where
         self.poll_write()?;
         self.poll_flush()?;
 
+        if self.is_closing {
+            self.poll_close()?;
+        }
+
         if self.is_done() {
             try_ready!(self.conn.shutdown());
             trace!("Dispatch::poll done");
@@ -285,6 +312,7 @@ where
 
 // ===== impl Client =====
 
+
 impl<B> Client<B> {
     pub fn new(rx: ClientRx<B>) -> Client<B> {
         Client {
@@ -305,11 +333,13 @@ where
 
     fn poll_msg(&mut self) -> Poll<Option<(Self::PollItem, Option<Self::PollBody>)>, ::Error> {
         match self.rx.poll() {
-            Ok(Async::Ready(Some((head, body, cb)))) => {
+            Ok(Async::Ready(Some(ClientMsg::Request(head, body, cb)))) => {
                 self.callback = Some(cb);
                 Ok(Async::Ready(Some((head, body))))
             },
+            Ok(Async::Ready(Some(ClientMsg::Close))) |
             Ok(Async::Ready(None)) => {
+                trace!("client tx closed");
                 // user has dropped sender handle
                 Ok(Async::Ready(None))
             },

tests/client.rs

@@ -607,7 +607,7 @@ mod dispatch_impl {
     }
 
     #[test]
-    fn drop_client_closes_connection() {
+    fn dropped_client_closes_connection() {
         // https://github.com/hyperium/hyper/issues/1353
         let _ = pretty_env_logger::init();
 
@@ -653,6 +653,57 @@ mod dispatch_impl {
         assert_eq!(closes.load(Ordering::Relaxed), 1);
     }
 
+
+    #[test]
+    fn drop_client_closes_idle_connections() {
+        let _ = pretty_env_logger::init();
+
+        let server = TcpListener::bind("127.0.0.1:0").unwrap();
+        let addr = server.local_addr().unwrap();
+        let mut core = Core::new().unwrap();
+        let handle = core.handle();
+        let closes = Arc::new(AtomicUsize::new(0));
+
+        let (tx1, rx1) = oneshot::channel();
+        let (_client_drop_tx, client_drop_rx) = oneshot::channel::<()>();
+
+        thread::spawn(move || {
+            let mut sock = server.accept().unwrap().0;
+            sock.set_read_timeout(Some(Duration::from_secs(5))).unwrap();
+            sock.set_write_timeout(Some(Duration::from_secs(5))).unwrap();
+            let mut buf = [0; 4096];
+            sock.read(&mut buf).expect("read 1");
+            let body =[b'x'; 64];
+            write!(sock, "HTTP/1.1 200 OK\r\nContent-Length: {}\r\n\r\n", body.len()).expect("write head");
+            let _ = sock.write_all(&body);
+            let _ = tx1.send(());
+
+            // prevent this thread from closing until end of test, so the connection
+            // stays open and idle until Client is dropped
+            let _ = client_drop_rx.wait();
+        });
+
+        let uri = format!("http://{}/a", addr).parse().unwrap();
+
+        let client = Client::configure()
+            .connector(DebugConnector(HttpConnector::new(1, &handle), closes.clone()))
+            .no_proto()
+            .build(&handle);
+        let res = client.get(uri).and_then(move |res| {
+            assert_eq!(res.status(), hyper::StatusCode::Ok);
+            res.body().concat2()
+        });
+        let rx = rx1.map_err(|_| hyper::Error::Io(io::Error::new(io::ErrorKind::Other, "thread panicked")));
+        core.run(res.join(rx).map(|r| r.0)).unwrap();
+
+        // not closed yet, just idle
+        assert_eq!(closes.load(Ordering::Relaxed), 0);
+        drop(client);
+        core.run(Timeout::new(Duration::from_millis(100), &handle).unwrap()).unwrap();
+
+        assert_eq!(closes.load(Ordering::Relaxed), 1);
+    }
+
     #[test]
     fn no_keep_alive_closes_connection() {
         // https://github.com/hyperium/hyper/issues/1383