synaptic_graph/
checkpoint.rs

1use std::collections::HashMap;
2
3use async_trait::async_trait;
4use serde::{Deserialize, Serialize};
5use synaptic_core::SynapseError;
6use tokio::sync::RwLock;
7
8/// Configuration identifying a checkpoint (thread/conversation).
9#[derive(Debug, Clone, Hash, Eq, PartialEq, Serialize, Deserialize)]
10pub struct CheckpointConfig {
11    pub thread_id: String,
12}
13
14impl CheckpointConfig {
15    pub fn new(thread_id: impl Into<String>) -> Self {
16        Self {
17            thread_id: thread_id.into(),
18        }
19    }
20}
21
22/// A snapshot of graph state at a point in execution.
23#[derive(Debug, Clone, Serialize, Deserialize)]
24pub struct Checkpoint {
25    pub state: serde_json::Value,
26    pub next_node: Option<String>,
27}
28
29/// Trait for persisting graph state checkpoints.
30#[async_trait]
31pub trait Checkpointer: Send + Sync {
32    async fn put(
33        &self,
34        config: &CheckpointConfig,
35        checkpoint: &Checkpoint,
36    ) -> Result<(), SynapseError>;
37    async fn get(&self, config: &CheckpointConfig) -> Result<Option<Checkpoint>, SynapseError>;
38    async fn list(&self, config: &CheckpointConfig) -> Result<Vec<Checkpoint>, SynapseError>;
39}
40
41/// In-memory checkpointer (for development/testing).
42#[derive(Default)]
43pub struct MemorySaver {
44    store: RwLock<HashMap<String, Vec<Checkpoint>>>,
45}
46
47impl MemorySaver {
48    pub fn new() -> Self {
49        Self::default()
50    }
51}
52
53#[async_trait]
54impl Checkpointer for MemorySaver {
55    async fn put(
56        &self,
57        config: &CheckpointConfig,
58        checkpoint: &Checkpoint,
59    ) -> Result<(), SynapseError> {
60        let mut store = self.store.write().await;
61        store
62            .entry(config.thread_id.clone())
63            .or_default()
64            .push(checkpoint.clone());
65        Ok(())
66    }
67
68    async fn get(&self, config: &CheckpointConfig) -> Result<Option<Checkpoint>, SynapseError> {
69        let store = self.store.read().await;
70        Ok(store.get(&config.thread_id).and_then(|v| v.last().cloned()))
71    }
72
73    async fn list(&self, config: &CheckpointConfig) -> Result<Vec<Checkpoint>, SynapseError> {
74        let store = self.store.read().await;
75        Ok(store.get(&config.thread_id).cloned().unwrap_or_default())
76    }
77}
synaptic_graph/checkpoint.rs

synaptic_graph/
checkpoint.rs
