commonware-consensus 2026.4.0

Order opaque messages in a Byzantine environment.
Documentation 
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

use crate::{types::Epoch, Monitor as M};
use commonware_utils::{
    channel::{fallible::AsyncFallibleExt, mpsc},
    sync::Mutex,
};
use std::sync::Arc;

struct Inner {
    epoch: Epoch,
    subscribers: Vec<mpsc::Sender<Epoch>>,
}

impl Inner {
    fn new(epoch: Epoch) -> Self {
        Self {
            epoch,
            subscribers: Vec::new(),
        }
    }

    fn update(&mut self, epoch: Epoch) {
        self.epoch = epoch;
        for subscriber in &mut self.subscribers {
            subscriber.try_send_lossy(epoch);
        }
    }

    fn subscribe(&mut self) -> (Epoch, mpsc::Receiver<Epoch>) {
        let (tx, rx) = mpsc::channel(1);
        self.subscribers.push(tx);
        (self.epoch, rx)
    }
}

#[derive(Clone)]
pub struct Monitor {
    inner: Arc<Mutex<Inner>>,
}

impl Monitor {
    pub fn new(epoch: Epoch) -> Self {
        let inner = Inner::new(epoch);
        Self {
            inner: Arc::new(Mutex::new(inner)),
        }
    }

    pub fn update(&self, epoch: Epoch) {
        self.inner.lock().update(epoch);
    }
}

impl M for Monitor {
    type Index = Epoch;

    async fn subscribe(&mut self) -> (Self::Index, mpsc::Receiver<Self::Index>) {
        self.inner.lock().subscribe()
    }
}