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mirror of https://github.com/actix/examples synced 2024-11-23 14:31:07 +01:00

remove select macro

This commit is contained in:
Rob Ede 2022-07-12 01:42:58 +01:00
parent 0b93208bb2
commit 25368e6b65
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GPG Key ID: 97C636207D3EF933
5 changed files with 97 additions and 41 deletions

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@ -11,7 +11,7 @@ awc = "3"
derive_more = "0.99.5"
env_logger = "0.9"
futures-util = { version = "0.3.17", default-features = false, features = ["std", "sink"] }
futures-util = { version = "0.3.17", default-features = false, features = ["std"] }
log = "0.4"
rand = "0.8"
tokio = { version = "1.13.1", features = ["rt", "macros", "sync", "time"] }

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@ -1,14 +1,17 @@
use std::time::{Duration, Instant};
use actix_web::rt;
use actix_ws::Message;
use futures_util::stream::StreamExt as _;
use futures_util::{
future::{select, Either},
StreamExt as _,
};
use tokio::{
select,
pin,
sync::{
mpsc::{self, UnboundedSender},
oneshot,
},
time::interval,
};
use crate::{Command, ConnId, RoomId};
@ -31,27 +34,41 @@ pub async fn chat_ws(
let mut name = None;
let mut room = "main".to_owned();
let mut last_heartbeat = Instant::now();
let mut interval = rt::time::interval(HEARTBEAT_INTERVAL);
let mut interval = interval(HEARTBEAT_INTERVAL);
let (conn_tx, mut conn_rx) = mpsc::unbounded_channel();
let (res_tx, res_rx) = oneshot::channel();
// unwrap: chat server is not dropped before the HTTP server
server_tx
.send(Command::Connect { conn_tx, res_tx })
.unwrap();
// unwrap: chat server does not drop our response channel
let conn_id = res_rx.await.unwrap();
loop {
select! {
let close_reason = loop {
// most of the futures we process need to be stack-pinned to work with select()
let tick = interval.tick();
pin!(tick);
let msg_rx = conn_rx.recv();
pin!(msg_rx);
let messages = select(msg_stream.next(), msg_rx);
pin!(messages);
match select(messages, tick).await {
// commands & messages received from client
Some(Ok(msg)) = msg_stream.next() => {
Either::Left((Either::Left((Some(Ok(msg)), _)), _)) => {
log::debug!("msg: {msg:?}");
match msg {
Message::Ping(bytes) => {
last_heartbeat = Instant::now();
let _ = session.pong(&bytes).await;
// unwrap:
session.pong(&bytes).await.unwrap();
}
Message::Pong(_) => {
@ -59,47 +76,64 @@ pub async fn chat_ws(
}
Message::Text(text) => {
process_text_msg(&server_tx, &mut session, &text, conn_id, &mut room, &mut name).await;
process_text_msg(
&server_tx,
&mut session,
&text,
conn_id,
&mut room,
&mut name,
)
.await;
}
Message::Binary(_bin) => {
log::warn!("unexpected binary message");
}
Message::Close(reason) => {
let _ = session.close(reason).await;
break;
}
Message::Close(reason) => break reason,
_ => {
let _ = session.close(None).await;
break;
break None;
}
}
}
// client WebSocket stream error
Either::Left((Either::Left((Some(Err(err)), _)), _)) => {
log::error!("{}", err);
break None;
}
// client WebSocket stream ended
Either::Left((Either::Left((None, _)), _)) => break None,
// chat messages received from other room participants
Some(chat_msg) = conn_rx.recv() => {
Either::Left((Either::Right((Some(chat_msg), _)), _)) => {
session.text(chat_msg).await.unwrap();
}
// heartbeat
_ = interval.tick() => {
// all connection's msg senders were dropped
Either::Left((Either::Right((None, _)), _)) => unreachable!(),
// heartbeat internal tick
Either::Right((_inst, _)) => {
// if no heartbeat ping/pong received recently, close the connection
if Instant::now().duration_since(last_heartbeat) > CLIENT_TIMEOUT {
log::info!("client has not sent heartbeat in over {CLIENT_TIMEOUT:?}; disconnecting");
let _ = session.close(None).await;
break;
log::info!(
"client has not sent heartbeat in over {CLIENT_TIMEOUT:?}; disconnecting"
);
break None;
}
// send heartbeat ping
let _ = session.ping(b"").await;
// reset interval duration
interval.reset();
}
};
}
};
// attempt to close connection gracefully
let _ = session.close(close_reason).await;
}
async fn process_text_msg(
@ -110,12 +144,14 @@ async fn process_text_msg(
room: &mut RoomId,
name: &mut Option<String>,
) {
// strip leading and trailing whitespace (spaces, newlines, etc.)
let msg = text.trim();
// we check for /<cmd> type of messages
if msg.starts_with('/') {
let mut cmd_args = msg.splitn(2, ' ');
// unwrap: we have guaranteed non-zero string length already
match cmd_args.next().unwrap() {
"/list" => {
// Send ListRooms message to chat server and wait for
@ -124,6 +160,7 @@ async fn process_text_msg(
let (res_tx, res_rx) = oneshot::channel();
server_tx.send(Command::List { res_tx }).unwrap();
// unwrap: chat server does not drop our response channel
let rooms = res_rx.await.unwrap();
for room in rooms {
@ -145,6 +182,7 @@ async fn process_text_msg(
})
.unwrap();
// unwrap: chat server does not drop our response channel
res_rx.await.unwrap();
session.text(format!("joined {room_id}")).await.unwrap();
@ -171,6 +209,7 @@ async fn process_text_msg(
}
}
} else {
// prefix message with our name, if assigned
let msg = match name {
Some(ref name) => format!("{name}: {msg}"),
None => msg.to_owned(),
@ -186,8 +225,10 @@ async fn process_text_msg(
skip: conn,
res_tx,
})
// unwrap: chat server is not dropped before the HTTP server
.unwrap();
// unwrap: chat server does not drop our response channel
res_rx.await.unwrap();
}
}

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@ -3,10 +3,12 @@
//! Open `http://localhost:8080/` in browser to test.
use actix_files::NamedFile;
use actix_web::{
middleware, rt, web, App, Error, HttpRequest, HttpResponse, HttpServer, Responder,
use actix_web::{middleware, web, App, Error, HttpRequest, HttpResponse, HttpServer, Responder};
use tokio::{
sync::mpsc::UnboundedSender,
task::{spawn, spawn_local},
try_join,
};
use tokio::sync::mpsc::UnboundedSender;
mod command;
mod handler;
@ -37,7 +39,7 @@ async fn chat_ws(
let (res, session, msg_stream) = actix_ws::handle(&req, stream)?;
// spawn websocket handler (and don't await it) so that the response is returned immediately
rt::spawn(handler::chat_ws((**server_tx).clone(), session, msg_stream));
spawn_local(handler::chat_ws((**server_tx).clone(), session, msg_stream));
Ok(res)
}
@ -51,9 +53,9 @@ async fn main() -> std::io::Result<()> {
let (chat_server, server_tx) = ChatServer::new();
rt::spawn(chat_server.run());
let chat_server = spawn(chat_server.run());
HttpServer::new(move || {
let http_server = HttpServer::new(move || {
App::new()
.app_data(web::Data::new(server_tx.clone()))
// WebSocket UI HTML file
@ -65,6 +67,9 @@ async fn main() -> std::io::Result<()> {
})
.workers(2)
.bind(("127.0.0.1", 8080))?
.run()
.await
.run();
try_join!(http_server, async move { chat_server.await.unwrap() })?;
Ok(())
}

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@ -2,6 +2,7 @@
use std::{
collections::{HashMap, HashSet},
io,
sync::{
atomic::{AtomicUsize, Ordering},
Arc,
@ -62,7 +63,8 @@ impl ChatServer {
for conn_id in sessions {
if *conn_id != skip_id {
if let Some(tx) = self.sessions.get(conn_id) {
tx.send(msg.clone()).unwrap();
// errors if client disconnected abruptly and hasn't been timed-out yet
let _ = tx.send(msg.clone());
}
}
}
@ -152,12 +154,17 @@ impl ChatServer {
self.send_message(&room, "Someone connected", conn_id).await;
}
pub async fn run(mut self) {
pub async fn run(mut self) -> io::Result<()> {
loop {
match self.rx.recv().await.unwrap() {
let cmd = match self.rx.recv().await {
Some(cmd) => cmd,
None => break,
};
match cmd {
Command::Connect { conn_tx, res_tx } => {
let conn_id = self.connect(conn_tx).await;
res_tx.send(conn_id).unwrap();
let _ = res_tx.send(conn_id);
}
Command::Disconnect { conn } => {
@ -165,12 +172,12 @@ impl ChatServer {
}
Command::List { res_tx } => {
res_tx.send(self.list_rooms()).unwrap();
let _ = res_tx.send(self.list_rooms());
}
Command::Join { conn, room, res_tx } => {
self.join_room(conn, room).await;
res_tx.send(()).unwrap();
let _ = res_tx.send(());
}
Command::Message {
@ -180,9 +187,11 @@ impl ChatServer {
res_tx,
} => {
self.send_message(&room, msg, skip).await;
res_tx.send(()).unwrap();
let _ = res_tx.send(());
}
}
}
Ok(())
}
}

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@ -73,6 +73,7 @@ pub async fn echo_heartbeat_ws(
// client WebSocket stream error
Either::Left((Some(Err(err)), _)) => {
log::error!("{}", err);
break None;
}
// client WebSocket stream ended