From 744c7fd1240224da5542f773174a5de1f0cb2628 Mon Sep 17 00:00:00 2001
From: Nathan Torchia <nemasu@gmail.com>
Date: Wed, 8 Jan 2020 16:27:20 +0900
Subject: [PATCH] Added server example

---
 Cargo.toml         |   4 ++
 examples/server.rs | 107 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 111 insertions(+)
 create mode 100644 examples/server.rs

diff --git a/Cargo.toml b/Cargo.toml
index 7a866cc..72ce465 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -87,6 +87,10 @@ required-features = ["async-std-runtime"]
 name = "autobahn-server"
 required-features = ["async-std-runtime"]
 
+[[example]]
+name = "server"
+required-features = ["async-std-runtime"]
+
 [[example]]
 name = "echo-server"
 required-features = ["async-std-runtime"]
diff --git a/examples/server.rs b/examples/server.rs
new file mode 100644
index 0000000..a2c54e0
--- /dev/null
+++ b/examples/server.rs
@@ -0,0 +1,107 @@
+//! A chat server that broadcasts a message to all connections.
+//!
+//! This is a simple line-based server which accepts WebSocket connections,
+//! reads lines from those connections, and broadcasts the lines to all other
+//! connected clients.
+//!
+//! You can test this out by running:
+//!
+//!     cargo run --example server 127.0.0.1:12345
+//!
+//! And then in another window run:
+//!
+//!     cargo run --example client ws://127.0.0.1:12345/
+//!
+//! You can run the second command in multiple windows and then chat between the
+//! two, seeing the messages from the other client as they're received. For all
+//! connected clients they'll all join the same room and see everyone else's
+//! messages.
+
+use std::env;
+use std::io::Error;
+
+use async_std::net::{TcpListener, TcpStream};
+use async_std::task;
+use futures::channel::mpsc::UnboundedSender;
+use futures::stream::SplitStream;
+use futures::{SinkExt, StreamExt};
+use log::*;
+use std::collections::HashMap;
+use std::net::SocketAddr;
+use std::sync::{Arc, Mutex};
+use tungstenite::protocol::Message;
+
+type Tx = UnboundedSender<Message>;
+
+type WsRx = SplitStream<async_tungstenite::WebSocketStream<TcpStream>>;
+
+type PeerMap = Arc<Mutex<HashMap<SocketAddr, Tx>>>;
+
+async fn handle_message(addr: SocketAddr, peer_map: PeerMap, ws_rx: WsRx) {
+    let mut ws_rx = ws_rx;
+    while let Some(msg) = ws_rx.next().await {
+        let msg = msg.expect("Failed to get response");
+        info!(
+            "Received a message from {}: {}",
+            addr,
+            msg.to_text().unwrap()
+        );
+
+        for peer in peer_map.lock().unwrap().iter_mut() {
+            let _ = peer.1.unbounded_send(msg.clone());
+        }
+    }
+}
+
+async fn accept_connection(peer_map: PeerMap, raw_stream: TcpStream) {
+    let addr = raw_stream
+        .peer_addr()
+        .expect("connected streams should have a peer address");
+    info!("Peer address: {}", addr);
+
+    let ws_stream = async_tungstenite::accept_async(raw_stream)
+        .await
+        .expect("Error during the websocket handshake occurred");
+
+    info!("New WebSocket connection: {}", addr);
+
+    let (mut ws_tx, ws_rx) = ws_stream.split();
+    let (msg_tx, mut msg_rx) = futures::channel::mpsc::unbounded();
+
+    //We want to be able to send data to a specific peer, use this tx.
+    peer_map.lock().unwrap().insert(addr, msg_tx);
+
+    //Handle incoming messages
+    task::spawn(handle_message(addr, peer_map.clone(), ws_rx));
+
+    //If msg_rx get's some data, send it on the websocket.
+    while let Some(msg) = msg_rx.next().await {
+        info!("Sending message to {}", addr);
+        ws_tx.send(msg).await.expect("Failed to send request");
+    }
+}
+
+async fn run() -> Result<(), Error> {
+    let _ = env_logger::try_init();
+    let addr = env::args()
+        .nth(1)
+        .unwrap_or_else(|| "127.0.0.1:8080".to_string());
+
+    let hm: HashMap<SocketAddr, Tx> = HashMap::new();
+    let state = PeerMap::new(Mutex::new(hm));
+
+    // Create the event loop and TCP listener we'll accept connections on.
+    let try_socket = TcpListener::bind(&addr).await;
+    let listener = try_socket.expect("Failed to bind");
+    info!("Listening on: {}", addr);
+
+    while let Ok((stream, _)) = listener.accept().await {
+        task::spawn(accept_connection(state.clone(), stream));
+    }
+
+    Ok(())
+}
+
+fn main() -> Result<(), Error> {
+    task::block_on(run())
+}