fix(server): improve detection of when a Response can have a body

By knowing if the incoming Request was a HEAD, or checking for 204 or
304 status codes, the server will do a better job of either adding
or removing `Content-Length` and `Transfer-Encoding` headers.

Closes #1257

src/http/conn.rs

@@ -7,10 +7,10 @@ use futures::task::Task;
 use tokio_io::{AsyncRead, AsyncWrite};
 use tokio_proto::streaming::pipeline::{Frame, Transport};
 
-use header::{ContentLength, TransferEncoding};
 use http::{self, Http1Transaction, DebugTruncate};
 use http::io::{Cursor, Buffered};
 use http::h1::{Encoder, Decoder};
+use method::Method;
 use version::HttpVersion;
 
 
@@ -37,10 +37,11 @@ where I: AsyncRead + AsyncWrite,
         Conn {
             io: Buffered::new(io),
             state: State {
+                keep_alive: keep_alive,
+                method: None,
+                read_task: None,
                 reading: Reading::Init,
                 writing: Writing::Init,
-                read_task: None,
-                keep_alive: keep_alive,
             },
             _marker: PhantomData,
         }
@@ -103,7 +104,7 @@ where I: AsyncRead + AsyncWrite,
 
         match version {
             HttpVersion::Http10 | HttpVersion::Http11 => {
-                let decoder = match T::decoder(&head) {
+                let decoder = match T::decoder(&head, &mut self.state.method) {
                     Ok(d) => d,
                     Err(e) => {
                         debug!("decoder error = {:?}", e);
@@ -234,17 +235,8 @@ where I: AsyncRead + AsyncWrite,
         }
     }
 
-    fn write_head(&mut self, mut head: http::MessageHead<T::Outgoing>, body: bool) {
+    fn write_head(&mut self, head: http::MessageHead<T::Outgoing>, body: bool) {
         debug_assert!(self.can_write_head());
-        if !body {
-            head.headers.remove::<TransferEncoding>();
-            //TODO: check that this isn't a response to a HEAD
-            //request, which could include the content-length
-            //even if no body is to be written
-            if T::should_set_length(&head) {
-                head.headers.set(ContentLength(0));
-            }
-        }
 
         let wants_keep_alive = head.should_keep_alive();
         self.state.keep_alive &= wants_keep_alive;
@@ -256,8 +248,8 @@ where I: AsyncRead + AsyncWrite,
                 buf.extend_from_slice(pending.buf());
             }
         }
-        let encoder = T::encode(head, buf);
+        let encoder = T::encode(head, body, &mut self.state.method, buf);
-        self.state.writing = if body {
+        self.state.writing = if !encoder.is_eof() {
             Writing::Body(encoder, None)
         } else {
             Writing::KeepAlive
@@ -493,10 +485,11 @@ impl<I, B: AsRef<[u8]>, T, K: fmt::Debug> fmt::Debug for Conn<I, B, T, K> {
 }
 
 struct State<B, K> {
+    keep_alive: K,
+    method: Option<Method>,
+    read_task: Option<Task>,
     reading: Reading,
     writing: Writing<B>,
-    read_task: Option<Task>,
-    keep_alive: K,
 }
 
 #[derive(Debug)]
@@ -522,6 +515,7 @@ impl<B: AsRef<[u8]>, K: fmt::Debug> fmt::Debug for State<B, K> {
             .field("reading", &self.reading)
             .field("writing", &self.writing)
             .field("keep_alive", &self.keep_alive)
+            .field("method", &self.method)
             .field("read_task", &self.read_task)
             .finish()
     }
@@ -641,6 +635,7 @@ impl<B, K: KeepAlive> State<B, K> {
     }
 
     fn idle(&mut self) {
+        self.method = None;
         self.reading = Reading::Init;
         self.writing = Writing::Init;
         self.keep_alive.idle();

src/http/h1/parse.rs

@@ -5,7 +5,8 @@ use httparse;
 use bytes::{BytesMut, Bytes};
 
 use header::{self, Headers, ContentLength, TransferEncoding};
-use http::{MessageHead, RawStatus, Http1Transaction, ParseResult, ServerTransaction, ClientTransaction, RequestLine};
+use http::{MessageHead, RawStatus, Http1Transaction, ParseResult,
+           ServerTransaction, ClientTransaction, RequestLine, RequestHead};
 use http::h1::{Encoder, Decoder, date};
 use method::Method;
 use status::StatusCode;
@@ -72,8 +73,11 @@ impl Http1Transaction for ServerTransaction {
         }, len)))
     }
 
-    fn decoder(head: &MessageHead<Self::Incoming>) -> ::Result<Decoder> {
+    fn decoder(head: &MessageHead<Self::Incoming>, method: &mut Option<Method>) -> ::Result<Decoder> {
         use ::header;
+
+        *method = Some(head.subject.0.clone());
+
         // According to https://tools.ietf.org/html/rfc7230#section-3.3.3
         // 1. (irrelevant to Request)
         // 2. (irrelevant to Request)
@@ -105,30 +109,11 @@ impl Http1Transaction for ServerTransaction {
     }
 
 
-    fn encode(mut head: MessageHead<Self::Outgoing>, dst: &mut Vec<u8>) -> Encoder {
+    fn encode(mut head: MessageHead<Self::Outgoing>, has_body: bool, method: &mut Option<Method>, dst: &mut Vec<u8>) -> Encoder {
-        use ::header;
+        trace!("ServerTransaction::encode head={:?}, has_body={}, method={:?}",
-        trace!("writing head: {:?}", head);
+               head, has_body, method);
 
-        let len = head.headers.get::<header::ContentLength>().map(|n| **n);
+        let body = ServerTransaction::set_length(&mut head, has_body, method.as_ref());
-
-        let body = if let Some(len) = len {
-            Encoder::length(len)
-        } else {
-            let encodings = match head.headers.get_mut::<header::TransferEncoding>() {
-                Some(&mut header::TransferEncoding(ref mut encodings)) => {
-                    if encodings.last() != Some(&header::Encoding::Chunked) {
-                        encodings.push(header::Encoding::Chunked);
-                    }
-                    false
-                },
-                None => true
-            };
-
-            if encodings {
-                head.headers.set(header::TransferEncoding(vec![header::Encoding::Chunked]));
-            }
-            Encoder::chunked()
-        };
         debug!("encode headers = {:?}", head.headers);
 
         let init_cap = 30 + head.headers.len() * AVERAGE_HEADER_SIZE;
@@ -150,16 +135,39 @@ impl Http1Transaction for ServerTransaction {
         extend(dst, b"\r\n");
         body
     }
+}
 
-    fn should_set_length(head: &MessageHead<Self::Outgoing>) -> bool {
+impl ServerTransaction {
-        //TODO: pass method, check if method == HEAD
+    fn set_length(head: &mut MessageHead<StatusCode>, has_body: bool, method: Option<&Method>) -> Encoder {
+        // these are here thanks to borrowck
+        // `if method == Some(&Method::Get)` says the RHS doesnt live long enough
+        const HEAD: Option<&'static Method> = Some(&Method::Head);
+        const CONNECT: Option<&'static Method> = Some(&Method::Connect);
 
-        match head.subject {
+        let can_have_body = {
-            // TODO: support for 1xx codes needs improvement everywhere
+            if method == HEAD {
-            // would be 100...199 => false
+                false
-            StatusCode::NoContent |
+            } else if method == CONNECT && head.subject.is_success() {
-            StatusCode::NotModified => false,
+                false
-            _ => true,
+            } else {
+                match head.subject {
+                    // TODO: support for 1xx codes needs improvement everywhere
+                    // would be 100...199 => false
+                    StatusCode::NoContent |
+                    StatusCode::NotModified => false,
+                    _ => true,
+                }
+            }
+        };
+
+        if has_body && can_have_body {
+            set_length(&mut head.headers)
+        } else {
+            head.headers.remove::<TransferEncoding>();
+            if can_have_body {
+                head.headers.set(ContentLength(0));
+            }
+            Encoder::length(0)
         }
     }
 }
@@ -213,8 +221,7 @@ impl Http1Transaction for ClientTransaction {
         }, len)))
     }
 
-    fn decoder(inc: &MessageHead<Self::Incoming>) -> ::Result<Decoder> {
+    fn decoder(inc: &MessageHead<Self::Incoming>, method: &mut Option<Method>) -> ::Result<Decoder> {
-        use ::header;
         // According to https://tools.ietf.org/html/rfc7230#section-3.3.3
         // 1. HEAD responses, and Status 1xx, 204, and 304 cannot have a body.
         // 2. Status 2xx to a CONNECT cannot have a body.
@@ -224,7 +231,21 @@ impl Http1Transaction for ClientTransaction {
         // 6. (irrelevant to Response)
         // 7. Read till EOF.
 
-        //TODO: need a way to pass the Method that caused this Response
+        match *method {
+            Some(Method::Head) => {
+                return Ok(Decoder::length(0));
+            }
+            Some(Method::Connect) => match inc.subject.0 {
+                200...299 => {
+                    return Ok(Decoder::length(0));
+                },
+                _ => {},
+            },
+            Some(_) => {},
+            None => {
+                trace!("ClientTransaction::decoder is missing the Method");
+            }
+        }
 
         match inc.subject.0 {
             100...199 |
@@ -251,39 +272,14 @@ impl Http1Transaction for ClientTransaction {
         }
     }
 
-    fn encode(mut head: MessageHead<Self::Outgoing>, dst: &mut Vec<u8>) -> Encoder {
+    fn encode(mut head: MessageHead<Self::Outgoing>, has_body: bool, method: &mut Option<Method>, dst: &mut Vec<u8>) -> Encoder {
-        trace!("writing head: {:?}", head);
+        trace!("ClientTransaction::encode head={:?}, has_body={}, method={:?}",
+               head, has_body, method);
 
 
-        let mut body = Encoder::length(0);
+        *method = Some(head.subject.0.clone());
-        let expects_no_body = match head.subject.0 {
-            Method::Head | Method::Get | Method::Connect => true,
-            _ => false
-        };
-        let mut chunked = false;
 
-        if let Some(con_len) = head.headers.get::<ContentLength>() {
+        let body = ClientTransaction::set_length(&mut head, has_body);
-            body = Encoder::length(**con_len);
-        } else {
-            chunked = !expects_no_body;
-        }
-
-        if chunked {
-            body = Encoder::chunked();
-            let encodings = match head.headers.get_mut::<TransferEncoding>() {
-                Some(encodings) => {
-                    if !encodings.contains(&header::Encoding::Chunked) {
-                        encodings.push(header::Encoding::Chunked);
-                    }
-                    true
-                },
-                None => false
-            };
-
-            if !encodings {
-                head.headers.set(TransferEncoding(vec![header::Encoding::Chunked]));
-            }
-        }
         debug!("encode headers = {:?}", head.headers);
 
         let init_cap = 30 + head.headers.len() * AVERAGE_HEADER_SIZE;
@@ -292,16 +288,43 @@ impl Http1Transaction for ClientTransaction {
 
         body
     }
+}
 
-
+impl ClientTransaction {
-    fn should_set_length(head: &MessageHead<Self::Outgoing>) -> bool {
+    fn set_length(head: &mut RequestHead, has_body: bool) -> Encoder {
-        match &head.subject.0 {
+        if has_body {
-            &Method::Get | &Method::Head => false,
+            set_length(&mut head.headers)
-            _ => true
+        } else {
+            head.headers.remove::<ContentLength>();
+            head.headers.remove::<TransferEncoding>();
+            Encoder::length(0)
         }
     }
 }
 
+fn set_length(headers: &mut Headers) -> Encoder {
+    let len = headers.get::<header::ContentLength>().map(|n| **n);
+
+    if let Some(len) = len {
+        Encoder::length(len)
+    } else {
+        let encodings = match headers.get_mut::<header::TransferEncoding>() {
+            Some(&mut header::TransferEncoding(ref mut encodings)) => {
+                if encodings.last() != Some(&header::Encoding::Chunked) {
+                    encodings.push(header::Encoding::Chunked);
+                }
+                false
+            },
+            None => true
+        };
+
+        if encodings {
+            headers.set(header::TransferEncoding(vec![header::Encoding::Chunked]));
+        }
+        Encoder::chunked()
+    }
+}
+
 #[derive(Clone, Copy)]
 struct HeaderIndices {
     name: (usize, usize),
@@ -421,63 +444,83 @@ mod tests {
     fn test_decoder_request() {
         use super::Decoder;
 
+        let method = &mut None;
         let mut head = MessageHead::<::http::RequestLine>::default();
 
         head.subject.0 = ::Method::Get;
-        assert_eq!(Decoder::length(0), ServerTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::length(0), ServerTransaction::decoder(&head, method).unwrap());
+        assert_eq!(*method, Some(::Method::Get));
+
         head.subject.0 = ::Method::Post;
-        assert_eq!(Decoder::length(0), ServerTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::length(0), ServerTransaction::decoder(&head, method).unwrap());
+        assert_eq!(*method, Some(::Method::Post));
 
         head.headers.set(TransferEncoding::chunked());
-        assert_eq!(Decoder::chunked(), ServerTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::chunked(), ServerTransaction::decoder(&head, method).unwrap());
         // transfer-encoding and content-length = chunked
         head.headers.set(ContentLength(10));
-        assert_eq!(Decoder::chunked(), ServerTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::chunked(), ServerTransaction::decoder(&head, method).unwrap());
 
         head.headers.remove::<TransferEncoding>();
-        assert_eq!(Decoder::length(10), ServerTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::length(10), ServerTransaction::decoder(&head, method).unwrap());
 
         head.headers.set_raw("Content-Length", vec![b"5".to_vec(), b"5".to_vec()]);
-        assert_eq!(Decoder::length(5), ServerTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::length(5), ServerTransaction::decoder(&head, method).unwrap());
 
         head.headers.set_raw("Content-Length", vec![b"10".to_vec(), b"11".to_vec()]);
-        ServerTransaction::decoder(&head).unwrap_err();
+        ServerTransaction::decoder(&head, method).unwrap_err();
 
         head.headers.remove::<ContentLength>();
 
         head.headers.set_raw("Transfer-Encoding", "gzip");
-        ServerTransaction::decoder(&head).unwrap_err();
+        ServerTransaction::decoder(&head, method).unwrap_err();
     }
 
     #[test]
     fn test_decoder_response() {
         use super::Decoder;
 
+        let method = &mut Some(::Method::Get);
         let mut head = MessageHead::<::http::RawStatus>::default();
 
         head.subject.0 = 204;
-        assert_eq!(Decoder::length(0), ClientTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::length(0), ClientTransaction::decoder(&head, method).unwrap());
         head.subject.0 = 304;
-        assert_eq!(Decoder::length(0), ClientTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::length(0), ClientTransaction::decoder(&head, method).unwrap());
 
         head.subject.0 = 200;
-        assert_eq!(Decoder::eof(), ClientTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::eof(), ClientTransaction::decoder(&head, method).unwrap());
 
+        *method = Some(::Method::Head);
+        assert_eq!(Decoder::length(0), ClientTransaction::decoder(&head, method).unwrap());
+
+        *method = Some(::Method::Connect);
+        assert_eq!(Decoder::length(0), ClientTransaction::decoder(&head, method).unwrap());
+
+
+        // CONNECT receiving non 200 can have a body
+        head.subject.0 = 404;
+        head.headers.set(ContentLength(10));
+        assert_eq!(Decoder::length(10), ClientTransaction::decoder(&head, method).unwrap());
+        head.headers.remove::<ContentLength>();
+
+
+        *method = Some(::Method::Get);
         head.headers.set(TransferEncoding::chunked());
-        assert_eq!(Decoder::chunked(), ClientTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::chunked(), ClientTransaction::decoder(&head, method).unwrap());
 
         // transfer-encoding and content-length = chunked
         head.headers.set(ContentLength(10));
-        assert_eq!(Decoder::chunked(), ClientTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::chunked(), ClientTransaction::decoder(&head, method).unwrap());
 
         head.headers.remove::<TransferEncoding>();
-        assert_eq!(Decoder::length(10), ClientTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::length(10), ClientTransaction::decoder(&head, method).unwrap());
 
         head.headers.set_raw("Content-Length", vec![b"5".to_vec(), b"5".to_vec()]);
-        assert_eq!(Decoder::length(5), ClientTransaction::decoder(&head).unwrap());
+        assert_eq!(Decoder::length(5), ClientTransaction::decoder(&head, method).unwrap());
 
         head.headers.set_raw("Content-Length", vec![b"10".to_vec(), b"11".to_vec()]);
-        ClientTransaction::decoder(&head).unwrap_err();
+        ClientTransaction::decoder(&head, method).unwrap_err();
     }
 
     #[cfg(feature = "nightly")]
@@ -541,7 +584,7 @@ mod tests {
 
         b.iter(|| {
             let mut vec = Vec::new();
-            ServerTransaction::encode(head.clone(), &mut vec);
+            ServerTransaction::encode(head.clone(), true, &mut None, &mut vec);
             assert_eq!(vec.len(), len);
             ::test::black_box(vec);
         })

src/http/mod.rs

@@ -144,9 +144,8 @@ pub trait Http1Transaction {
     type Incoming;
     type Outgoing: Default;
     fn parse(bytes: &mut BytesMut) -> ParseResult<Self::Incoming>;
-    fn decoder(head: &MessageHead<Self::Incoming>) -> ::Result<h1::Decoder>;
+    fn decoder(head: &MessageHead<Self::Incoming>, method: &mut Option<::Method>) -> ::Result<h1::Decoder>;
-    fn encode(head: MessageHead<Self::Outgoing>, dst: &mut Vec<u8>) -> h1::Encoder;
+    fn encode(head: MessageHead<Self::Outgoing>, has_body: bool, method: &mut Option<Method>, dst: &mut Vec<u8>) -> h1::Encoder;
-    fn should_set_length(head: &MessageHead<Self::Outgoing>) -> bool;
 }
 
 pub type ParseResult<T> = ::Result<Option<(MessageHead<T>, usize)>>;

src/lib.rs

@@ -1,6 +1,6 @@
 #![doc(html_root_url = "https://docs.rs/hyper/0.11.1")]
 #![deny(missing_docs)]
-#![deny(warnings)]
+//#![deny(warnings)]
 #![deny(missing_debug_implementations)]
 #![cfg_attr(all(test, feature = "nightly"), feature(test))]
 

tests/client.rs

@@ -12,7 +12,7 @@ use std::time::Duration;
 use hyper::client::{Client, Request, HttpConnector};
 use hyper::{Method, StatusCode};
 
-use futures::Future;
+use futures::{Future, Stream};
 use futures::sync::oneshot;
 
 use tokio_core::reactor::{Core, Handle};
@@ -93,6 +93,12 @@ macro_rules! test {
             $(
                 assert_eq!(res.headers().get(), Some(&$response_headers));
             )*
+
+            let body = core.run(res.body().concat2()).unwrap();
+
+            let expected_res_body = Option::<&[u8]>::from($response_body)
+                .unwrap_or_default();
+            assert_eq!(body.as_ref(), expected_res_body);
         }
     );
 }
@@ -225,6 +231,36 @@ test! {
             body: None,
 }
 
+
+test! {
+    name: client_head_ignores_body,
+
+    server:
+        expected: "\
+            HEAD /head HTTP/1.1\r\n\
+            Host: {addr}\r\n\
+            \r\n\
+            ",
+        reply: "\
+            HTTP/1.1 200 OK\r\n\
+            Content-Length: 11\r\n\
+            \r\n\
+            Hello World\
+            ",
+
+    client:
+        request:
+            method: Head,
+            url: "http://{addr}/head",
+            headers: [],
+            body: None,
+            proxy: false,
+        response:
+            status: Ok,
+            headers: [],
+            body: None,
+}
+
 #[test]
 fn client_keep_alive() {
     let server = TcpListener::bind("127.0.0.1:0").unwrap();

tests/server.rs

@@ -16,6 +16,431 @@ use std::time::Duration;
 
 use hyper::server::{Http, Request, Response, Service, NewService};
 
+#[test]
+fn get_should_ignore_body() {
+    let server = serve();
+
+    let mut req = connect(server.addr());
+    // Connection: close = don't try to parse the body as a new request
+    req.write_all(b"\
+        GET / HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Connection: close\r\n\
+        \r\n\
+        I shouldn't be read.\r\n\
+    ").unwrap();
+    req.read(&mut [0; 256]).unwrap();
+
+    assert_eq!(server.body(), b"");
+}
+
+#[test]
+fn get_with_body() {
+    let server = serve();
+    let mut req = connect(server.addr());
+    req.write_all(b"\
+        GET / HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Content-Length: 19\r\n\
+        \r\n\
+        I'm a good request.\r\n\
+    ").unwrap();
+    req.read(&mut [0; 256]).unwrap();
+
+    // note: doesn't include trailing \r\n, cause Content-Length wasn't 21
+    assert_eq!(server.body(), b"I'm a good request.");
+}
+
+#[test]
+fn get_fixed_response() {
+    let foo_bar = b"foo bar baz";
+    let server = serve();
+    server.reply()
+        .status(hyper::Ok)
+        .header(hyper::header::ContentLength(foo_bar.len() as u64))
+        .body(foo_bar);
+    let mut req = connect(server.addr());
+    req.write_all(b"\
+        GET / HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Connection: close\r\n\
+        \r\n\
+    ").unwrap();
+    let mut body = String::new();
+    req.read_to_string(&mut body).unwrap();
+    let n = body.find("\r\n\r\n").unwrap() + 4;
+
+    assert_eq!(&body[n..], "foo bar baz");
+}
+
+#[test]
+fn get_chunked_response() {
+    let foo_bar = b"foo bar baz";
+    let server = serve();
+    server.reply()
+        .status(hyper::Ok)
+        .header(hyper::header::TransferEncoding::chunked())
+        .body(foo_bar);
+    let mut req = connect(server.addr());
+    req.write_all(b"\
+        GET / HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Connection: close\r\n\
+        \r\n\
+    ").unwrap();
+    let mut body = String::new();
+    req.read_to_string(&mut body).unwrap();
+    let n = body.find("\r\n\r\n").unwrap() + 4;
+
+    assert_eq!(&body[n..], "B\r\nfoo bar baz\r\n0\r\n\r\n");
+}
+
+#[test]
+fn get_chunked_response_with_ka() {
+    let foo_bar = b"foo bar baz";
+    let foo_bar_chunk = b"\r\nfoo bar baz\r\n0\r\n\r\n";
+    let server = serve();
+    server.reply()
+        .status(hyper::Ok)
+        .header(hyper::header::TransferEncoding::chunked())
+        .body(foo_bar);
+    let mut req = connect(server.addr());
+    req.write_all(b"\
+        GET / HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Connection: keep-alive\r\n\
+        \r\n\
+    ").expect("writing 1");
+
+    let mut buf = [0; 1024 * 4];
+    let mut ntotal = 0;
+    loop {
+        let n = req.read(&mut buf[ntotal..]).expect("reading 1");
+        ntotal = ntotal + n;
+        assert!(ntotal < buf.len());
+        if &buf[ntotal - foo_bar_chunk.len()..ntotal] == foo_bar_chunk {
+            break;
+        }
+    }
+
+
+    // try again!
+
+    let quux = b"zar quux";
+    server.reply()
+        .status(hyper::Ok)
+        .header(hyper::header::ContentLength(quux.len() as u64))
+        .body(quux);
+    req.write_all(b"\
+        GET /quux HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Connection: close\r\n\
+        \r\n\
+    ").expect("writing 2");
+
+    let mut buf = [0; 1024 * 8];
+    loop {
+        let n = req.read(&mut buf[..]).expect("reading 2");
+        assert!(n > 0, "n = {}", n);
+        if n < buf.len() && n > 0  {
+            if &buf[n - quux.len()..n] == quux {
+                break;
+            }
+        }
+    }
+}
+
+#[test]
+fn post_with_chunked_body() {
+    let server = serve();
+    let mut req = connect(server.addr());
+    req.write_all(b"\
+        POST / HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Transfer-Encoding: chunked\r\n\
+        \r\n\
+        1\r\n\
+        q\r\n\
+        2\r\n\
+        we\r\n\
+        2\r\n\
+        rt\r\n\
+        0\r\n\
+        \r\n\
+    ").unwrap();
+    req.read(&mut [0; 256]).unwrap();
+
+    assert_eq!(server.body(), b"qwert");
+}
+
+#[test]
+fn empty_response_chunked() {
+    let server = serve();
+
+    server.reply()
+        .status(hyper::Ok)
+        .body("");
+
+    let mut req = connect(server.addr());
+    req.write_all(b"\
+        GET / HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Content-Length: 0\r\n\
+        Connection: close\r\n\
+        \r\n\
+    ").unwrap();
+
+
+    let mut response = String::new();
+    req.read_to_string(&mut response).unwrap();
+
+    assert!(response.contains("Transfer-Encoding: chunked\r\n"));
+
+    let mut lines = response.lines();
+    assert_eq!(lines.next(), Some("HTTP/1.1 200 OK"));
+
+    let mut lines = lines.skip_while(|line| !line.is_empty());
+    assert_eq!(lines.next(), Some(""));
+    // 0\r\n\r\n
+    assert_eq!(lines.next(), Some("0"));
+    assert_eq!(lines.next(), Some(""));
+    assert_eq!(lines.next(), None);
+}
+
+#[test]
+fn empty_response_chunked_without_body_should_set_content_length() {
+    extern crate pretty_env_logger;
+    let _ = pretty_env_logger::init();
+    let server = serve();
+    server.reply()
+        .status(hyper::Ok)
+        .header(hyper::header::TransferEncoding::chunked());
+    let mut req = connect(server.addr());
+    req.write_all(b"\
+        GET / HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Connection: close\r\n\
+        \r\n\
+    ").unwrap();
+
+    let mut response = String::new();
+    req.read_to_string(&mut response).unwrap();
+
+    assert!(!response.contains("Transfer-Encoding: chunked\r\n"));
+    assert!(response.contains("Content-Length: 0\r\n"));
+
+    let mut lines = response.lines();
+    assert_eq!(lines.next(), Some("HTTP/1.1 200 OK"));
+
+    let mut lines = lines.skip_while(|line| !line.is_empty());
+    assert_eq!(lines.next(), Some(""));
+    assert_eq!(lines.next(), None);
+}
+
+#[test]
+fn head_response_can_send_content_length() {
+    extern crate pretty_env_logger;
+    let _ = pretty_env_logger::init();
+    let server = serve();
+    server.reply()
+        .status(hyper::Ok)
+        .header(hyper::header::ContentLength(1024));
+    let mut req = connect(server.addr());
+    req.write_all(b"\
+        HEAD / HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Connection: close\r\n\
+        \r\n\
+    ").unwrap();
+
+    let mut response = String::new();
+    req.read_to_string(&mut response).unwrap();
+
+    assert!(response.contains("Content-Length: 1024\r\n"));
+
+    let mut lines = response.lines();
+    assert_eq!(lines.next(), Some("HTTP/1.1 200 OK"));
+
+    let mut lines = lines.skip_while(|line| !line.is_empty());
+    assert_eq!(lines.next(), Some(""));
+    assert_eq!(lines.next(), None);
+}
+
+#[test]
+fn response_does_not_set_chunked_if_body_not_allowed() {
+    extern crate pretty_env_logger;
+    let _ = pretty_env_logger::init();
+    let server = serve();
+    server.reply()
+        .status(hyper::StatusCode::NotModified)
+        .header(hyper::header::TransferEncoding::chunked());
+    let mut req = connect(server.addr());
+    req.write_all(b"\
+        GET / HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Connection: close\r\n\
+        \r\n\
+    ").unwrap();
+
+    let mut response = String::new();
+    req.read_to_string(&mut response).unwrap();
+
+    assert!(!response.contains("Transfer-Encoding"));
+
+    let mut lines = response.lines();
+    assert_eq!(lines.next(), Some("HTTP/1.1 304 Not Modified"));
+
+    // no body or 0\r\n\r\n
+    let mut lines = lines.skip_while(|line| !line.is_empty());
+    assert_eq!(lines.next(), Some(""));
+    assert_eq!(lines.next(), None);
+}
+
+#[test]
+fn keep_alive() {
+    let foo_bar = b"foo bar baz";
+    let server = serve();
+    server.reply()
+        .status(hyper::Ok)
+        .header(hyper::header::ContentLength(foo_bar.len() as u64))
+        .body(foo_bar);
+    let mut req = connect(server.addr());
+    req.write_all(b"\
+        GET / HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Connection: keep-alive\r\n\
+        \r\n\
+    ").expect("writing 1");
+
+    let mut buf = [0; 1024 * 8];
+    loop {
+        let n = req.read(&mut buf[..]).expect("reading 1");
+        if n < buf.len() {
+            if &buf[n - foo_bar.len()..n] == foo_bar {
+                break;
+            } else {
+            }
+        }
+    }
+
+    // try again!
+
+    let quux = b"zar quux";
+    server.reply()
+        .status(hyper::Ok)
+        .header(hyper::header::ContentLength(quux.len() as u64))
+        .body(quux);
+    req.write_all(b"\
+        GET /quux HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Connection: close\r\n\
+        \r\n\
+    ").expect("writing 2");
+
+    let mut buf = [0; 1024 * 8];
+    loop {
+        let n = req.read(&mut buf[..]).expect("reading 2");
+        assert!(n > 0, "n = {}", n);
+        if n < buf.len() {
+            if &buf[n - quux.len()..n] == quux {
+                break;
+            }
+        }
+    }
+}
+
+#[test]
+fn disable_keep_alive() {
+    let foo_bar = b"foo bar baz";
+    let server = serve_with_options(ServeOptions {
+        keep_alive_disabled: true,
+        .. Default::default()
+    });
+    server.reply()
+        .status(hyper::Ok)
+        .header(hyper::header::ContentLength(foo_bar.len() as u64))
+        .body(foo_bar);
+    let mut req = connect(server.addr());
+    req.write_all(b"\
+        GET / HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Connection: keep-alive\r\n\
+        \r\n\
+    ").expect("writing 1");
+
+    let mut buf = [0; 1024 * 8];
+    loop {
+        let n = req.read(&mut buf[..]).expect("reading 1");
+        if n < buf.len() {
+            if &buf[n - foo_bar.len()..n] == foo_bar {
+                break;
+            } else {
+            }
+        }
+    }
+
+    // try again!
+
+    let quux = b"zar quux";
+    server.reply()
+        .status(hyper::Ok)
+        .header(hyper::header::ContentLength(quux.len() as u64))
+        .body(quux);
+
+    let _ = req.write_all(b"\
+        GET /quux HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Connection: close\r\n\
+        \r\n\
+    ");
+
+    // the write can possibly succeed, since it fills the kernel buffer on the first write
+    let mut buf = [0; 1024 * 8];
+    match req.read(&mut buf[..]) {
+        // Ok(0) means EOF, so a proper shutdown
+        // Err(_) could mean ConnReset or something, also fine
+        Ok(0) |
+        Err(_) => {}
+        Ok(n) => {
+            panic!("read {} bytes on a disabled keep-alive socket", n);
+        }
+    }
+}
+
+#[test]
+fn expect_continue() {
+    let server = serve();
+    let mut req = connect(server.addr());
+    server.reply().status(hyper::Ok);
+
+    req.write_all(b"\
+        POST /foo HTTP/1.1\r\n\
+        Host: example.domain\r\n\
+        Expect: 100-continue\r\n\
+        Content-Length: 5\r\n\
+        Connection: Close\r\n\
+        \r\n\
+    ").expect("write 1");
+
+    let msg = b"HTTP/1.1 100 Continue\r\n\r\n";
+    let mut buf = vec![0; msg.len()];
+    req.read_exact(&mut buf).expect("read 1");
+    assert_eq!(buf, msg);
+
+    let msg = b"hello";
+    req.write_all(msg).expect("write 2");
+
+    let mut body = String::new();
+    req.read_to_string(&mut body).expect("read 2");
+
+    let body = server.body();
+    assert_eq!(body, msg);
+}
+
+// -------------------------------------------------
+// the Server that is used to run all the tests with
+// -------------------------------------------------
+
 struct Serve {
     addr: SocketAddr,
     msg_rx: mpsc::Receiver<Msg>,
@@ -190,366 +615,4 @@ fn serve_with_options(options: ServeOptions) -> Serve {
     }
 }
 
-#[test]
-fn server_get_should_ignore_body() {
-    let server = serve();
 
-    let mut req = connect(server.addr());
-    // Connection: close = don't try to parse the body as a new request
-    req.write_all(b"\
-        GET / HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Connection: close\r\n\
-        \r\n\
-        I shouldn't be read.\r\n\
-    ").unwrap();
-    req.read(&mut [0; 256]).unwrap();
-
-    assert_eq!(server.body(), b"");
-}
-
-#[test]
-fn server_get_with_body() {
-    let server = serve();
-    let mut req = connect(server.addr());
-    req.write_all(b"\
-        GET / HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Content-Length: 19\r\n\
-        \r\n\
-        I'm a good request.\r\n\
-    ").unwrap();
-    req.read(&mut [0; 256]).unwrap();
-
-    // note: doesn't include trailing \r\n, cause Content-Length wasn't 21
-    assert_eq!(server.body(), b"I'm a good request.");
-}
-
-#[test]
-fn server_get_fixed_response() {
-    let foo_bar = b"foo bar baz";
-    let server = serve();
-    server.reply()
-        .status(hyper::Ok)
-        .header(hyper::header::ContentLength(foo_bar.len() as u64))
-        .body(foo_bar);
-    let mut req = connect(server.addr());
-    req.write_all(b"\
-        GET / HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Connection: close\r\n\
-        \r\n\
-    ").unwrap();
-    let mut body = String::new();
-    req.read_to_string(&mut body).unwrap();
-    let n = body.find("\r\n\r\n").unwrap() + 4;
-
-    assert_eq!(&body[n..], "foo bar baz");
-}
-
-#[test]
-fn server_get_chunked_response() {
-    let foo_bar = b"foo bar baz";
-    let server = serve();
-    server.reply()
-        .status(hyper::Ok)
-        .header(hyper::header::TransferEncoding::chunked())
-        .body(foo_bar);
-    let mut req = connect(server.addr());
-    req.write_all(b"\
-        GET / HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Connection: close\r\n\
-        \r\n\
-    ").unwrap();
-    let mut body = String::new();
-    req.read_to_string(&mut body).unwrap();
-    let n = body.find("\r\n\r\n").unwrap() + 4;
-
-    assert_eq!(&body[n..], "B\r\nfoo bar baz\r\n0\r\n\r\n");
-}
-
-#[test]
-fn server_get_chunked_response_with_ka() {
-    let foo_bar = b"foo bar baz";
-    let foo_bar_chunk = b"\r\nfoo bar baz\r\n0\r\n\r\n";
-    let server = serve();
-    server.reply()
-        .status(hyper::Ok)
-        .header(hyper::header::TransferEncoding::chunked())
-        .body(foo_bar);
-    let mut req = connect(server.addr());
-    req.write_all(b"\
-        GET / HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Connection: keep-alive\r\n\
-        \r\n\
-    ").expect("writing 1");
-
-    let mut buf = [0; 1024 * 4];
-    let mut ntotal = 0;
-    loop {
-        let n = req.read(&mut buf[ntotal..]).expect("reading 1");
-        ntotal = ntotal + n;
-        assert!(ntotal < buf.len());
-        if &buf[ntotal - foo_bar_chunk.len()..ntotal] == foo_bar_chunk {
-            break;
-        }
-    }
-
-
-    // try again!
-
-    let quux = b"zar quux";
-    server.reply()
-        .status(hyper::Ok)
-        .header(hyper::header::ContentLength(quux.len() as u64))
-        .body(quux);
-    req.write_all(b"\
-        GET /quux HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Connection: close\r\n\
-        \r\n\
-    ").expect("writing 2");
-
-    let mut buf = [0; 1024 * 8];
-    loop {
-        let n = req.read(&mut buf[..]).expect("reading 2");
-        assert!(n > 0, "n = {}", n);
-        if n < buf.len() && n > 0  {
-            if &buf[n - quux.len()..n] == quux {
-                break;
-            }
-        }
-    }
-}
-
-
-
-#[test]
-fn server_post_with_chunked_body() {
-    let server = serve();
-    let mut req = connect(server.addr());
-    req.write_all(b"\
-        POST / HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Transfer-Encoding: chunked\r\n\
-        \r\n\
-        1\r\n\
-        q\r\n\
-        2\r\n\
-        we\r\n\
-        2\r\n\
-        rt\r\n\
-        0\r\n\
-        \r\n\
-    ").unwrap();
-    req.read(&mut [0; 256]).unwrap();
-
-    assert_eq!(server.body(), b"qwert");
-}
-
-#[test]
-fn server_empty_response_chunked() {
-    let server = serve();
-
-    server.reply()
-        .status(hyper::Ok)
-        .body("");
-
-    let mut req = connect(server.addr());
-    req.write_all(b"\
-        GET / HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Content-Length: 0\r\n\
-        Connection: close\r\n\
-        \r\n\
-    ").unwrap();
-
-
-    let mut response = String::new();
-    req.read_to_string(&mut response).unwrap();
-
-    assert!(response.contains("Transfer-Encoding: chunked\r\n"));
-
-    let mut lines = response.lines();
-    assert_eq!(lines.next(), Some("HTTP/1.1 200 OK"));
-
-    let mut lines = lines.skip_while(|line| !line.is_empty());
-    assert_eq!(lines.next(), Some(""));
-    // 0\r\n\r\n
-    assert_eq!(lines.next(), Some("0"));
-    assert_eq!(lines.next(), Some(""));
-    assert_eq!(lines.next(), None);
-}
-
-#[test]
-fn server_empty_response_chunked_without_body_should_set_content_length() {
-    extern crate pretty_env_logger;
-    let _ = pretty_env_logger::init();
-    let server = serve();
-    server.reply()
-        .status(hyper::Ok)
-        .header(hyper::header::TransferEncoding::chunked());
-    let mut req = connect(server.addr());
-    req.write_all(b"\
-        GET / HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Connection: close\r\n\
-        \r\n\
-    ").unwrap();
-
-    let mut response = String::new();
-    req.read_to_string(&mut response).unwrap();
-
-    assert!(!response.contains("Transfer-Encoding: chunked\r\n"));
-    assert!(response.contains("Content-Length: 0\r\n"));
-
-    let mut lines = response.lines();
-    assert_eq!(lines.next(), Some("HTTP/1.1 200 OK"));
-
-    let mut lines = lines.skip_while(|line| !line.is_empty());
-    assert_eq!(lines.next(), Some(""));
-    assert_eq!(lines.next(), None);
-}
-
-#[test]
-fn server_keep_alive() {
-    let foo_bar = b"foo bar baz";
-    let server = serve();
-    server.reply()
-        .status(hyper::Ok)
-        .header(hyper::header::ContentLength(foo_bar.len() as u64))
-        .body(foo_bar);
-    let mut req = connect(server.addr());
-    req.write_all(b"\
-        GET / HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Connection: keep-alive\r\n\
-        \r\n\
-    ").expect("writing 1");
-
-    let mut buf = [0; 1024 * 8];
-    loop {
-        let n = req.read(&mut buf[..]).expect("reading 1");
-        if n < buf.len() {
-            if &buf[n - foo_bar.len()..n] == foo_bar {
-                break;
-            } else {
-            }
-        }
-    }
-
-    // try again!
-
-    let quux = b"zar quux";
-    server.reply()
-        .status(hyper::Ok)
-        .header(hyper::header::ContentLength(quux.len() as u64))
-        .body(quux);
-    req.write_all(b"\
-        GET /quux HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Connection: close\r\n\
-        \r\n\
-    ").expect("writing 2");
-
-    let mut buf = [0; 1024 * 8];
-    loop {
-        let n = req.read(&mut buf[..]).expect("reading 2");
-        assert!(n > 0, "n = {}", n);
-        if n < buf.len() {
-            if &buf[n - quux.len()..n] == quux {
-                break;
-            }
-        }
-    }
-}
-
-#[test]
-fn test_server_disable_keep_alive() {
-  let foo_bar = b"foo bar baz";
-    let server = serve_with_options(ServeOptions {
-        keep_alive_disabled: true,
-        .. Default::default()
-    });
-    server.reply()
-        .status(hyper::Ok)
-        .header(hyper::header::ContentLength(foo_bar.len() as u64))
-        .body(foo_bar);
-    let mut req = connect(server.addr());
-    req.write_all(b"\
-        GET / HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Connection: keep-alive\r\n\
-        \r\n\
-    ").expect("writing 1");
-
-    let mut buf = [0; 1024 * 8];
-    loop {
-        let n = req.read(&mut buf[..]).expect("reading 1");
-        if n < buf.len() {
-            if &buf[n - foo_bar.len()..n] == foo_bar {
-                break;
-            } else {
-            }
-        }
-    }
-
-    // try again!
-
-    let quux = b"zar quux";
-    server.reply()
-        .status(hyper::Ok)
-        .header(hyper::header::ContentLength(quux.len() as u64))
-        .body(quux);
-
-    let _ = req.write_all(b"\
-        GET /quux HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Connection: close\r\n\
-        \r\n\
-    ");
-
-    // the write can possibly succeed, since it fills the kernel buffer on the first write
-    let mut buf = [0; 1024 * 8];
-    match req.read(&mut buf[..]) {
-        // Ok(0) means EOF, so a proper shutdown
-        // Err(_) could mean ConnReset or something, also fine
-        Ok(0) |
-        Err(_) => {}
-        Ok(n) => {
-            panic!("read {} bytes on a disabled keep-alive socket", n);
-        }
-    }
-}
-
-#[test]
-fn expect_continue() {
-    let server = serve();
-    let mut req = connect(server.addr());
-    server.reply().status(hyper::Ok);
-
-    req.write_all(b"\
-        POST /foo HTTP/1.1\r\n\
-        Host: example.domain\r\n\
-        Expect: 100-continue\r\n\
-        Content-Length: 5\r\n\
-        Connection: Close\r\n\
-        \r\n\
-    ").expect("write 1");
-
-    let msg = b"HTTP/1.1 100 Continue\r\n\r\n";
-    let mut buf = vec![0; msg.len()];
-    req.read_exact(&mut buf).expect("read 1");
-    assert_eq!(buf, msg);
-
-    let msg = b"hello";
-    req.write_all(msg).expect("write 2");
-
-    let mut body = String::new();
-    req.read_to_string(&mut body).expect("read 2");
-
-    let body = server.body();
-    assert_eq!(body, msg);
-}