Wire in trailers (#34)

Add send and receive trailer support.

examples/client.rs

@@ -1,27 +1,62 @@
 extern crate h2;
 extern crate http;
+extern crate bytes;
 extern crate futures;
 extern crate tokio_io;
 extern crate tokio_core;
 extern crate io_dump;
 extern crate env_logger;
 
+use h2::*;
 use h2::client::Client;
 
 use http::*;
 use futures::*;
+use bytes::*;
 
 use tokio_core::reactor;
 use tokio_core::net::TcpStream;
 
+struct Process {
+    body: Body<Bytes>,
+    trailers: bool,
+}
+
+impl Future for Process {
+    type Item = ();
+    type Error = ConnectionError;
+
+    fn poll(&mut self) -> Poll<(), ConnectionError> {
+        loop {
+            if self.trailers {
+                let trailers = try_ready!(self.body.poll_trailers());
+
+                println!("GOT TRAILERS: {:?}", trailers);
+
+                return Ok(().into());
+            } else {
+                match try_ready!(self.body.poll()) {
+                    Some(chunk) => {
+                        println!("GOT CHUNK = {:?}", chunk);
+                    }
+                    None => {
+                        self.trailers = true;
+                    }
+                }
+            }
+        }
+    }
+}
+
 pub fn main() {
     let _ = env_logger::init();
 
     let mut core = reactor::Core::new().unwrap();;
+    let handle = core.handle();
 
     let tcp = TcpStream::connect(
         &"127.0.0.1:5928".parse().unwrap(),
-        &core.handle());
+        &handle);
 
     let tcp = tcp.then(|res| {
         let tcp = io_dump::Dump::to_stdout(res.unwrap());
@@ -36,11 +71,30 @@ pub fn main() {
             .uri("https://http2.akamai.com/")
             .body(()).unwrap();
 
-        let stream = client.request(request, true).unwrap();
-        client.join(stream.and_then(|response| {
+        let mut trailers = h2::HeaderMap::new();
+        trailers.insert("zomg", "hello".parse().unwrap());
+
+        let mut stream = client.request(request, false).unwrap();
+
+        // send trailers
+        stream.send_trailers(trailers).unwrap();
+
+        // Spawn a task to run the client...
+        handle.spawn(client.map_err(|e| println!("GOT ERR={:?}", e)));
+
+        stream.and_then(|response| {
             println!("GOT RESPONSE: {:?}", response);
-            Ok(())
-        }))
+
+            // Get the body
+            let (_, body) = response.into_parts();
+
+            Process {
+                body,
+                trailers: false,
+            }
+        }).map_err(|e| {
+            println!("GOT ERR={:?}", e);
+        })
     })
     ;