echo.rs

#![feature(async_await, await_macro)]

use std::io;
use std::net::SocketAddr;

use futures::executor;
use futures::io::AsyncReadExt;
use futures::StreamExt;

use romio::{TcpListener, TcpStream};

fn main() {
    let mut listener = TcpListener::bind(&"127.0.0.1:7878".parse().unwrap()).unwrap();
    let incoming = listener.incoming();

    println!("Listening on 127.0.0.1:7878");

    let process_connections = incoming
        .filter_map(async move |s| s.ok()) // filter only Ok(TcpStream)
        .filter_map(async move |s| s.peer_addr().ok().map(|a| (s, a))) // filter only with peer_addr
        .for_each_concurrent(None, async move |(stream, addr)| {
            let result = await!(echo_on(stream, addr));
            drop(result); // I don't care about errors
        });
    executor::block_on(process_connections);
}

async fn echo_on(stream: TcpStream, addr: SocketAddr) -> io::Result<()> {
    println!("Accepting stream from: {}", addr);
    let (mut reader, mut writer) = stream.split();
    await!(reader.copy_into(&mut writer))?;
    println!("Closing stream from: {}", addr);
    Ok(())
}