1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368
use std::{
future::Future,
io, mem,
pin::Pin,
task::{Context, Poll},
thread,
time::Duration,
};
use actix_rt::{time::sleep, System};
use futures_core::{future::BoxFuture, Stream};
use futures_util::stream::StreamExt as _;
use tokio::sync::{mpsc::UnboundedReceiver, oneshot};
use tracing::{error, info};
use crate::{
accept::Accept,
builder::ServerBuilder,
join_all::join_all,
service::InternalServiceFactory,
signals::{SignalKind, Signals},
waker_queue::{WakerInterest, WakerQueue},
worker::{ServerWorker, ServerWorkerConfig, WorkerHandleServer},
ServerHandle,
};
#[derive(Debug)]
pub(crate) enum ServerCommand {
/// Worker failed to accept connection, indicating a probable panic.
///
/// Contains index of faulted worker.
WorkerFaulted(usize),
/// Pause accepting connections.
///
/// Contains return channel to notify caller of successful state change.
Pause(oneshot::Sender<()>),
/// Resume accepting connections.
///
/// Contains return channel to notify caller of successful state change.
Resume(oneshot::Sender<()>),
/// Stop accepting connections and begin shutdown procedure.
Stop {
/// True if shut down should be graceful.
graceful: bool,
/// Return channel to notify caller that shutdown is complete.
completion: Option<oneshot::Sender<()>>,
/// Force System exit when true, overriding `ServerBuilder::system_exit()` if it is false.
force_system_stop: bool,
},
}
/// General purpose TCP server that runs services receiving Tokio `TcpStream`s.
///
/// Handles creating worker threads, restarting faulted workers, connection accepting, and
/// back-pressure logic.
///
/// Creates a worker per CPU core (or the number specified in [`ServerBuilder::workers`]) and
/// distributes connections with a round-robin strategy.
///
/// The [Server] must be awaited or polled in order to start running. It will resolve when the
/// server has fully shut down.
///
/// # Shutdown Signals
/// On UNIX systems, `SIGTERM` will start a graceful shutdown and `SIGQUIT` or `SIGINT` will start a
/// forced shutdown. On Windows, a Ctrl-C signal will start a forced shutdown.
///
/// A graceful shutdown will wait for all workers to stop first.
///
/// # Examples
/// The following is a TCP echo server. Test using `telnet 127.0.0.1 8080`.
///
/// ```no_run
/// use std::io;
///
/// use actix_rt::net::TcpStream;
/// use actix_server::Server;
/// use actix_service::{fn_service, ServiceFactoryExt as _};
/// use bytes::BytesMut;
/// use tokio::io::{AsyncReadExt as _, AsyncWriteExt as _};
///
/// #[actix_rt::main]
/// async fn main() -> io::Result<()> {
/// let bind_addr = ("127.0.0.1", 8080);
///
/// Server::build()
/// .bind("echo", bind_addr, move || {
/// fn_service(move |mut stream: TcpStream| {
/// async move {
/// let mut size = 0;
/// let mut buf = BytesMut::new();
///
/// loop {
/// match stream.read_buf(&mut buf).await {
/// // end of stream; bail from loop
/// Ok(0) => break,
///
/// // write bytes back to stream
/// Ok(bytes_read) => {
/// stream.write_all(&buf[size..]).await.unwrap();
/// size += bytes_read;
/// }
///
/// Err(err) => {
/// eprintln!("Stream Error: {:?}", err);
/// return Err(());
/// }
/// }
/// }
///
/// Ok(())
/// }
/// })
/// .map_err(|err| eprintln!("Service Error: {:?}", err))
/// })?
/// .run()
/// .await
/// }
/// ```
#[must_use = "Server does nothing unless you `.await` or poll it"]
pub struct Server {
handle: ServerHandle,
fut: BoxFuture<'static, io::Result<()>>,
}
impl Server {
/// Create server build.
pub fn build() -> ServerBuilder {
ServerBuilder::default()
}
pub(crate) fn new(builder: ServerBuilder) -> Self {
Server {
handle: ServerHandle::new(builder.cmd_tx.clone()),
fut: Box::pin(ServerInner::run(builder)),
}
}
/// Get a `Server` handle that can be used issue commands and change it's state.
///
/// See [ServerHandle](ServerHandle) for usage.
pub fn handle(&self) -> ServerHandle {
self.handle.clone()
}
}
impl Future for Server {
type Output = io::Result<()>;
#[inline]
fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
Pin::new(&mut Pin::into_inner(self).fut).poll(cx)
}
}
pub struct ServerInner {
worker_handles: Vec<WorkerHandleServer>,
accept_handle: Option<thread::JoinHandle<()>>,
worker_config: ServerWorkerConfig,
services: Vec<Box<dyn InternalServiceFactory>>,
waker_queue: WakerQueue,
system_stop: bool,
stopping: bool,
}
impl ServerInner {
async fn run(builder: ServerBuilder) -> io::Result<()> {
let (mut this, mut mux) = Self::run_sync(builder)?;
while let Some(cmd) = mux.next().await {
this.handle_cmd(cmd).await;
if this.stopping {
break;
}
}
Ok(())
}
fn run_sync(mut builder: ServerBuilder) -> io::Result<(Self, ServerEventMultiplexer)> {
// Give log information on what runtime will be used.
let is_actix = actix_rt::System::try_current().is_some();
let is_tokio = tokio::runtime::Handle::try_current().is_ok();
match (is_actix, is_tokio) {
(true, _) => info!("Actix runtime found; starting in Actix runtime"),
(_, true) => info!("Tokio runtime found; starting in existing Tokio runtime"),
(_, false) => panic!("Actix or Tokio runtime not found; halting"),
}
for (_, name, lst) in &builder.sockets {
info!(
r#"starting service: "{}", workers: {}, listening on: {}"#,
name,
builder.threads,
lst.local_addr()
);
}
let sockets = mem::take(&mut builder.sockets)
.into_iter()
.map(|t| (t.0, t.2))
.collect();
let (waker_queue, worker_handles, accept_handle) = Accept::start(sockets, &builder)?;
let mux = ServerEventMultiplexer {
signal_fut: (builder.listen_os_signals).then(Signals::new),
cmd_rx: builder.cmd_rx,
};
let server = ServerInner {
waker_queue,
accept_handle: Some(accept_handle),
worker_handles,
worker_config: builder.worker_config,
services: builder.factories,
system_stop: builder.exit,
stopping: false,
};
Ok((server, mux))
}
async fn handle_cmd(&mut self, item: ServerCommand) {
match item {
ServerCommand::Pause(tx) => {
self.waker_queue.wake(WakerInterest::Pause);
let _ = tx.send(());
}
ServerCommand::Resume(tx) => {
self.waker_queue.wake(WakerInterest::Resume);
let _ = tx.send(());
}
ServerCommand::Stop {
graceful,
completion,
force_system_stop,
} => {
self.stopping = true;
// Signal accept thread to stop.
// Signal is non-blocking; we wait for thread to stop later.
self.waker_queue.wake(WakerInterest::Stop);
// send stop signal to workers
let workers_stop = self
.worker_handles
.iter()
.map(|worker| worker.stop(graceful))
.collect::<Vec<_>>();
if graceful {
// wait for all workers to shut down
let _ = join_all(workers_stop).await;
}
// wait for accept thread stop
self.accept_handle
.take()
.unwrap()
.join()
.expect("Accept thread must not panic in any case");
if let Some(tx) = completion {
let _ = tx.send(());
}
if self.system_stop || force_system_stop {
sleep(Duration::from_millis(300)).await;
System::try_current().as_ref().map(System::stop);
}
}
ServerCommand::WorkerFaulted(idx) => {
// TODO: maybe just return with warning log if not found ?
assert!(self.worker_handles.iter().any(|wrk| wrk.idx == idx));
error!("worker {} has died; restarting", idx);
let factories = self
.services
.iter()
.map(|service| service.clone_factory())
.collect();
match ServerWorker::start(
idx,
factories,
self.waker_queue.clone(),
self.worker_config,
) {
Ok((handle_accept, handle_server)) => {
*self
.worker_handles
.iter_mut()
.find(|wrk| wrk.idx == idx)
.unwrap() = handle_server;
self.waker_queue.wake(WakerInterest::Worker(handle_accept));
}
Err(err) => error!("can not restart worker {}: {}", idx, err),
};
}
}
}
fn map_signal(signal: SignalKind) -> ServerCommand {
match signal {
SignalKind::Int => {
info!("SIGINT received; starting forced shutdown");
ServerCommand::Stop {
graceful: false,
completion: None,
force_system_stop: true,
}
}
SignalKind::Term => {
info!("SIGTERM received; starting graceful shutdown");
ServerCommand::Stop {
graceful: true,
completion: None,
force_system_stop: true,
}
}
SignalKind::Quit => {
info!("SIGQUIT received; starting forced shutdown");
ServerCommand::Stop {
graceful: false,
completion: None,
force_system_stop: true,
}
}
}
}
}
struct ServerEventMultiplexer {
cmd_rx: UnboundedReceiver<ServerCommand>,
signal_fut: Option<Signals>,
}
impl Stream for ServerEventMultiplexer {
type Item = ServerCommand;
fn poll_next(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
let this = Pin::into_inner(self);
if let Some(signal_fut) = &mut this.signal_fut {
if let Poll::Ready(signal) = Pin::new(signal_fut).poll(cx) {
this.signal_fut = None;
return Poll::Ready(Some(ServerInner::map_signal(signal)));
}
}
this.cmd_rx.poll_recv(cx)
}
}