Update examples to std-future

examples/client.rs

@@ -1,8 +1,14 @@
+#![feature(async_await)]
+
+use futures::{ready, Stream};
 use h2::client;
 use h2::RecvStream;
+use http::{HeaderMap, Request};
+use std::future::Future;
+use std::pin::Pin;
+use std::task::{Context, Poll};
 
-use futures::*;
-use http::*;
+use std::error::Error;
 
 use tokio::net::TcpStream;
 
@@ -12,76 +18,70 @@ struct Process {
 }
 
 impl Future for Process {
-    type Item = ();
-    type Error = h2::Error;
+    type Output = Result<(), h2::Error>;
 
-    fn poll(&mut self) -> Poll<(), h2::Error> {
+    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
         loop {
             if self.trailers {
-                let trailers = try_ready!(self.body.poll_trailers());
+                let trailers = ready!(self.body.poll_trailers(cx));
 
                 println!("GOT TRAILERS: {:?}", trailers);
 
-                return Ok(().into());
+                return Poll::Ready(Ok(()));
             } else {
-                match try_ready!(self.body.poll()) {
-                    Some(chunk) => {
+                match ready!(Pin::new(&mut self.body).poll_next(cx)) {
+                    Some(Ok(chunk)) => {
                         println!("GOT CHUNK = {:?}", chunk);
-                    },
+                    }
+                    Some(Err(e)) => return Poll::Ready(Err(e)),
                     None => {
                         self.trailers = true;
-                    },
+                    }
                 }
             }
         }
     }
 }
 
-pub fn main() {
+#[tokio::main]
+pub async fn main() -> Result<(), Box<dyn Error>> {
     let _ = env_logger::try_init();
 
-    let tcp = TcpStream::connect(&"127.0.0.1:5928".parse().unwrap());
+    let tcp = TcpStream::connect(&"127.0.0.1:5928".parse().unwrap()).await?;
+    let (mut client, h2) = client::handshake(tcp).await?;
 
-    let tcp = tcp.then(|res| {
-        let tcp = res.unwrap();
-        client::handshake(tcp)
-    }).then(|res| {
-            let (mut client, h2) = res.unwrap();
+    println!("sending request");
 
-            println!("sending request");
+    let request = Request::builder()
+        .uri("https://http2.akamai.com/")
+        .body(())
+        .unwrap();
 
-            let request = Request::builder()
-                .uri("https://http2.akamai.com/")
-                .body(())
-                .unwrap();
+    let mut trailers = HeaderMap::new();
+    trailers.insert("zomg", "hello".parse().unwrap());
 
-            let mut trailers = HeaderMap::new();
-            trailers.insert("zomg", "hello".parse().unwrap());
+    let (response, mut stream) = client.send_request(request, false).unwrap();
 
-            let (response, mut stream) = client.send_request(request, false).unwrap();
+    // send trailers
+    stream.send_trailers(trailers).unwrap();
 
-            // send trailers
-            stream.send_trailers(trailers).unwrap();
+    // Spawn a task to run the conn...
+    tokio::spawn(async move {
+        if let Err(e) = h2.await {
+            println!("GOT ERR={:?}", e);
+        }
+    });
 
-            // Spawn a task to run the conn...
-            tokio::spawn(h2.map_err(|e| println!("GOT ERR={:?}", e)));
+    let response = response.await?;
+    println!("GOT RESPONSE: {:?}", response);
 
-            response
-                .and_then(|response| {
-                    println!("GOT RESPONSE: {:?}", response);
+    // Get the body
+    let (_, body) = response.into_parts();
 
-                    // Get the body
-                    let (_, body) = response.into_parts();
-
-                    Process {
-                        body,
-                        trailers: false,
-                    }
-                })
-                .map_err(|e| {
-                    println!("GOT ERR={:?}", e);
-                })
-        });
-
-    tokio::run(tcp);
+    Process {
+        body,
+        trailers: false,
+    }
+    .await?;
+    Ok(())
 }