add http client connector service

Cargo.toml

@@ -34,16 +34,26 @@ session = ["cookie/secure"]
 
 cell = ["actix-net/cell"]
 
+# tls
+tls = ["native-tls", "actix-net/tls"]
+
+# openssl
+ssl = ["openssl", "actix-net/ssl"]
+
+# rustls
+rust-tls = ["rustls", "actix-net/rust-tls"]
+
 [dependencies]
 actix = "0.7.5"
-actix-net = "0.2.0"
-#actix-net = { git="https://github.com/actix/actix-net.git" }
+#actix-net = "0.2.0"
+actix-net = { git="https://github.com/actix/actix-net.git" }
 
 base64 = "0.9"
 bitflags = "1.0"
 http = "0.1.8"
 httparse = "1.3"
 failure = "0.1.2"
+indexmap = "1.0"
 log = "0.4"
 mime = "0.3"
 rand = "0.5"
@@ -61,6 +71,7 @@ url = { version="1.7", features=["query_encoding"] }
 
 # io
 net2 = "0.2"
+slab = "0.4"
 bytes = "0.4"
 byteorder = "1.2"
 futures = "0.1"
@@ -70,6 +81,17 @@ tokio-io = "0.1"
 tokio-tcp = "0.1"
 tokio-timer = "0.2"
 tokio-current-thread = "0.1"
+trust-dns-proto = "0.5.0"
+trust-dns-resolver = "0.10.0"
+
+# native-tls
+native-tls = { version="0.2", optional = true }
+
+# openssl
+openssl = { version="0.10", optional = true }
+
+#rustls
+rustls = { version = "^0.14", optional = true }
 
 [dev-dependencies]
 actix-web = "0.7"

src/client/connect.rs

@@ -0,0 +1,80 @@
+use actix_net::connector::RequestPort;
+use actix_net::resolver::RequestHost;
+use http::uri::Uri;
+use http::{Error as HttpError, HttpTryFrom};
+
+use super::error::{ConnectorError, InvalidUrlKind};
+use super::pool::Key;
+
+#[derive(Debug)]
+/// `Connect` type represents a message that can be sent to
+/// `Connector` with a connection request.
+pub struct Connect {
+    pub(crate) uri: Uri,
+}
+
+impl Connect {
+    /// Construct `Uri` instance and create `Connect` message.
+    pub fn new<U>(uri: U) -> Result<Connect, HttpError>
+    where
+        Uri: HttpTryFrom<U>,
+    {
+        Ok(Connect {
+            uri: Uri::try_from(uri).map_err(|e| e.into())?,
+        })
+    }
+
+    /// Create `Connect` message for specified `Uri`
+    pub fn with(uri: Uri) -> Connect {
+        Connect { uri }
+    }
+
+    pub(crate) fn is_secure(&self) -> bool {
+        if let Some(scheme) = self.uri.scheme_part() {
+            scheme.as_str() == "https"
+        } else {
+            false
+        }
+    }
+
+    pub(crate) fn key(&self) -> Key {
+        self.uri.authority_part().unwrap().clone().into()
+    }
+
+    pub(crate) fn validate(&self) -> Result<(), ConnectorError> {
+        if self.uri.host().is_none() {
+            Err(ConnectorError::InvalidUrl(InvalidUrlKind::MissingHost))
+        } else if self.uri.scheme_part().is_none() {
+            Err(ConnectorError::InvalidUrl(InvalidUrlKind::MissingScheme))
+        } else if let Some(scheme) = self.uri.scheme_part() {
+            match scheme.as_str() {
+                "http" | "ws" | "https" | "wss" => Ok(()),
+                _ => Err(ConnectorError::InvalidUrl(InvalidUrlKind::UnknownScheme)),
+            }
+        } else {
+            Ok(())
+        }
+    }
+}
+
+impl RequestHost for Connect {
+    fn host(&self) -> &str {
+        &self.uri.host().unwrap()
+    }
+}
+
+impl RequestPort for Connect {
+    fn port(&self) -> u16 {
+        if let Some(port) = self.uri.port() {
+            port
+        } else if let Some(scheme) = self.uri.scheme_part() {
+            match scheme.as_str() {
+                "http" | "ws" => 80,
+                "https" | "wss" => 443,
+                _ => 80,
+            }
+        } else {
+            80
+        }
+    }
+}

src/client/connection.rs

@@ -0,0 +1,79 @@
+use std::{fmt, io, time};
+
+use futures::Poll;
+use tokio_io::{AsyncRead, AsyncWrite};
+
+use super::pool::Acquired;
+
+/// HTTP client connection
+pub struct Connection<T: AsyncRead + AsyncWrite + 'static> {
+    io: T,
+    created: time::Instant,
+    pool: Option<Acquired<T>>,
+}
+
+impl<T> fmt::Debug for Connection<T>
+where
+    T: AsyncRead + AsyncWrite + fmt::Debug + 'static,
+{
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "Connection {:?}", self.io)
+    }
+}
+
+impl<T: AsyncRead + AsyncWrite + 'static> Connection<T> {
+    pub(crate) fn new(io: T, created: time::Instant, pool: Acquired<T>) -> Self {
+        Connection {
+            io,
+            created,
+            pool: Some(pool),
+        }
+    }
+
+    /// Raw IO stream
+    pub fn get_mut(&mut self) -> &mut T {
+        &mut self.io
+    }
+
+    /// Close connection
+    pub fn close(mut self) {
+        if let Some(mut pool) = self.pool.take() {
+            pool.close(self)
+        }
+    }
+
+    /// Release this connection to the connection pool
+    pub fn release(mut self) {
+        if let Some(mut pool) = self.pool.take() {
+            pool.release(self)
+        }
+    }
+
+    pub(crate) fn into_inner(self) -> (T, time::Instant) {
+        (self.io, self.created)
+    }
+}
+
+impl<T: AsyncRead + AsyncWrite + 'static> io::Read for Connection<T> {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        self.io.read(buf)
+    }
+}
+
+impl<T: AsyncRead + AsyncWrite + 'static> AsyncRead for Connection<T> {}
+
+impl<T: AsyncRead + AsyncWrite + 'static> io::Write for Connection<T> {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        self.io.write(buf)
+    }
+
+    fn flush(&mut self) -> io::Result<()> {
+        self.io.flush()
+    }
+}
+
+impl<T: AsyncRead + AsyncWrite + 'static> AsyncWrite for Connection<T> {
+    fn shutdown(&mut self) -> Poll<(), io::Error> {
+        self.io.shutdown()
+    }
+}

src/client/connector.rs

@@ -0,0 +1,500 @@
+use std::time::Duration;
+use std::{fmt, io};
+
+use actix_net::connector::TcpConnector;
+use actix_net::resolver::Resolver;
+use actix_net::service::{Service, ServiceExt};
+use actix_net::timeout::{TimeoutError, TimeoutService};
+use futures::future::Either;
+use futures::Poll;
+use tokio_io::{AsyncRead, AsyncWrite};
+use trust_dns_resolver::config::{ResolverConfig, ResolverOpts};
+
+use super::connect::Connect;
+use super::connection::Connection;
+use super::error::ConnectorError;
+use super::pool::ConnectionPool;
+
+#[cfg(feature = "ssl")]
+use actix_net::ssl::OpensslConnector;
+#[cfg(feature = "ssl")]
+use openssl::ssl::{SslConnector, SslMethod};
+
+#[cfg(not(feature = "ssl"))]
+type SslConnector = ();
+
+/// Http client connector builde instance.
+/// `Connector` type uses builder-like pattern for connector service construction.
+pub struct Connector {
+    resolver: Resolver<Connect>,
+    timeout: Duration,
+    conn_lifetime: Duration,
+    conn_keep_alive: Duration,
+    disconnect_timeout: Duration,
+    limit: usize,
+    #[allow(dead_code)]
+    connector: SslConnector,
+}
+
+impl Default for Connector {
+    fn default() -> Connector {
+        let connector = {
+            #[cfg(feature = "ssl")]
+            {
+                SslConnector::builder(SslMethod::tls()).unwrap().build()
+            }
+            #[cfg(not(feature = "ssl"))]
+            {
+                ()
+            }
+        };
+
+        Connector {
+            connector,
+            resolver: Resolver::default(),
+            timeout: Duration::from_secs(1),
+            conn_lifetime: Duration::from_secs(75),
+            conn_keep_alive: Duration::from_secs(15),
+            disconnect_timeout: Duration::from_millis(3000),
+            limit: 100,
+        }
+    }
+}
+
+impl Connector {
+    /// Use custom resolver configuration.
+    pub fn resolver_config(mut self, cfg: ResolverConfig, opts: ResolverOpts) -> Self {
+        self.resolver = Resolver::new(cfg, opts);
+        self
+    }
+
+    /// Connection timeout, i.e. max time to connect to remote host including dns name resolution.
+    /// Set to 1 second by default.
+    pub fn timeout(mut self, timeout: Duration) -> Self {
+        self.timeout = timeout;
+        self
+    }
+
+    #[cfg(feature = "ssl")]
+    /// Use custom `SslConnector` instance.
+    pub fn ssl(mut self, connector: SslConnector) -> Self {
+        self.connector = connector;
+        self
+    }
+
+    /// Set total number of simultaneous connections per type of scheme.
+    ///
+    /// If limit is 0, the connector has no limit.
+    /// The default limit size is 100.
+    pub fn limit(mut self, limit: usize) -> Self {
+        self.limit = limit;
+        self
+    }
+
+    /// Set keep-alive period for opened connection.
+    ///
+    /// Keep-alive period is the period between connection usage. If
+    /// the delay between repeated usages of the same connection
+    /// exceeds this period, the connection is closed.
+    /// Default keep-alive period is 15 seconds.
+    pub fn conn_keep_alive(mut self, dur: Duration) -> Self {
+        self.conn_keep_alive = dur;
+        self
+    }
+
+    /// Set max lifetime period for connection.
+    ///
+    /// Connection lifetime is max lifetime of any opened connection
+    /// until it is closed regardless of keep-alive period.
+    /// Default lifetime period is 75 seconds.
+    pub fn conn_lifetime(mut self, dur: Duration) -> Self {
+        self.conn_lifetime = dur;
+        self
+    }
+
+    /// Set server connection disconnect timeout in milliseconds.
+    ///
+    /// Defines a timeout for disconnect connection. If a disconnect procedure does not complete
+    /// within this time, the socket get dropped. This timeout affects only secure connections.
+    ///
+    /// To disable timeout set value to 0.
+    ///
+    /// By default disconnect timeout is set to 3000 milliseconds.
+    pub fn disconnect_timeout(mut self, dur: Duration) -> Self {
+        self.disconnect_timeout = dur;
+        self
+    }
+
+    /// Finish configuration process and create connector service.
+    pub fn service(
+        self,
+    ) -> impl Service<
+        Request = Connect,
+        Response = impl AsyncRead + AsyncWrite + fmt::Debug,
+        Error = ConnectorError,
+    > + Clone {
+        #[cfg(not(feature = "ssl"))]
+        {
+            let connector = TimeoutService::new(
+                self.timeout,
+                self.resolver
+                    .map_err(ConnectorError::from)
+                    .and_then(TcpConnector::default().from_err()),
+            ).map_err(|e| match e {
+                TimeoutError::Service(e) => e,
+                TimeoutError::Timeout => ConnectorError::Timeout,
+            });
+
+            connect_impl::InnerConnector {
+                tcp_pool: ConnectionPool::new(
+                    connector,
+                    self.conn_lifetime,
+                    self.conn_keep_alive,
+                    None,
+                    self.limit,
+                ),
+            }
+        }
+        #[cfg(feature = "ssl")]
+        {
+            let ssl_service = TimeoutService::new(
+                self.timeout,
+                self.resolver
+                    .clone()
+                    .map_err(ConnectorError::from)
+                    .and_then(TcpConnector::default().from_err())
+                    .and_then(
+                        OpensslConnector::service(self.connector)
+                            .map_err(ConnectorError::SslError),
+                    ),
+            ).map_err(|e| match e {
+                TimeoutError::Service(e) => e,
+                TimeoutError::Timeout => ConnectorError::Timeout,
+            });
+
+            let tcp_service = TimeoutService::new(
+                self.timeout,
+                self.resolver
+                    .map_err(ConnectorError::from)
+                    .and_then(TcpConnector::default().from_err()),
+            ).map_err(|e| match e {
+                TimeoutError::Service(e) => e,
+                TimeoutError::Timeout => ConnectorError::Timeout,
+            });
+
+            connect_impl::InnerConnector {
+                tcp_pool: ConnectionPool::new(
+                    tcp_service,
+                    self.conn_lifetime,
+                    self.conn_keep_alive,
+                    None,
+                    self.limit,
+                ),
+                ssl_pool: ConnectionPool::new(
+                    ssl_service,
+                    self.conn_lifetime,
+                    self.conn_keep_alive,
+                    Some(self.disconnect_timeout),
+                    self.limit,
+                ),
+            }
+        }
+    }
+}
+
+#[cfg(not(feature = "ssl"))]
+mod connect_impl {
+    use super::*;
+    use futures::future::{err, FutureResult};
+
+    pub(crate) struct InnerConnector<T, Io>
+    where
+        Io: AsyncRead + AsyncWrite + 'static,
+        T: Service<Request = Connect, Response = (Connect, Io), Error = ConnectorError>,
+    {
+        pub(crate) tcp_pool: ConnectionPool<T, Io>,
+    }
+
+    impl<T, Io> Clone for InnerConnector<T, Io>
+    where
+        Io: AsyncRead + AsyncWrite + 'static,
+        T: Service<Request = Connect, Response = (Connect, Io), Error = ConnectorError>
+            + Clone,
+    {
+        fn clone(&self) -> Self {
+            InnerConnector {
+                tcp_pool: self.tcp_pool.clone(),
+            }
+        }
+    }
+
+    impl<T, Io> Service for InnerConnector<T, Io>
+    where
+        Io: AsyncRead + AsyncWrite + 'static,
+        T: Service<Request = Connect, Response = (Connect, Io), Error = ConnectorError>,
+    {
+        type Request = Connect;
+        type Response = Connection<Io>;
+        type Error = ConnectorError;
+        type Future = Either<
+            <ConnectionPool<T, Io> as Service>::Future,
+            FutureResult<Connection<Io>, ConnectorError>,
+        >;
+
+        fn poll_ready(&mut self) -> Poll<(), Self::Error> {
+            self.tcp_pool.poll_ready()
+        }
+
+        fn call(&mut self, req: Self::Request) -> Self::Future {
+            if req.is_secure() {
+                Either::B(err(ConnectorError::SslIsNotSupported))
+            } else if let Err(e) = req.validate() {
+                Either::B(err(e))
+            } else {
+                Either::A(self.tcp_pool.call(req))
+            }
+        }
+    }
+}
+
+#[cfg(feature = "ssl")]
+mod connect_impl {
+    use std::marker::PhantomData;
+
+    use futures::future::{err, FutureResult};
+    use futures::{Async, Future, Poll};
+
+    use super::*;
+
+    pub(crate) struct InnerConnector<T1, T2, Io1, Io2>
+    where
+        Io1: AsyncRead + AsyncWrite + 'static,
+        Io2: AsyncRead + AsyncWrite + 'static,
+        T1: Service<
+            Request = Connect,
+            Response = (Connect, Io1),
+            Error = ConnectorError,
+        >,
+        T2: Service<
+            Request = Connect,
+            Response = (Connect, Io2),
+            Error = ConnectorError,
+        >,
+    {
+        pub(crate) tcp_pool: ConnectionPool<T1, Io1>,
+        pub(crate) ssl_pool: ConnectionPool<T2, Io2>,
+    }
+
+    impl<T1, T2, Io1, Io2> Clone for InnerConnector<T1, T2, Io1, Io2>
+    where
+        Io1: AsyncRead + AsyncWrite + 'static,
+        Io2: AsyncRead + AsyncWrite + 'static,
+        T1: Service<
+                Request = Connect,
+                Response = (Connect, Io1),
+                Error = ConnectorError,
+            > + Clone,
+        T2: Service<
+                Request = Connect,
+                Response = (Connect, Io2),
+                Error = ConnectorError,
+            > + Clone,
+    {
+        fn clone(&self) -> Self {
+            InnerConnector {
+                tcp_pool: self.tcp_pool.clone(),
+                ssl_pool: self.ssl_pool.clone(),
+            }
+        }
+    }
+
+    impl<T1, T2, Io1, Io2> Service for InnerConnector<T1, T2, Io1, Io2>
+    where
+        Io1: AsyncRead + AsyncWrite + 'static,
+        Io2: AsyncRead + AsyncWrite + 'static,
+        T1: Service<
+            Request = Connect,
+            Response = (Connect, Io1),
+            Error = ConnectorError,
+        >,
+        T2: Service<
+            Request = Connect,
+            Response = (Connect, Io2),
+            Error = ConnectorError,
+        >,
+    {
+        type Request = Connect;
+        type Response = IoEither<Connection<Io1>, Connection<Io2>>;
+        type Error = ConnectorError;
+        type Future = Either<
+            FutureResult<Self::Response, Self::Error>,
+            Either<
+                InnerConnectorResponseA<T1, Io1, Io2>,
+                InnerConnectorResponseB<T2, Io1, Io2>,
+            >,
+        >;
+
+        fn poll_ready(&mut self) -> Poll<(), Self::Error> {
+            self.tcp_pool.poll_ready()
+        }
+
+        fn call(&mut self, req: Self::Request) -> Self::Future {
+            if let Err(e) = req.validate() {
+                Either::A(err(e))
+            } else if req.is_secure() {
+                Either::B(Either::A(InnerConnectorResponseA {
+                    fut: self.tcp_pool.call(req),
+                    _t: PhantomData,
+                }))
+            } else {
+                Either::B(Either::B(InnerConnectorResponseB {
+                    fut: self.ssl_pool.call(req),
+                    _t: PhantomData,
+                }))
+            }
+        }
+    }
+
+    pub(crate) struct InnerConnectorResponseA<T, Io1, Io2>
+    where
+        Io1: AsyncRead + AsyncWrite + 'static,
+        T: Service<Request = Connect, Response = (Connect, Io1), Error = ConnectorError>,
+    {
+        fut: <ConnectionPool<T, Io1> as Service>::Future,
+        _t: PhantomData<Io2>,
+    }
+
+    impl<T, Io1, Io2> Future for InnerConnectorResponseA<T, Io1, Io2>
+    where
+        T: Service<Request = Connect, Response = (Connect, Io1), Error = ConnectorError>,
+        Io1: AsyncRead + AsyncWrite + 'static,
+        Io2: AsyncRead + AsyncWrite + 'static,
+    {
+        type Item = IoEither<Connection<Io1>, Connection<Io2>>;
+        type Error = ConnectorError;
+
+        fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+            match self.fut.poll()? {
+                Async::NotReady => Ok(Async::NotReady),
+                Async::Ready(res) => Ok(Async::Ready(IoEither::A(res))),
+            }
+        }
+    }
+
+    pub(crate) struct InnerConnectorResponseB<T, Io1, Io2>
+    where
+        Io2: AsyncRead + AsyncWrite + 'static,
+        T: Service<Request = Connect, Response = (Connect, Io2), Error = ConnectorError>,
+    {
+        fut: <ConnectionPool<T, Io2> as Service>::Future,
+        _t: PhantomData<Io1>,
+    }
+
+    impl<T, Io1, Io2> Future for InnerConnectorResponseB<T, Io1, Io2>
+    where
+        T: Service<Request = Connect, Response = (Connect, Io2), Error = ConnectorError>,
+        Io1: AsyncRead + AsyncWrite + 'static,
+        Io2: AsyncRead + AsyncWrite + 'static,
+    {
+        type Item = IoEither<Connection<Io1>, Connection<Io2>>;
+        type Error = ConnectorError;
+
+        fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+            match self.fut.poll()? {
+                Async::NotReady => Ok(Async::NotReady),
+                Async::Ready(res) => Ok(Async::Ready(IoEither::B(res))),
+            }
+        }
+    }
+}
+
+pub(crate) enum IoEither<Io1, Io2> {
+    A(Io1),
+    B(Io2),
+}
+
+impl<Io1, Io2> io::Read for IoEither<Io1, Io2>
+where
+    Io1: io::Read,
+    Io2: io::Read,
+{
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        match self {
+            IoEither::A(ref mut io) => io.read(buf),
+            IoEither::B(ref mut io) => io.read(buf),
+        }
+    }
+}
+
+impl<Io1, Io2> AsyncRead for IoEither<Io1, Io2>
+where
+    Io1: AsyncRead,
+    Io2: AsyncRead,
+{
+    unsafe fn prepare_uninitialized_buffer(&self, buf: &mut [u8]) -> bool {
+        match self {
+            IoEither::A(ref io) => io.prepare_uninitialized_buffer(buf),
+            IoEither::B(ref io) => io.prepare_uninitialized_buffer(buf),
+        }
+    }
+}
+
+impl<Io1, Io2> AsyncWrite for IoEither<Io1, Io2>
+where
+    Io1: AsyncWrite,
+    Io2: AsyncWrite,
+{
+    fn shutdown(&mut self) -> Poll<(), io::Error> {
+        match self {
+            IoEither::A(ref mut io) => io.shutdown(),
+            IoEither::B(ref mut io) => io.shutdown(),
+        }
+    }
+
+    fn poll_write(&mut self, buf: &[u8]) -> Poll<usize, io::Error> {
+        match self {
+            IoEither::A(ref mut io) => io.poll_write(buf),
+            IoEither::B(ref mut io) => io.poll_write(buf),
+        }
+    }
+
+    fn poll_flush(&mut self) -> Poll<(), io::Error> {
+        match self {
+            IoEither::A(ref mut io) => io.poll_flush(),
+            IoEither::B(ref mut io) => io.poll_flush(),
+        }
+    }
+}
+
+impl<Io1, Io2> io::Write for IoEither<Io1, Io2>
+where
+    Io1: io::Write,
+    Io2: io::Write,
+{
+    fn flush(&mut self) -> io::Result<()> {
+        match self {
+            IoEither::A(ref mut io) => io.flush(),
+            IoEither::B(ref mut io) => io.flush(),
+        }
+    }
+
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        match self {
+            IoEither::A(ref mut io) => io.write(buf),
+            IoEither::B(ref mut io) => io.write(buf),
+        }
+    }
+}
+
+impl<Io1, Io2> fmt::Debug for IoEither<Io1, Io2>
+where
+    Io1: fmt::Debug,
+    Io2: fmt::Debug,
+{
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            IoEither::A(ref io) => io.fmt(fmt),
+            IoEither::B(ref io) => io.fmt(fmt),
+        }
+    }
+}

src/client/error.rs

@@ -0,0 +1,77 @@
+use std::io;
+
+use trust_dns_resolver::error::ResolveError;
+
+#[cfg(feature = "ssl")]
+use openssl::ssl::Error as SslError;
+
+#[cfg(all(
+    feature = "tls",
+    not(any(feature = "ssl", feature = "rust-tls"))
+))]
+use native_tls::Error as SslError;
+
+#[cfg(all(
+    feature = "rust-tls",
+    not(any(feature = "tls", feature = "ssl"))
+))]
+use std::io::Error as SslError;
+
+/// A set of errors that can occur while connecting to an HTTP host
+#[derive(Fail, Debug)]
+pub enum ConnectorError {
+    /// Invalid URL
+    #[fail(display = "Invalid URL")]
+    InvalidUrl(InvalidUrlKind),
+
+    /// SSL feature is not enabled
+    #[fail(display = "SSL is not supported")]
+    SslIsNotSupported,
+
+    /// SSL error
+    #[cfg(any(feature = "tls", feature = "ssl", feature = "rust-tls"))]
+    #[fail(display = "{}", _0)]
+    SslError(#[cause] SslError),
+
+    /// Failed to resolve the hostname
+    #[fail(display = "Failed resolving hostname: {}", _0)]
+    Resolver(ResolveError),
+
+    /// No dns records
+    #[fail(display = "No dns records found for the input")]
+    NoRecords,
+
+    /// Connecting took too long
+    #[fail(display = "Timeout out while establishing connection")]
+    Timeout,
+
+    /// Connector has been disconnected
+    #[fail(display = "Internal error: connector has been disconnected")]
+    Disconnected,
+
+    /// Connection io error
+    #[fail(display = "{}", _0)]
+    IoError(io::Error),
+}
+
+#[derive(Fail, Debug)]
+pub enum InvalidUrlKind {
+    #[fail(display = "Missing url scheme")]
+    MissingScheme,
+    #[fail(display = "Unknown url scheme")]
+    UnknownScheme,
+    #[fail(display = "Missing host name")]
+    MissingHost,
+}
+
+impl From<io::Error> for ConnectorError {
+    fn from(err: io::Error) -> ConnectorError {
+        ConnectorError::IoError(err)
+    }
+}
+
+impl From<ResolveError> for ConnectorError {
+    fn from(err: ResolveError) -> ConnectorError {
+        ConnectorError::Resolver(err)
+    }
+}

src/client/mod.rs

@@ -1,6 +1,14 @@
 //! Http client api
+mod connect;
+mod connection;
+mod connector;
+mod error;
+mod pool;
 mod request;
 mod response;
 
+pub use self::connect::Connect;
+pub use self::connector::Connector;
+pub use self::error::{ConnectorError, InvalidUrlKind};
 pub use self::request::{ClientRequest, ClientRequestBuilder};
 pub use self::response::ClientResponse;

src/client/pool.rs

@@ -0,0 +1,579 @@
+use std::cell::RefCell;
+use std::collections::{HashMap, VecDeque};
+use std::io;
+use std::rc::Rc;
+use std::time::{Duration, Instant};
+
+use actix_net::service::Service;
+use futures::future::{ok, Either, FutureResult};
+use futures::sync::oneshot;
+use futures::task::AtomicTask;
+use futures::{Async, Future, Poll};
+use http::uri::Authority;
+use indexmap::IndexSet;
+use slab::Slab;
+use tokio_current_thread::spawn;
+use tokio_io::{AsyncRead, AsyncWrite};
+use tokio_timer::{sleep, Delay};
+
+use super::connect::Connect;
+use super::connection::Connection;
+use super::error::ConnectorError;
+
+#[derive(Hash, Eq, PartialEq, Clone, Debug)]
+pub(crate) struct Key {
+    authority: Authority,
+}
+
+impl From<Authority> for Key {
+    fn from(authority: Authority) -> Key {
+        Key { authority }
+    }
+}
+
+#[derive(Debug)]
+struct AvailableConnection<T> {
+    io: T,
+    used: Instant,
+    created: Instant,
+}
+
+/// Connections pool
+pub(crate) struct ConnectionPool<T, Io: AsyncRead + AsyncWrite + 'static>(
+    T,
+    Rc<RefCell<Inner<Io>>>,
+);
+
+impl<T, Io> ConnectionPool<T, Io>
+where
+    Io: AsyncRead + AsyncWrite + 'static,
+    T: Service<Request = Connect, Response = (Connect, Io), Error = ConnectorError>,
+{
+    pub(crate) fn new(
+        connector: T,
+        conn_lifetime: Duration,
+        conn_keep_alive: Duration,
+        disconnect_timeout: Option<Duration>,
+        limit: usize,
+    ) -> Self {
+        ConnectionPool(
+            connector,
+            Rc::new(RefCell::new(Inner {
+                conn_lifetime,
+                conn_keep_alive,
+                disconnect_timeout,
+                limit,
+                acquired: 0,
+                waiters: Slab::new(),
+                waiters_queue: IndexSet::new(),
+                available: HashMap::new(),
+                task: AtomicTask::new(),
+            })),
+        )
+    }
+}
+
+impl<T, Io> Clone for ConnectionPool<T, Io>
+where
+    T: Clone,
+    Io: AsyncRead + AsyncWrite + 'static,
+{
+    fn clone(&self) -> Self {
+        ConnectionPool(self.0.clone(), self.1.clone())
+    }
+}
+
+impl<T, Io> Service for ConnectionPool<T, Io>
+where
+    Io: AsyncRead + AsyncWrite + 'static,
+    T: Service<Request = Connect, Response = (Connect, Io), Error = ConnectorError>,
+{
+    type Request = Connect;
+    type Response = Connection<Io>;
+    type Error = ConnectorError;
+    type Future = Either<
+        FutureResult<Connection<Io>, ConnectorError>,
+        Either<WaitForConnection<Io>, OpenConnection<T::Future, Io>>,
+    >;
+
+    fn poll_ready(&mut self) -> Poll<(), Self::Error> {
+        self.0.poll_ready()
+    }
+
+    fn call(&mut self, req: Self::Request) -> Self::Future {
+        let key = req.key();
+
+        // acquire connection
+        match self.1.as_ref().borrow_mut().acquire(&key) {
+            Acquire::Acquired(io, created) => {
+                // use existing connection
+                Either::A(ok(Connection::new(
+                    io,
+                    created,
+                    Acquired(key, Some(self.1.clone())),
+                )))
+            }
+            Acquire::NotAvailable => {
+                // connection is not available, wait
+                let (rx, token) = self.1.as_ref().borrow_mut().wait_for(req);
+                Either::B(Either::A(WaitForConnection {
+                    rx,
+                    key,
+                    token,
+                    inner: Some(self.1.clone()),
+                }))
+            }
+            Acquire::Available => {
+                // open new connection
+                Either::B(Either::B(OpenConnection::new(
+                    key,
+                    self.1.clone(),
+                    self.0.call(req),
+                )))
+            }
+        }
+    }
+}
+
+#[doc(hidden)]
+pub struct WaitForConnection<Io>
+where
+    Io: AsyncRead + AsyncWrite + 'static,
+{
+    key: Key,
+    token: usize,
+    rx: oneshot::Receiver<Result<Connection<Io>, ConnectorError>>,
+    inner: Option<Rc<RefCell<Inner<Io>>>>,
+}
+
+impl<Io> Drop for WaitForConnection<Io>
+where
+    Io: AsyncRead + AsyncWrite + 'static,
+{
+    fn drop(&mut self) {
+        if let Some(i) = self.inner.take() {
+            let mut inner = i.as_ref().borrow_mut();
+            inner.release_waiter(&self.key, self.token);
+            inner.check_availibility();
+        }
+    }
+}
+
+impl<Io> Future for WaitForConnection<Io>
+where
+    Io: AsyncRead + AsyncWrite,
+{
+    type Item = Connection<Io>;
+    type Error = ConnectorError;
+
+    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+        match self.rx.poll() {
+            Ok(Async::Ready(item)) => match item {
+                Err(err) => Err(err),
+                Ok(conn) => {
+                    let _ = self.inner.take();
+                    Ok(Async::Ready(conn))
+                }
+            },
+            Ok(Async::NotReady) => Ok(Async::NotReady),
+            Err(_) => {
+                let _ = self.inner.take();
+                Err(ConnectorError::Disconnected)
+            }
+        }
+    }
+}
+
+#[doc(hidden)]
+pub struct OpenConnection<F, Io>
+where
+    Io: AsyncRead + AsyncWrite + 'static,
+{
+    fut: F,
+    key: Key,
+    inner: Option<Rc<RefCell<Inner<Io>>>>,
+}
+
+impl<F, Io> OpenConnection<F, Io>
+where
+    F: Future<Item = (Connect, Io), Error = ConnectorError>,
+    Io: AsyncRead + AsyncWrite + 'static,
+{
+    fn new(key: Key, inner: Rc<RefCell<Inner<Io>>>, fut: F) -> Self {
+        OpenConnection {
+            key,
+            fut,
+            inner: Some(inner),
+        }
+    }
+}
+
+impl<F, Io> Drop for OpenConnection<F, Io>
+where
+    Io: AsyncRead + AsyncWrite + 'static,
+{
+    fn drop(&mut self) {
+        if let Some(inner) = self.inner.take() {
+            let mut inner = inner.as_ref().borrow_mut();
+            inner.release();
+            inner.check_availibility();
+        }
+    }
+}
+
+impl<F, Io> Future for OpenConnection<F, Io>
+where
+    F: Future<Item = (Connect, Io), Error = ConnectorError>,
+    Io: AsyncRead + AsyncWrite,
+{
+    type Item = Connection<Io>;
+    type Error = ConnectorError;
+
+    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+        match self.fut.poll() {
+            Err(err) => Err(err.into()),
+            Ok(Async::Ready((_, io))) => {
+                let _ = self.inner.take();
+                Ok(Async::Ready(Connection::new(
+                    io,
+                    Instant::now(),
+                    Acquired(self.key.clone(), self.inner.clone()),
+                )))
+            }
+            Ok(Async::NotReady) => Ok(Async::NotReady),
+        }
+    }
+}
+
+struct OpenWaitingConnection<F, Io>
+where
+    Io: AsyncRead + AsyncWrite + 'static,
+{
+    fut: F,
+    key: Key,
+    rx: Option<oneshot::Sender<Result<Connection<Io>, ConnectorError>>>,
+    inner: Option<Rc<RefCell<Inner<Io>>>>,
+}
+
+impl<F, Io> OpenWaitingConnection<F, Io>
+where
+    F: Future<Item = (Connect, Io), Error = ConnectorError> + 'static,
+    Io: AsyncRead + AsyncWrite + 'static,
+{
+    fn spawn(
+        key: Key,
+        rx: oneshot::Sender<Result<Connection<Io>, ConnectorError>>,
+        inner: Rc<RefCell<Inner<Io>>>,
+        fut: F,
+    ) {
+        spawn(OpenWaitingConnection {
+            key,
+            fut,
+            rx: Some(rx),
+            inner: Some(inner),
+        })
+    }
+}
+
+impl<F, Io> Drop for OpenWaitingConnection<F, Io>
+where
+    Io: AsyncRead + AsyncWrite + 'static,
+{
+    fn drop(&mut self) {
+        if let Some(inner) = self.inner.take() {
+            let mut inner = inner.as_ref().borrow_mut();
+            inner.release();
+            inner.check_availibility();
+        }
+    }
+}
+
+impl<F, Io> Future for OpenWaitingConnection<F, Io>
+where
+    F: Future<Item = (Connect, Io), Error = ConnectorError>,
+    Io: AsyncRead + AsyncWrite,
+{
+    type Item = ();
+    type Error = ();
+
+    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+        match self.fut.poll() {
+            Err(err) => {
+                let _ = self.inner.take();
+                if let Some(rx) = self.rx.take() {
+                    let _ = rx.send(Err(err));
+                }
+                Err(())
+            }
+            Ok(Async::Ready((_, io))) => {
+                let _ = self.inner.take();
+                if let Some(rx) = self.rx.take() {
+                    let _ = rx.send(Ok(Connection::new(
+                        io,
+                        Instant::now(),
+                        Acquired(self.key.clone(), self.inner.clone()),
+                    )));
+                }
+                Ok(Async::Ready(()))
+            }
+            Ok(Async::NotReady) => Ok(Async::NotReady),
+        }
+    }
+}
+
+enum Acquire<T> {
+    Acquired(T, Instant),
+    Available,
+    NotAvailable,
+}
+
+pub(crate) struct Inner<Io>
+where
+    Io: AsyncRead + AsyncWrite + 'static,
+{
+    conn_lifetime: Duration,
+    conn_keep_alive: Duration,
+    disconnect_timeout: Option<Duration>,
+    limit: usize,
+    acquired: usize,
+    available: HashMap<Key, VecDeque<AvailableConnection<Io>>>,
+    waiters: Slab<(
+        Connect,
+        oneshot::Sender<Result<Connection<Io>, ConnectorError>>,
+    )>,
+    waiters_queue: IndexSet<(Key, usize)>,
+    task: AtomicTask,
+}
+
+impl<Io> Inner<Io>
+where
+    Io: AsyncRead + AsyncWrite + 'static,
+{
+    /// connection is not available, wait
+    fn wait_for(
+        &mut self,
+        connect: Connect,
+    ) -> (
+        oneshot::Receiver<Result<Connection<Io>, ConnectorError>>,
+        usize,
+    ) {
+        let (tx, rx) = oneshot::channel();
+
+        let key = connect.key();
+        let entry = self.waiters.vacant_entry();
+        let token = entry.key();
+        entry.insert((connect, tx));
+        assert!(!self.waiters_queue.insert((key, token)));
+        (rx, token)
+    }
+
+    fn release_waiter(&mut self, key: &Key, token: usize) {
+        self.waiters.remove(token);
+        self.waiters_queue.remove(&(key.clone(), token));
+    }
+
+    fn acquire(&mut self, key: &Key) -> Acquire<Io> {
+        // check limits
+        if self.limit > 0 && self.acquired >= self.limit {
+            return Acquire::NotAvailable;
+        }
+
+        self.reserve();
+
+        // check if open connection is available
+        // cleanup stale connections at the same time
+        if let Some(ref mut connections) = self.available.get_mut(key) {
+            let now = Instant::now();
+            while let Some(conn) = connections.pop_back() {
+                // check if it still usable
+                if (now - conn.used) > self.conn_keep_alive
+                    || (now - conn.created) > self.conn_lifetime
+                {
+                    if let Some(timeout) = self.disconnect_timeout {
+                        spawn(CloseConnection::new(conn.io, timeout))
+                    }
+                } else {
+                    let mut io = conn.io;
+                    let mut buf = [0; 2];
+                    match io.read(&mut buf) {
+                        Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => (),
+                        Ok(n) if n > 0 => {
+                            if let Some(timeout) = self.disconnect_timeout {
+                                spawn(CloseConnection::new(io, timeout))
+                            }
+                            continue;
+                        }
+                        Ok(_) | Err(_) => continue,
+                    }
+                    return Acquire::Acquired(io, conn.created);
+                }
+            }
+        }
+        Acquire::Available
+    }
+
+    fn reserve(&mut self) {
+        self.acquired += 1;
+    }
+
+    fn release(&mut self) {
+        self.acquired -= 1;
+    }
+
+    fn release_conn(&mut self, key: &Key, io: Io, created: Instant) {
+        self.acquired -= 1;
+        self.available
+            .entry(key.clone())
+            .or_insert_with(VecDeque::new)
+            .push_back(AvailableConnection {
+                io,
+                created,
+                used: Instant::now(),
+            });
+    }
+
+    fn release_close(&mut self, io: Io) {
+        self.acquired -= 1;
+        if let Some(timeout) = self.disconnect_timeout {
+            spawn(CloseConnection::new(io, timeout))
+        }
+    }
+
+    fn check_availibility(&self) {
+        if !self.waiters_queue.is_empty() && self.acquired < self.limit {
+            self.task.notify()
+        }
+    }
+}
+
+struct ConnectorPoolSupport<T, Io>
+where
+    Io: AsyncRead + AsyncWrite + 'static,
+{
+    connector: T,
+    inner: Rc<RefCell<Inner<Io>>>,
+}
+
+impl<T, Io> Future for ConnectorPoolSupport<T, Io>
+where
+    Io: AsyncRead + AsyncWrite + 'static,
+    T: Service<Request = Connect, Response = (Connect, Io), Error = ConnectorError>,
+    T::Future: 'static,
+{
+    type Item = ();
+    type Error = ();
+
+    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+        let mut inner = self.inner.as_ref().borrow_mut();
+        inner.task.register();
+
+        // check waiters
+        loop {
+            let (key, token) = {
+                if let Some((key, token)) = inner.waiters_queue.get_index(0) {
+                    (key.clone(), *token)
+                } else {
+                    break;
+                }
+            };
+            match inner.acquire(&key) {
+                Acquire::NotAvailable => break,
+                Acquire::Acquired(io, created) => {
+                    let (_, tx) = inner.waiters.remove(token);
+                    if let Err(conn) = tx.send(Ok(Connection::new(
+                        io,
+                        created,
+                        Acquired(key.clone(), Some(self.inner.clone())),
+                    ))) {
+                        let (io, created) = conn.unwrap().into_inner();
+                        inner.release_conn(&key, io, created);
+                    }
+                }
+                Acquire::Available => {
+                    let (connect, tx) = inner.waiters.remove(token);
+                    OpenWaitingConnection::spawn(
+                        key.clone(),
+                        tx,
+                        self.inner.clone(),
+                        self.connector.call(connect),
+                    );
+                }
+            }
+            let _ = inner.waiters_queue.swap_remove_index(0);
+        }
+
+        Ok(Async::NotReady)
+    }
+}
+
+struct CloseConnection<T> {
+    io: T,
+    timeout: Delay,
+}
+
+impl<T> CloseConnection<T>
+where
+    T: AsyncWrite,
+{
+    fn new(io: T, timeout: Duration) -> Self {
+        CloseConnection {
+            io,
+            timeout: sleep(timeout),
+        }
+    }
+}
+
+impl<T> Future for CloseConnection<T>
+where
+    T: AsyncWrite,
+{
+    type Item = ();
+    type Error = ();
+
+    fn poll(&mut self) -> Poll<(), ()> {
+        match self.timeout.poll() {
+            Ok(Async::Ready(_)) | Err(_) => Ok(Async::Ready(())),
+            Ok(Async::NotReady) => match self.io.shutdown() {
+                Ok(Async::Ready(_)) | Err(_) => Ok(Async::Ready(())),
+                Ok(Async::NotReady) => Ok(Async::NotReady),
+            },
+        }
+    }
+}
+
+pub(crate) struct Acquired<T: AsyncRead + AsyncWrite + 'static>(
+    Key,
+    Option<Rc<RefCell<Inner<T>>>>,
+);
+
+impl<T> Acquired<T>
+where
+    T: AsyncRead + AsyncWrite + 'static,
+{
+    pub(crate) fn close(&mut self, conn: Connection<T>) {
+        if let Some(inner) = self.1.take() {
+            let (io, _) = conn.into_inner();
+            inner.as_ref().borrow_mut().release_close(io);
+        }
+    }
+    pub(crate) fn release(&mut self, conn: Connection<T>) {
+        if let Some(inner) = self.1.take() {
+            let (io, created) = conn.into_inner();
+            inner
+                .as_ref()
+                .borrow_mut()
+                .release_conn(&self.0, io, created);
+        }
+    }
+}
+
+impl<T> Drop for Acquired<T>
+where
+    T: AsyncRead + AsyncWrite + 'static,
+{
+    fn drop(&mut self) {
+        if let Some(inner) = self.1.take() {
+            inner.as_ref().borrow_mut().release();
+        }
+    }
+}

src/lib.rs

@@ -83,6 +83,7 @@ extern crate cookie;
 extern crate encoding;
 extern crate http as modhttp;
 extern crate httparse;
+extern crate indexmap;
 extern crate mime;
 extern crate net2;
 extern crate percent_encoding;
@@ -90,18 +91,24 @@ extern crate rand;
 extern crate serde;
 extern crate serde_json;
 extern crate serde_urlencoded;
+extern crate slab;
 extern crate tokio;
 extern crate tokio_codec;
 extern crate tokio_current_thread;
 extern crate tokio_io;
 extern crate tokio_tcp;
 extern crate tokio_timer;
+extern crate trust_dns_proto;
+extern crate trust_dns_resolver;
 extern crate url as urlcrate;
 
 #[cfg(test)]
 #[macro_use]
 extern crate serde_derive;
 
+#[cfg(feature = "ssl")]
+extern crate openssl;
+
 mod body;
 pub mod client;
 mod config;