Document observable states

.github/workflows/ci.yml

@@ -135,6 +135,16 @@ jobs:
         env:
           MIRIFLAGS: -Zmiri-strict-provenance -Zmiri-disable-isolation -Zmiri-num-cpus=4
 
+      - name: Run cargo miri example5 (single-threaded executor)
+        run: cargo miri run --example observables
+        env:
+          MIRIFLAGS: -Zmiri-strict-provenance -Zmiri-disable-isolation -Zmiri-num-cpus=1
+
+      - name: Run cargo miri example5 (multi-threaded executor)
+        run: cargo miri run --example observables
+        env:
+          MIRIFLAGS: -Zmiri-strict-provenance -Zmiri-disable-isolation -Zmiri-num-cpus=4
+
   lints:
     name: Lints
     runs-on: ubuntu-latest

README.md

@@ -49,7 +49,8 @@ The [API] documentation is relatively exhaustive and includes a practical
 overview which should provide all necessary information to get started.
 
 More fleshed out examples can also be found in the dedicated
-[directory](asynchronix/examples).
+[simulator](asynchronix/examples) and [utilities](asynchronix-util/examples)
+directories.
 
 [API]: https://docs.rs/asynchronix
 
@@ -183,4 +184,4 @@ This software is licensed under the [Apache License, Version 2.0](LICENSE-APACHE
 
 Unless you explicitly state otherwise, any contribution intentionally submitted
 for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
-dual licensed as above, without any additional terms or conditions.
+dual licensed as above, without any additional terms or conditions.

asynchronix-util/README.md

@@ -1,3 +1,5 @@
 # Utilities for model-building
 
-TODO: add documentation
+This crate contains utilities used for model and simulation bench development.
+
+

asynchronix-util/examples/observables.rs

@@ -0,0 +1,310 @@
+//! Example: processor with observable states.
+//!
+//! This example demonstrates in particular:
+//!
+//! * the use of observable states,
+//! * state machine with delays.
+//!
+//! ```text
+//!                     ┌───────────┐
+//! Switch ON/OFF ●────►│           ├────► Mode
+//!                     │ Processor │
+//! Process data  ●────►│           ├────► Value
+//!                     │           │
+//!                     │           ├────► House Keeping
+//!                     └───────────┘
+//! ```
+
+use std::time::Duration;
+
+use asynchronix::model::{Context, InitializedModel, Model};
+use asynchronix::ports::{EventBuffer, Output};
+use asynchronix::simulation::{AutoActionKey, Mailbox, SimInit, SimulationError};
+use asynchronix::time::MonotonicTime;
+use asynchronix_util::observables::{Observable, ObservableState, ObservableValue};
+
+/// House keeping TM.
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub struct Hk {
+    pub voltage: f64,
+    pub current: f64,
+}
+
+impl Default for Hk {
+    fn default() -> Self {
+        Self {
+            voltage: 0.0,
+            current: 0.0,
+        }
+    }
+}
+
+/// Processor mode ID.
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub enum ModeId {
+    Off,
+    Idle,
+    Processing,
+}
+
+/// Processor state.
+pub enum State {
+    Off,
+    Idle,
+    Processing(AutoActionKey),
+}
+
+impl Default for State {
+    fn default() -> Self {
+        State::Off
+    }
+}
+
+impl Observable<ModeId> for State {
+    fn observe(&self) -> ModeId {
+        match *self {
+            State::Off => ModeId::Off,
+            State::Idle => ModeId::Idle,
+            State::Processing(_) => ModeId::Processing,
+        }
+    }
+}
+
+/// Processor model.
+pub struct Processor {
+    /// Mode output.
+    pub mode: Output<ModeId>,
+
+    /// Calculated value output.
+    pub value: Output<u16>,
+
+    /// HK output.
+    pub hk: Output<Hk>,
+
+    /// Internal state.
+    state: ObservableState<State, ModeId>,
+
+    /// Accumulator.
+    acc: ObservableValue<u16>,
+
+    /// Electrical data.
+    elc: ObservableValue<Hk>,
+}
+
+impl Processor {
+    /// Create a new processor.
+    pub fn new() -> Self {
+        let mode = Output::new();
+        let value = Output::new();
+        let hk = Output::new();
+        Self {
+            mode: mode.clone(),
+            value: value.clone(),
+            hk: hk.clone(),
+            state: ObservableState::new(mode),
+            acc: ObservableValue::new(value),
+            elc: ObservableValue::new(hk),
+        }
+    }
+
+    /// Switch processor ON/OFF.
+    pub async fn switch_power(&mut self, on: bool) {
+        if on {
+            self.state.set(State::Idle).await;
+            self.elc
+                .set(Hk {
+                    voltage: 5.5,
+                    current: 0.1,
+                })
+                .await;
+            self.acc.set(0).await;
+        } else {
+            self.state.set(State::Off).await;
+            self.elc.set(Hk::default()).await;
+            self.acc.set(0).await;
+        }
+    }
+
+    /// Process data for dt milliseconds.
+    pub async fn process(&mut self, dt: u64, context: &Context<Self>) {
+        if matches!(self.state.observe(), ModeId::Idle | ModeId::Processing) {
+            self.state
+                .set(State::Processing(
+                    context
+                        .scheduler
+                        .schedule_keyed_event(
+                            Duration::from_millis(dt),
+                            Self::finish_processing,
+                            (),
+                        )
+                        .unwrap()
+                        .into_auto(),
+                ))
+                .await;
+            self.elc.modify(|hk| hk.current = 1.0).await;
+        }
+    }
+
+    /// Finish processing.
+    async fn finish_processing(&mut self) {
+        self.state.set(State::Idle).await;
+        self.acc.modify(|a| *a += 1).await;
+        self.elc.modify(|hk| hk.current = 0.1).await;
+    }
+}
+
+impl Model for Processor {
+    /// Propagate all internal states.
+    async fn init(mut self, _: &Context<Self>) -> InitializedModel<Self> {
+        self.state.propagate().await;
+        self.acc.propagate().await;
+        self.elc.propagate().await;
+        self.into()
+    }
+}
+
+fn main() -> Result<(), SimulationError> {
+    // ---------------
+    // Bench assembly.
+    // ---------------
+
+    // Models.
+    let mut proc = Processor::new();
+
+    // Mailboxes.
+    let proc_mbox = Mailbox::new();
+
+    // Model handles for simulation.
+    let mut mode = EventBuffer::new();
+    let mut value = EventBuffer::new();
+    let mut hk = EventBuffer::new();
+
+    proc.mode.connect_sink(&mode);
+    proc.value.connect_sink(&value);
+    proc.hk.connect_sink(&hk);
+    let proc_addr = proc_mbox.address();
+
+    // Start time (arbitrary since models do not depend on absolute time).
+    let t0 = MonotonicTime::EPOCH;
+
+    // Assembly and initialization.
+    let mut simu = SimInit::new().add_model(proc, proc_mbox, "proc").init(t0)?;
+
+    // ----------
+    // Simulation.
+    // ----------
+
+    // Initial state.
+    expect(
+        &mut mode,
+        Some(ModeId::Off),
+        &mut value,
+        Some(0),
+        &mut hk,
+        0.0,
+        0.0,
+    );
+
+    // Switch processor on.
+    simu.process_event(Processor::switch_power, true, &proc_addr)?;
+    expect(
+        &mut mode,
+        Some(ModeId::Idle),
+        &mut value,
+        Some(0),
+        &mut hk,
+        5.5,
+        0.1,
+    );
+
+    // Trigger processing.
+    simu.process_event(Processor::process, 100, &proc_addr)?;
+    expect(
+        &mut mode,
+        Some(ModeId::Processing),
+        &mut value,
+        None,
+        &mut hk,
+        5.5,
+        1.0,
+    );
+
+    // All data processed.
+    simu.step_by(Duration::from_millis(101))?;
+    expect(
+        &mut mode,
+        Some(ModeId::Idle),
+        &mut value,
+        Some(1),
+        &mut hk,
+        5.5,
+        0.1,
+    );
+
+    // Trigger long processing.
+    simu.process_event(Processor::process, 100, &proc_addr)?;
+    expect(
+        &mut mode,
+        Some(ModeId::Processing),
+        &mut value,
+        None,
+        &mut hk,
+        5.5,
+        1.0,
+    );
+
+    // Trigger short processing, it cancels the previous one.
+    simu.process_event(Processor::process, 10, &proc_addr)?;
+    expect(
+        &mut mode,
+        Some(ModeId::Processing),
+        &mut value,
+        None,
+        &mut hk,
+        5.5,
+        1.0,
+    );
+
+    // Wait for short processing to finish, check results.
+    simu.step_by(Duration::from_millis(11))?;
+    expect(
+        &mut mode,
+        Some(ModeId::Idle),
+        &mut value,
+        Some(2),
+        &mut hk,
+        5.5,
+        0.1,
+    );
+
+    // Wait long enough, no state change as the long processing has been
+    // cancelled.
+    simu.step_by(Duration::from_millis(100))?;
+    assert_eq!(mode.next(), None);
+    assert_eq!(value.next(), None);
+    assert_eq!(hk.next(), None);
+
+    Ok(())
+}
+
+// Check observable state.
+fn expect(
+    mode: &mut EventBuffer<ModeId>,
+    mode_ex: Option<ModeId>,
+    value: &mut EventBuffer<u16>,
+    value_ex: Option<u16>,
+    hk: &mut EventBuffer<Hk>,
+    voltage_ex: f64,
+    current_ex: f64,
+) {
+    assert_eq!(mode.next(), mode_ex);
+    assert_eq!(value.next(), value_ex);
+    let hk_value = hk.next().unwrap();
+    assert!(same(hk_value.voltage, voltage_ex));
+    assert!(same(hk_value.current, current_ex));
+}
+
+// Compare two voltages or currents.
+fn same(a: f64, b: f64) -> bool {
+    (a - b).abs() < 1e-12
+}

asynchronix-util/src/lib.rs

@@ -1 +1,2 @@
+/// Observable states.
 pub mod observables;

asynchronix-util/src/observables.rs

@@ -1,3 +1,9 @@
+//! Observable states.
+//!
+//! This module contains types used to implement states automatically propagated
+//! to output on change.
+//!
+
 use std::ops::Deref;
 
 use asynchronix::ports::Output;