Fix back-pressure handling for concurrent connections

CHANGES.md

@@ -1,5 +1,34 @@
 # Changes
 
+## [0.2.6] - 2018-12-21
+
+### Fixed
+
+* Fix back-pressure handling for concurrent connections
+
+
+## [0.2.5] - 2018-12-12
+
+### Fixed
+
+* Fix back-pressure for concurrent ssl handshakes
+
+* Drop completed future for .then and .and_then combinators
+
+
+## [0.2.4] - 2018-11-21
+
+### Added
+
+* Allow to skip name resolution stage in Connector
+
+
+## [0.2.3] - 2018-11-17
+
+### Added
+
+* Framed::is_write_buf_empty() checks if write buffer is flushed
+
 ## [0.2.2] - 2018-11-14
 
 ### Added

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "actix-net"
-version = "0.2.2"
+version = "0.2.6"
 authors = ["Nikolay Kim <fafhrd91@gmail.com>"]
 description = "Actix net - framework for the compisible network services for Rust (experimental)"
 readme = "README.md"
@@ -58,8 +58,7 @@ tokio-timer = "0.2"
 tokio-reactor = "0.1"
 tokio-current-thread = "0.1"
 tower-service = "0.1"
-trust-dns-proto = "^0.5.0"
-trust-dns-resolver = "^0.10.0"
+trust-dns-resolver = "^0.10.2"
 
 # native-tls
 native-tls = { version="0.2", optional = true }

examples/basic.rs

@@ -80,7 +80,8 @@ fn main() {
                     future::ok(())
                 })
             },
-        ).unwrap()
+        )
+        .unwrap()
         .start();
 
     sys.run();

examples/ssl.rs

@@ -61,7 +61,8 @@ fn main() {
                     println!("got ssl connection {:?}", num);
                     future::ok(())
                 })
-        }).unwrap()
+        })
+        .unwrap()
         .start();
 
     sys.run();

src/codec/framed.rs

@@ -135,6 +135,11 @@ impl<T, U> Framed<T, U> {
         &mut self.inner.get_mut().get_mut().0
     }
 
+    /// Check if write buffer is empty.
+    pub fn is_write_buf_empty(&self) -> bool {
+        self.inner.get_ref().is_empty()
+    }
+
     /// Check if write buffer is full.
     pub fn is_write_buf_full(&self) -> bool {
         self.inner.get_ref().is_full()

src/codec/framed_write.rs

@@ -77,6 +77,11 @@ impl<T, E> FramedWrite<T, E> {
     pub fn is_full(&self) -> bool {
         self.inner.is_full()
     }
+
+    /// Check if write buffer is empty.
+    pub fn is_empty(&self) -> bool {
+        self.inner.is_empty()
+    }
 }
 
 impl<T, E> FramedWrite<T, E>
@@ -194,6 +199,10 @@ impl<T> FramedWrite2<T> {
     pub fn is_full(&self) -> bool {
         self.buffer.len() >= self.high_watermark
     }
+
+    pub fn is_empty(&self) -> bool {
+        self.buffer.is_empty()
+    }
 }
 
 impl<T> FramedWrite2<T>
@@ -245,7 +254,8 @@ where
                     io::ErrorKind::WriteZero,
                     "failed to \
                      write frame to transport",
-                ).into());
+                )
+                .into());
             }
 
             // TODO: Add a way to `bytes` to do this w/o returning the drained

src/connector.rs

@@ -4,10 +4,9 @@ use std::net::{IpAddr, SocketAddr};
 use std::time::Duration;
 use std::{fmt, io};
 
-use futures::{
-    future::{ok, FutureResult},
-    Async, Future, Poll,
-};
+use futures::future::{ok, Either, FutureResult};
+use futures::{Async, Future, Poll};
+
 use tokio_tcp::{ConnectFuture, TcpStream};
 use trust_dns_resolver::config::{ResolverConfig, ResolverOpts};
 use trust_dns_resolver::system_conf::read_system_conf;
@@ -58,17 +57,24 @@ impl From<io::Error> for ConnectorError {
 /// Connect request
 #[derive(Eq, PartialEq, Debug, Hash)]
 pub struct Connect {
-    pub host: String,
-    pub port: u16,
+    pub kind: ConnectKind,
     pub timeout: Duration,
 }
 
+#[derive(Eq, PartialEq, Debug, Hash)]
+pub enum ConnectKind {
+    Host { host: String, port: u16 },
+    Addr { host: String, addr: SocketAddr },
+}
+
 impl Connect {
     /// Create new `Connect` instance.
     pub fn new<T: AsRef<str>>(host: T, port: u16) -> Connect {
         Connect {
-            port,
-            host: host.as_ref().to_owned(),
+            kind: ConnectKind::Host {
+                host: host.as_ref().to_owned(),
+                port,
+            },
             timeout: Duration::from_secs(1),
         }
     }
@@ -82,12 +88,25 @@ impl Connect {
             .parse::<u16>()
             .map_err(|_| ConnectorError::InvalidInput)?;
         Ok(Connect {
-            port,
-            host: host.to_owned(),
+            kind: ConnectKind::Host {
+                host: host.to_owned(),
+                port,
+            },
             timeout: Duration::from_secs(1),
         })
     }
 
+    /// Create new `Connect` instance from host and address. Connector skips name resolution stage for such connect messages.
+    pub fn with_address<T: Into<String>>(host: T, addr: SocketAddr) -> Connect {
+        Connect {
+            kind: ConnectKind::Addr {
+                addr,
+                host: host.into(),
+            },
+            timeout: Duration::from_secs(1),
+        }
+    }
+
     /// Set connect timeout
     ///
     /// By default timeout is set to a 1 second.
@@ -99,19 +118,25 @@ impl Connect {
 
 impl RequestHost for Connect {
     fn host(&self) -> &str {
-        &self.host
+        match self.kind {
+            ConnectKind::Host { ref host, port: _ } => host,
+            ConnectKind::Addr { ref host, addr: _ } => host,
+        }
     }
 }
 
 impl RequestPort for Connect {
     fn port(&self) -> u16 {
-        self.port
+        match self.kind {
+            ConnectKind::Host { host: _, port } => port,
+            ConnectKind::Addr { host: _, addr } => addr.port(),
+        }
     }
 }
 
 impl fmt::Display for Connect {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "{}:{}", self.host, self.port)
+        write!(f, "{}:{}", self.host(), self.port())
     }
 }
 
@@ -174,16 +199,25 @@ impl Service for Connector {
     type Request = Connect;
     type Response = (Connect, TcpStream);
     type Error = ConnectorError;
-    type Future = ConnectorFuture;
+    type Future = Either<ConnectorFuture, ConnectorTcpFuture>;
 
     fn poll_ready(&mut self) -> Poll<(), Self::Error> {
         Ok(Async::Ready(()))
     }
 
     fn call(&mut self, req: Self::Request) -> Self::Future {
-        ConnectorFuture {
-            fut: self.resolver.call(req),
-            fut2: None,
+        match req.kind {
+            ConnectKind::Host { host: _, port: _ } => Either::A(ConnectorFuture {
+                fut: self.resolver.call(req),
+                fut2: None,
+            }),
+            ConnectKind::Addr { host: _, addr } => {
+                let mut addrs = VecDeque::new();
+                addrs.push_back(addr.ip());
+                Either::B(ConnectorTcpFuture {
+                    fut: TcpConnectorResponse::new(req, addrs),
+                })
+            }
         }
     }
 }
@@ -216,6 +250,20 @@ impl Future for ConnectorFuture {
     }
 }
 
+#[doc(hidden)]
+pub struct ConnectorTcpFuture {
+    fut: TcpConnectorResponse<Connect>,
+}
+
+impl Future for ConnectorTcpFuture {
+    type Item = (Connect, TcpStream);
+    type Error = ConnectorError;
+
+    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+        self.fut.poll().map_err(ConnectorError::IoError)
+    }
+}
+
 /// Tcp stream connector service
 pub struct TcpConnector<T: RequestPort>(PhantomData<T>);
 
@@ -325,7 +373,7 @@ impl Service for DefaultConnector {
 
 #[doc(hidden)]
 pub struct DefaultConnectorFuture {
-    fut: ConnectorFuture,
+    fut: Either<ConnectorFuture, ConnectorTcpFuture>,
 }
 
 impl Future for DefaultConnectorFuture {

src/counter.rs

@@ -9,6 +9,7 @@ use futures::task::AtomicTask;
 /// Counter could be cloned, total ncount is shared across all clones.
 pub struct Counter(Rc<CounterInner>);
 
+#[derive(Debug)]
 struct CounterInner {
     count: Cell<usize>,
     capacity: usize,
@@ -40,6 +41,7 @@ impl Counter {
     }
 }
 
+#[derive(Debug)]
 pub struct CounterGuard(Rc<CounterInner>);
 
 impl CounterGuard {
@@ -57,11 +59,7 @@ impl Drop for CounterGuard {
 
 impl CounterInner {
     fn inc(&self) {
-        let num = self.count.get() + 1;
-        self.count.set(num);
-        if num == self.capacity {
-            self.task.register();
-        }
+        self.count.set(self.count.get() + 1);
     }
 
     fn dec(&self) {
@@ -73,6 +71,10 @@ impl CounterInner {
     }
 
     fn available(&self) -> bool {
-        self.count.get() < self.capacity
+        let avail = self.count.get() < self.capacity;
+        if !avail {
+            self.task.register();
+        }
+        avail
     }
 }

src/lib.rs

@@ -9,10 +9,7 @@
 
 #![cfg_attr(
     feature = "cargo-clippy",
-    allow(
-        declare_interior_mutable_const,
-        borrow_interior_mutable_const
-    )
+    allow(declare_interior_mutable_const, borrow_interior_mutable_const)
 )]
 
 #[macro_use]

src/server/services.rs

@@ -83,9 +83,9 @@ where
                 });
 
                 if let Ok(stream) = stream {
-                    spawn(self.service.call(stream).map_err(|_| ()).map(move |val| {
+                    spawn(self.service.call(stream).then(move |res| {
                         drop(guard);
-                        val
+                        res.map_err(|_| ())
                     }));
                     ok(())
                 } else {
@@ -123,9 +123,9 @@ where
     }
 
     fn call(&mut self, (guard, req): (Option<CounterGuard>, ServerMessage)) -> Self::Future {
-        spawn(self.service.call(req).map_err(|_| ()).map(move |val| {
+        spawn(self.service.call(req).then(move |res| {
             drop(guard);
-            val
+            res.map_err(|_| ())
         }));
         ok(())
     }

src/server/worker.rs

@@ -167,7 +167,8 @@ impl Worker {
                 .map_err(|e| {
                     error!("Can not start worker: {:?}", e);
                     Arbiter::current().do_send(StopArbiter(0));
-                }).and_then(move |services| {
+                })
+                .and_then(move |services| {
                     for item in services {
                         for (idx, token, service) in item {
                             while token.0 >= wrk.services.len() {

src/service/and_then.rs

@@ -63,7 +63,7 @@ where
 {
     b: Cell<B>,
     fut_b: Option<B::Future>,
-    fut_a: A::Future,
+    fut_a: Option<A::Future>,
 }
 
 impl<A, B> AndThenFuture<A, B>
@@ -71,10 +71,10 @@ where
     A: Service,
     B: Service<Request = A::Response, Error = A::Error>,
 {
-    fn new(fut_a: A::Future, b: Cell<B>) -> Self {
+    fn new(a: A::Future, b: Cell<B>) -> Self {
         AndThenFuture {
             b,
-            fut_a,
+            fut_a: Some(a),
             fut_b: None,
         }
     }
@@ -94,8 +94,9 @@ where
             return fut.poll();
         }
 
-        match self.fut_a.poll() {
+        match self.fut_a.as_mut().expect("actix-net bug").poll() {
             Ok(Async::Ready(resp)) => {
+                let _ = self.fut_a.take();
                 self.fut_b = Some(self.b.borrow_mut().call(resp));
                 self.poll()
             }

src/service/then.rs

@@ -63,7 +63,7 @@ where
 {
     b: Cell<B>,
     fut_b: Option<B::Future>,
-    fut_a: A::Future,
+    fut_a: Option<A::Future>,
 }
 
 impl<A, B> ThenFuture<A, B>
@@ -71,10 +71,10 @@ where
     A: Service,
     B: Service<Request = Result<A::Response, A::Error>>,
 {
-    fn new(fut_a: A::Future, b: Cell<B>) -> Self {
+    fn new(a: A::Future, b: Cell<B>) -> Self {
         ThenFuture {
             b,
-            fut_a,
+            fut_a: Some(a),
             fut_b: None,
         }
     }
@@ -93,12 +93,14 @@ where
             return fut.poll();
         }
 
-        match self.fut_a.poll() {
+        match self.fut_a.as_mut().expect("actix-net bug").poll() {
             Ok(Async::Ready(resp)) => {
+                let _ = self.fut_a.take();
                 self.fut_b = Some(self.b.borrow_mut().call(Ok(resp)));
                 self.poll()
             }
             Err(err) => {
+                let _ = self.fut_a.take();
                 self.fut_b = Some(self.b.borrow_mut().call(Err(err)));
                 self.poll()
             }