Add SectionRunner events

src/section_runner.rs

@@ -1,7 +1,6 @@
 use crate::model::SectionRef;
 use crate::option_future::OptionFuture;
 use crate::section_interface::SectionInterface;
-use mpsc::error::SendError;
 use std::{
     collections::VecDeque,
     mem::swap,
@@ -14,7 +13,7 @@ use std::{
 use thiserror::Error;
 use tokio::{
     spawn,
-    sync::mpsc,
+    sync::{broadcast, mpsc, oneshot},
     time::{delay_for, Instant},
 };
 use tracing::{debug, trace, trace_span, warn};
@@ -35,7 +34,7 @@ impl SectionRunnerInner {
     }
 }
 
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 enum RunnerMsg {
     Quit,
     QueueRun(RunHandle, SectionRef, Duration),
@@ -43,8 +42,25 @@ enum RunnerMsg {
     CancelAll,
     Pause,
     Unpause,
+    Subscribe(oneshot::Sender<RunnerEventRecv>),
 }
 
+#[derive(Clone, Debug, PartialEq)]
+pub enum RunnerEvent {
+    RunStart(RunHandle),
+    RunFinish(RunHandle),
+    RunPause(RunHandle),
+    RunUnpause(RunHandle),
+    RunCancel(RunHandle),
+    RunnerPause,
+    RunnerUnpause,
+}
+
+pub type RunnerEventRecv = broadcast::Receiver<RunnerEvent>;
+type RunnerEventSend = broadcast::Sender<RunnerEvent>;
+
+const EVENT_CAPACITY: usize = 8;
+
 #[derive(Clone, Debug, PartialEq)]
 enum RunState {
     Waiting,
@@ -95,6 +111,7 @@ struct RunnerTask {
     running: bool,
     delay_future: OptionFuture<tokio::time::Delay>,
     paused: bool,
+    event_send: Option<RunnerEventSend>,
 }
 
 impl RunnerTask {
@@ -108,6 +125,29 @@ impl RunnerTask {
             running: true,
             delay_future: None.into(),
             paused: false,
+            event_send: None,
+        }
+    }
+
+    fn send_event(&mut self, event: RunnerEvent) {
+        if let Some(event_send) = &mut self.event_send {
+            match event_send.send(event) {
+                Ok(_) => {}
+                Err(_closed) => {
+                    self.event_send = None;
+                }
+            }
+        }
+    }
+
+    fn subscribe_event(&mut self) -> RunnerEventRecv {
+        match &mut self.event_send {
+            Some(event_send) => event_send.subscribe(),
+            None => {
+                let (event_send, event_recv) = broadcast::channel(EVENT_CAPACITY);
+                self.event_send = Some(event_send);
+                event_recv
+            }
         }
     }
 
@@ -119,6 +159,7 @@ impl RunnerTask {
         run.state = Running {
             start_time: Instant::now(),
         };
+        self.send_event(RunnerEvent::RunStart(run.handle.clone()));
     }
 
     fn finish_run(&mut self, run: &mut SecRun) {
@@ -127,6 +168,7 @@ impl RunnerTask {
             self.interface
                 .set_section_state(run.section.interface_id, false);
             run.state = RunState::Finished;
+            self.send_event(RunnerEvent::RunFinish(run.handle.clone()));
         } else {
             warn!(
                 section_id = run.section.id,
@@ -143,29 +185,34 @@ impl RunnerTask {
                 .set_section_state(run.section.interface_id, false);
         }
         run.state = RunState::Cancelled;
+        self.send_event(RunnerEvent::RunCancel(run.handle.clone()));
     }
 
     fn pause_run(&mut self, run: &mut SecRun) {
         use RunState::*;
-        match run.state {
+        let new_state = match run.state {
             Running { start_time } => {
                 debug!(section_id = run.section.id, "pausing running section");
                 self.interface
                     .set_section_state(run.section.interface_id, false);
-                run.state = Paused {
+                Paused {
                     start_time,
                     pause_time: Instant::now(),
-                };
+                }
             }
             Waiting => {
                 debug!(section_id = run.section.id, "pausing waiting section");
-                run.state = Paused {
+                Paused {
                     start_time: Instant::now(),
                     pause_time: Instant::now(),
-                };
                 }
-            Finished | Cancelled | Paused { .. } => {}
             }
+            Finished | Cancelled | Paused { .. } => {
+                return;
+            }
+        };
+        run.state = new_state;
+        self.send_event(RunnerEvent::RunPause(run.handle.clone()));
     }
 
     fn unpause_run(&mut self, run: &mut SecRun) {
@@ -183,6 +230,7 @@ impl RunnerTask {
                 };
                 let ran_for = pause_time - start_time;
                 run.duration -= ran_for;
+                self.send_event(RunnerEvent::RunUnpause(run.handle.clone()));
             }
             Waiting | Finished | Cancelled | Running { .. } => {
                 warn!(
@@ -265,9 +313,16 @@ impl RunnerTask {
             }
             Pause => {
                 self.paused = true;
+                self.send_event(RunnerEvent::RunnerPause);
             }
             Unpause => {
                 self.paused = false;
+                self.send_event(RunnerEvent::RunnerUnpause);
+            }
+            Subscribe(res_send) => {
+                let event_recv = self.subscribe_event();
+                // Ignore error if channel closed
+                let _ = res_send.send(event_recv);
             }
         }
     }
@@ -297,8 +352,14 @@ pub struct ChannelClosed;
 
 pub type Result<T, E = ChannelClosed> = std::result::Result<T, E>;
 
-impl<T> From<SendError<T>> for ChannelClosed {
-    fn from(_: SendError<T>) -> Self {
+impl<T> From<mpsc::error::SendError<T>> for ChannelClosed {
+    fn from(_: mpsc::error::SendError<T>) -> Self {
+        Self
+    }
+}
+
+impl From<oneshot::error::RecvError> for ChannelClosed {
+    fn from(_: oneshot::error::RecvError) -> Self {
         Self
     }
 }
@@ -357,6 +418,13 @@ impl SectionRunner {
         self.msg_send.send(RunnerMsg::Unpause).await?;
         Ok(())
     }
+
+    pub async fn subscribe(&mut self) -> Result<RunnerEventRecv> {
+        let (res_send, res_recv) = oneshot::channel();
+        self.msg_send.send(RunnerMsg::Subscribe(res_send)).await?;
+        let event_recv = res_recv.await?;
+        Ok(event_recv)
+    }
 }
 
 #[cfg(test)]
@@ -613,4 +681,84 @@ mod test {
         runner.quit().await.unwrap();
         tokio::task::yield_now().await;
     }
+
+    #[tokio::test]
+    async fn test_event() {
+        let (sections, interface) = make_sections_and_interface();
+        let mut runner = SectionRunner::new(interface.clone());
+
+        let mut event_recv = runner.subscribe().await.unwrap();
+
+        let run1 = runner
+            .queue_run(sections[1].clone(), Duration::from_secs(10))
+            .await
+            .unwrap();
+
+        let run2 = runner
+            .queue_run(sections[0].clone(), Duration::from_secs(10))
+            .await
+            .unwrap();
+
+        let run3 = runner
+            .queue_run(sections[1].clone(), Duration::from_secs(10))
+            .await
+            .unwrap();
+
+        assert_eq!(
+            event_recv.recv().await,
+            Ok(RunnerEvent::RunStart(run1.clone()))
+        );
+
+        runner.pause().await.unwrap();
+        assert_eq!(event_recv.recv().await, Ok(RunnerEvent::RunnerPause));
+        assert_eq!(
+            event_recv.recv().await,
+            Ok(RunnerEvent::RunPause(run1.clone()))
+        );
+
+        runner.unpause().await.unwrap();
+        assert_eq!(event_recv.recv().await, Ok(RunnerEvent::RunnerUnpause));
+        assert_eq!(
+            event_recv.recv().await,
+            Ok(RunnerEvent::RunUnpause(run1.clone()))
+        );
+
+        advance(Duration::from_secs(11)).await;
+        assert_eq!(event_recv.recv().await, Ok(RunnerEvent::RunFinish(run1)));
+        assert_eq!(
+            event_recv.recv().await,
+            Ok(RunnerEvent::RunStart(run2.clone()))
+        );
+
+        runner.pause().await.unwrap();
+        assert_eq!(event_recv.recv().await, Ok(RunnerEvent::RunnerPause));
+        assert_eq!(
+            event_recv.recv().await,
+            Ok(RunnerEvent::RunPause(run2.clone()))
+        );
+
+        // cancel paused run
+        runner.cancel_run(run2.clone()).await.unwrap();
+        assert_eq!(
+            event_recv.recv().await,
+            Ok(RunnerEvent::RunCancel(run2.clone()))
+        );
+        assert_eq!(
+            event_recv.recv().await,
+            Ok(RunnerEvent::RunPause(run3.clone()))
+        );
+
+        runner.unpause().await.unwrap();
+        assert_eq!(event_recv.recv().await, Ok(RunnerEvent::RunnerUnpause));
+        assert_eq!(
+            event_recv.recv().await,
+            Ok(RunnerEvent::RunUnpause(run3.clone()))
+        );
+
+        advance(Duration::from_secs(11)).await;
+        assert_eq!(event_recv.recv().await, Ok(RunnerEvent::RunFinish(run3)));
+
+        runner.quit().await.unwrap();
+        tokio::task::yield_now().await;
+    }
 }