Add extension read and write traits

`tokio::io` has the handy AsyncReadExt and AsyncWriteExt traits, which
were preivously used in tests.

Now that we rely on Hyper IO, those had to be ported over.
That is done in this PR.

- AsyncReadExt -> ReadExt
- AsyncWriteExt -> WriteExt
- tokio internal Read -> ReadFut
- tokio internal Write -> WriteFut

The read timeout test is failing. I think it has to do with the `impl
Future` for `ReadFut`.

Cargo.toml

@@ -22,3 +22,4 @@ tokio = { version = "1.0.0", features = ["io-std", "io-util", "macros"] }
 hyper = { version = "1.0", features = ["http1"] }
 hyper-tls = "0.6"
 http-body-util = "0.1"
+tokio-util = { version = "0.7", features = ["io"] }

src/lib.rs

@@ -4,10 +4,11 @@ use std::pin::Pin;
 use std::task::{Context, Poll};
 use std::time::Duration;
 
+use hyper::rt::{Read, Write};
 use tokio::time::timeout;
 
-use hyper_util::client::legacy::connect::{Connected, Connection};
 use hyper::Uri;
+use hyper_util::client::legacy::connect::{Connected, Connection};
 use tower_service::Service;
 
 mod stream;
@@ -31,8 +32,8 @@ pub struct TimeoutConnector<T> {
 impl<T> TimeoutConnector<T>
 where
     T: Service<Uri> + Send,
-    T::Response: hyper::rt::Read + hyper::rt::Write + Send + Unpin,
-    T::Future: Send + 'static,  
+    T::Response: Read + Write + Send + Unpin,
+    T::Future: Send + 'static,
     T::Error: Into<BoxError>,
 {
     /// Construct a new TimeoutConnector with a given connector implementing the `Connect` trait
@@ -67,7 +68,7 @@ where
         let read_timeout = self.read_timeout;
         let write_timeout = self.write_timeout;
         let connecting = self.connector.call(dst);
-        
+
         let fut = async move {
             let mut stream = match connect_timeout {
                 None => {
@@ -132,12 +133,15 @@ where
 
 #[cfg(test)]
 mod tests {
-    use std::{io, error::Error};
     use std::time::Duration;
+    use std::{error::Error, io};
 
     use http_body_util::Empty;
     use hyper::body::Bytes;
-    use hyper_util::{client::legacy::{connect::HttpConnector, Client}, rt::TokioExecutor};
+    use hyper_util::{
+        client::legacy::{connect::HttpConnector, Client},
+        rt::TokioExecutor,
+    };
 
     use super::TimeoutConnector;
 
@@ -191,85 +195,3 @@ mod tests {
         }
     }
 }
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