feat(client): add support to set SO_NODELAY on client HTTP sockets

Add configuration on `HttpConnector` to set `SO_NODELAY` on client
HTTP sockets.

Closes #1473

src/client/connect.rs

@@ -170,6 +170,7 @@ pub struct HttpConnector {
  enforce_http: bool,
  handle: Option<Handle>,
  keep_alive_timeout: Option<Duration>,
+ nodelay: bool,
 }
 
 impl HttpConnector {
@@ -205,6 +206,7 @@ impl HttpConnector {
  enforce_http: true,
  handle,
  keep_alive_timeout: None,
+ nodelay: false,
  }
  }
 
@@ -225,6 +227,14 @@ impl HttpConnector {
  pub fn set_keepalive(&mut self, dur: Option<Duration>) {
  self.keep_alive_timeout = dur;
  }
+
+ /// Set that all sockets have `SO_NODELAY` set to the supplied value `nodelay`.
+ ///
+ /// Default is `false`.
+ #[inline]
+ pub fn set_nodelay(&mut self, nodelay: bool) {
+ self.nodelay = nodelay;
+ }
 }
 
 impl fmt::Debug for HttpConnector {
@@ -264,6 +274,7 @@ impl Connect for HttpConnector {
  state: State::Lazy(self.executor.clone(), host.into(), port),
  handle: self.handle.clone(),
  keep_alive_timeout: self.keep_alive_timeout,
+ nodelay: self.nodelay,
  }
  }
 }
@@ -274,6 +285,7 @@ fn invalid_url(err: InvalidUrl, handle: &Option<Handle>) -> HttpConnecting {
  state: State::Error(Some(io::Error::new(io::ErrorKind::InvalidInput, err))),
  handle: handle.clone(),
  keep_alive_timeout: None,
+ nodelay: false,
  }
 }
 
@@ -306,6 +318,7 @@ pub struct HttpConnecting {
  state: State,
  handle: Option<Handle>,
  keep_alive_timeout: Option<Duration>,
+ nodelay: bool,
 }
 
 enum State {
@@ -355,6 +368,8 @@ impl Future for HttpConnecting {
  sock.set_keepalive(Some(dur))?;
  }
 
+ sock.set_nodelay(self.nodelay)?;
+
  return Ok(Async::Ready((sock, Connected::new())));
  },
  State::Error(ref mut e) => return Err(e.take().expect("polled more than once")),