hyperactor/
checkpoint.rs

1/*
2 * Copyright (c) Meta Platforms, Inc. and affiliates.
3 * All rights reserved.
4 *
5 * This source code is licensed under the BSD-style license found in the
6 * LICENSE file in the root directory of this source tree.
7 */
8
9//! Checkpoint functionality for various objects to save and load states.
10
11use std::fmt::Debug;
12
13use async_trait::async_trait;
14
15use crate::RemoteMessage;
16use crate::mailbox::log::SeqId;
17
18/// Errors that occur during checkpoint operations.
19/// This enum is marked non-exhaustive to allow for extensibility.
20#[derive(thiserror::Error, Debug)]
21#[non_exhaustive]
22pub enum CheckpointError {
23    /// An error occured during saving checkpoints.
24    #[error("save")]
25    Save(#[source] anyhow::Error),
26
27    /// An error occured during loading checkpoints.
28    #[error("load: {0}")]
29    Load(SeqId, #[source] anyhow::Error),
30}
31
32/// [`Checkpoint`] is used to save the state of an instance so that it can be restored later.
33#[async_trait]
34pub trait Checkpointable: Send + Sync + Sized {
35    /// The type of the state that is saved. The state can be serialized and deserialized
36    /// from persistent storage.
37    type State: RemoteMessage;
38
39    /// Saves the current state.
40    async fn save(&self) -> Result<Self::State, CheckpointError>;
41
42    /// Loads the a state to restore the instance.
43    async fn load(state: Self::State) -> Result<Self, CheckpointError>;
44}
hyperactor/checkpoint.rs

hyperactor/
checkpoint.rs
