use std::cell::{Cell, RefCell};
use std::{marker::PhantomData, num::NonZeroU16, rc::Rc, task::Context};
use ntex_service::{Pipeline, Service, ServiceCtx};
use ntex_util::future::{Either, join};
use ntex_util::{HashSet, services::inflight::InFlightService};
use crate::error::{DispatcherError, PayloadError, ProtocolError, SpecViolation};
use crate::v3::codec::{self, Decoded, Encoded, Packet};
use crate::v3::shared::{Ack, MqttShared};
use crate::v3::{control::ProtocolMessageKind, publish::Publish};
use crate::{payload::Payload, payload::PayloadStatus, payload::PlSender};
use super::control::{ProtocolMessage, ProtocolMessageAck};
pub(super) fn create_dispatcher<T, C, E>(
sink: Rc<MqttShared>,
inflight: usize,
max_buffer_size: usize,
publish: T,
control: C,
) -> impl Service<Decoded, Response = Option<Encoded>, Error = DispatcherError<E>>
where
E: 'static,
T: Service<Publish, Response = Either<(), Publish>, Error = E> + 'static,
C: Service<ProtocolMessage, Response = ProtocolMessageAck, Error = E> + 'static,
{
InFlightService::new(
inflight,
Dispatcher::new(
sink,
publish,
control.map_err(DispatcherError::Service),
max_buffer_size,
),
)
}
pub(crate) struct Dispatcher<T, C, E> {
publish: T,
inner: Rc<Inner<C>>,
max_buffer_size: usize,
_t: PhantomData<E>,
}
struct Inner<C> {
control: Pipeline<C>,
sink: Rc<MqttShared>,
payload: Cell<Option<PlSender>>,
inflight: RefCell<HashSet<NonZeroU16>>,
}
impl<T, C, E> Dispatcher<T, C, E>
where
T: Service<Publish, Response = Either<(), Publish>, Error = E>,
C: Service<ProtocolMessage, Response = ProtocolMessageAck, Error = DispatcherError<E>>,
{
pub(crate) fn new(
sink: Rc<MqttShared>,
publish: T,
control: C,
max_buffer_size: usize,
) -> Self {
Self {
publish,
max_buffer_size,
inner: Rc::new(Inner {
sink,
payload: Cell::new(None),
control: Pipeline::new(control),
inflight: RefCell::new(HashSet::default()),
}),
_t: PhantomData,
}
}
}
impl<C> Inner<C> {
fn drop_payload<PErr>(&self, err: &PErr)
where
PErr: Clone,
PayloadError: From<PErr>,
{
if let Some(pl) = self.payload.take() {
pl.set_error(err.clone().into());
}
}
}
impl<T, C, E> Service<Decoded> for Dispatcher<T, C, E>
where
T: Service<Publish, Response = Either<(), Publish>, Error = E> + 'static,
C: Service<ProtocolMessage, Response = ProtocolMessageAck, Error = DispatcherError<E>>
+ 'static,
E: 'static,
{
type Response = Option<Encoded>;
type Error = DispatcherError<E>;
#[inline]
async fn ready(&self, ctx: ServiceCtx<'_, Self>) -> Result<(), Self::Error> {
let (res1, res2) = join(ctx.ready(&self.publish), self.inner.control.ready()).await;
if (res1.is_err() || res2.is_err())
&& let Some(pl) = self.inner.payload.take()
{
self.inner.payload.set(Some(pl.clone()));
if pl.ready().await != PayloadStatus::Ready {
self.inner.sink.force_close();
}
}
res1.map_err(DispatcherError::Service)?;
res2?;
Ok(())
}
fn poll(&self, cx: &mut Context<'_>) -> Result<(), Self::Error> {
self.publish.poll(cx).map_err(DispatcherError::Service)?;
self.inner.control.poll(cx)
}
async fn shutdown(&self) {
self.inner.drop_payload(&PayloadError::Disconnected);
self.inner.sink.close();
self.publish.shutdown().await;
self.inner.control.shutdown().await;
}
#[allow(clippy::too_many_lines)]
async fn call(
&self,
packet: Decoded,
ctx: ServiceCtx<'_, Self>,
) -> Result<Self::Response, Self::Error> {
log::trace!("Dispatch packet: {packet:#?}");
match packet {
Decoded::Publish(publish, payload, size) => {
let inner = self.inner.as_ref();
let packet_id = publish.packet_id;
if let Some(pid) = packet_id
&& !inner.inflight.borrow_mut().insert(pid)
{
log::trace!("Duplicated packet id for publish packet: {pid:?}");
return Err(SpecViolation::PacketId_2_2_1_3_Pub.into());
}
let payload = if publish.payload_size == payload.len() as u32 {
Payload::from_bytes(payload)
} else {
let (pl, sender) = Payload::from_stream(payload, self.max_buffer_size);
self.inner.payload.set(Some(sender));
pl
};
publish_fn(
&self.publish,
Publish::new(publish, payload, size),
packet_id,
inner,
ctx,
)
.await
}
Decoded::PayloadChunk(buf, eof) => {
let pl = self.inner.payload.take().unwrap();
pl.feed_data(buf);
if eof {
pl.feed_eof();
} else {
self.inner.payload.set(Some(pl));
}
Ok(None)
}
Decoded::Packet(Packet::PublishAck { packet_id }, _) => {
if let Err(e) = self.inner.sink.pkt_ack(Ack::Publish(packet_id)) {
Err(e.into())
} else {
Ok(None)
}
}
Decoded::Packet(Packet::PublishReceived { packet_id }, _) => {
if let Err(e) = self.inner.sink.pkt_ack(Ack::Receive(packet_id)) {
Err(e.into())
} else {
Ok(None)
}
}
Decoded::Packet(Packet::PublishComplete { packet_id }, _) => {
if let Err(e) = self.inner.sink.pkt_ack(Ack::Complete(packet_id)) {
Err(e.into())
} else {
Ok(None)
}
}
Decoded::Packet(Packet::PublishRelease { packet_id }, _) => {
if self.inner.inflight.borrow().contains(&packet_id) {
self.inner.control(ProtocolMessage::pubrel(packet_id)).await
} else {
log::warn!("Unknown packet-id in PublishRelease packet");
self.inner.sink.close();
Ok(None)
}
}
Decoded::Packet(Packet::SubscribeAck { packet_id, status }, _) => {
if let Err(e) = self.inner.sink.pkt_ack(Ack::Subscribe { packet_id, status }) {
Err(e.into())
} else {
Ok(None)
}
}
Decoded::Packet(Packet::UnsubscribeAck { packet_id }, _) => {
if let Err(e) = self.inner.sink.pkt_ack(Ack::Unsubscribe(packet_id)) {
Err(e.into())
} else {
Ok(None)
}
}
Decoded::Packet(
pkt @ (Packet::PingRequest
| Packet::Disconnect
| Packet::Subscribe { .. }
| Packet::Unsubscribe { .. }),
_,
) => Err(ProtocolError::unexpected_packet(
pkt.packet_type(),
"Packet of the type is not expected from server",
)
.into()),
Decoded::Packet(pkt, _) => {
log::debug!("Unsupported packet: {pkt:?}");
Ok(None)
}
}
}
}
async fn publish_fn<'f, T, C, E>(
svc: &'f T,
pkt: Publish,
packet_id: Option<NonZeroU16>,
inner: &'f Inner<C>,
ctx: ServiceCtx<'f, Dispatcher<T, C, E>>,
) -> Result<Option<Encoded>, DispatcherError<E>>
where
T: Service<Publish, Response = Either<(), Publish>, Error = E>,
C: Service<ProtocolMessage, Response = ProtocolMessageAck, Error = DispatcherError<E>>,
{
let res = ctx.call(svc, pkt).await.map_err(DispatcherError::Service)?;
match res {
Either::Left(()) => {
log::trace!("Publish result for packet {packet_id:?} is ready");
if let Some(packet_id) = packet_id {
inner.inflight.borrow_mut().remove(&packet_id);
Ok(Some(Encoded::Packet(Packet::PublishAck { packet_id })))
} else {
Ok(None)
}
}
Either::Right(pkt) => {
let (pkt, payload, size) = pkt.into_inner();
inner.control(ProtocolMessage::publish(pkt, payload, size)).await
}
}
}
impl<C> Inner<C> {
async fn control<E>(
&self,
msg: ProtocolMessage,
) -> Result<Option<Encoded>, DispatcherError<E>>
where
C: Service<ProtocolMessage, Response = ProtocolMessageAck, Error = DispatcherError<E>>,
{
let packet = match self
.control
.call(msg)
.await
.inspect_err(|_| {
self.drop_payload(&PayloadError::Service);
self.sink.close();
})?
.result
{
ProtocolMessageKind::Ping => Some(Encoded::Packet(codec::Packet::PingResponse)),
ProtocolMessageKind::PublishAck(id) => {
self.inflight.borrow_mut().remove(&id);
Some(Encoded::Packet(codec::Packet::PublishAck { packet_id: id }))
}
ProtocolMessageKind::PublishRelease(id) => {
self.inflight.borrow_mut().remove(&id);
Some(Encoded::Packet(Packet::PublishComplete { packet_id: id }))
}
ProtocolMessageKind::Subscribe(_) | ProtocolMessageKind::Unsubscribe(_) => {
unreachable!()
}
ProtocolMessageKind::Disconnect => {
self.drop_payload(&PayloadError::Service);
self.sink.close();
None
}
ProtocolMessageKind::Nothing => None,
};
Ok(packet)
}
}
#[cfg(test)]
mod tests {
use std::{future::Future, pin::Pin};
use ntex_bytes::{ByteString, Bytes};
use ntex_io::{Io, testing::IoTest};
use ntex_service::{cfg::SharedCfg, fn_service};
use ntex_util::future::{Ready, lazy};
use ntex_util::time::{Seconds, sleep};
use super::*;
use crate::v3::{QoS, codec::Decoded};
#[ntex::test]
async fn test_dup_packet_id() {
let io = Io::new(IoTest::create().0, SharedCfg::new("DBG"));
let codec = codec::Codec::default();
let shared = Rc::new(MqttShared::new(io.get_ref(), codec, false, Rc::default()));
let disp = Pipeline::new(Dispatcher::<_, _, ()>::new(
shared.clone(),
fn_service(|_| async {
sleep(Seconds(10)).await;
Ok(Either::Left(()))
}),
fn_service(|_| {
Ready::Ok(ProtocolMessageAck { result: ProtocolMessageKind::Nothing })
}),
32 * 1024,
));
let mut f: Pin<Box<dyn Future<Output = Result<_, _>>>> =
Box::pin(disp.call(Decoded::Publish(
codec::Publish {
dup: false,
retain: false,
qos: QoS::AtLeastOnce,
topic: ByteString::new(),
packet_id: NonZeroU16::new(1),
payload_size: 0,
},
Bytes::new(),
999,
)));
let _ = lazy(|cx| Pin::new(&mut f).poll(cx)).await;
let f = Box::pin(disp.call(Decoded::Publish(
codec::Publish {
dup: false,
retain: false,
qos: QoS::AtLeastOnce,
topic: ByteString::new(),
packet_id: NonZeroU16::new(1),
payload_size: 0,
},
Bytes::new(),
999,
)));
let err = f.await.err().unwrap();
match err {
DispatcherError::Protocol(msg) => {
assert!(
format!("{msg}")
.contains("PUBLISH received with packet id that is already in use")
);
}
DispatcherError::Service(()) => panic!(),
}
}
}