modify client to accept connections from a local TCP client

prototypes/quic_demo/src/bin/quic_demo_client.rs

@@ -1,3 +1,7 @@
+use tokio::{
+	net::TcpListener,
+};
+
 use quic_demo::prelude::*;
 
 #[tokio::main]
@@ -15,21 +19,47 @@ async fn main () -> anyhow::Result <()> {
 		..
 	} = endpoint.connect (&server_addr, "localhost")?.await?;
 	
+	debug! ("Waiting for local TCP client to connect to us");
+	
+	let listener = TcpListener::bind ("127.0.0.1:30381").await?;
+	let (tcp_socket, _) = listener.accept ().await?;
+	let (mut local_recv, mut local_send) = tcp_socket.into_split ();
+	
 	debug! ("Connecting to end server");
 	
-	let (mut send, mut recv) = connection.open_bi ().await?;
+	let (mut relay_send, mut relay_recv) = connection.open_bi ().await?;
 	
-	let mut buf = vec! [0u8; 65_536];
-	let mut send_interval = tokio::time::interval (Duration::from_millis (1000));
-	// send_interval.set_missed_tick_behavior (tokio::time::MissedTickBehavior::Skip);
-	loop {
-		send_interval.tick ().await;
+	let uplink_task = tokio::spawn (async move {
+		// Uplink - local client to relay server
 		
-		send.write_all (b"Hi!\n").await?;
-		let bytes_read = recv.read (&mut buf).await?.ok_or_else (|| anyhow::anyhow! ("Server or relay closed connection"))?;
-		let buf_slice = &buf [0..bytes_read];
+		let mut buf = vec! [0u8; 65_536];
+		loop {
+			let bytes_read = local_recv.read (&mut buf).await?;
+			let buf_slice = &buf [0..bytes_read];
+			relay_send.write_all (buf_slice).await?;
+		}
 		
-		let s = std::str::from_utf8 (buf_slice)?;
-		println! ("Received: `{}`", s);
-	}
+		debug! ("Uplink closed");
+		
+		Ok::<_, anyhow::Error> (())
+	});
+	
+	let downlink_task = tokio::spawn (async move {
+		// Downlink - Relay server to local client
+		
+		let mut buf = vec! [0u8; 65_536];
+		while let Some (bytes_read) = relay_recv.read (&mut buf).await? {
+			let buf_slice = &buf [0..bytes_read];
+			local_send.write_all (buf_slice).await?;
+		}
+		
+		debug! ("Downlink closed");
+		
+		Ok::<_, anyhow::Error> (())
+	});
+	
+	uplink_task.await??;
+	downlink_task.await??;
+	
+	Ok (())
 }

prototypes/quic_demo/src/prelude.rs

@@ -3,6 +3,12 @@ pub use std::{
 };
 
 pub use futures_util::StreamExt;
+pub use tokio::{
+	io::{
+		AsyncReadExt,
+		AsyncWriteExt,
+	},
+};
 pub use tracing::{
 	debug,
 	error,