Struct Checkpoint 

pub struct Checkpoint<S> {
    pub id: String,
    pub state: S,
    pub uuid: Uuid,
    pub hash: Hash32,
    pub entries_processed: usize,
    pub context: FoldContext,
    pub fold_version: usize,
    pub created_at: DateTime<Utc>,
}

Generic checkpoint envelope wrapping an arbitrary fold state snapshot.

Carries metadata (ID, timestamp, hash, fold version) alongside the serializable state so consumers can verify and load the correct snapshot.

Fields

id: String

Human-readable checkpoint identifier (e.g. "hnsw_idx:ckpt-1").

state: S

The snapshot state captured at this checkpoint.

uuid: Uuid

Unique identifier for this checkpoint instance.

hash: Hash32

BLAKE3 content hash of the canonical JSON serialization of state.

Computed by CheckpointStore::save and verified by CheckpointStore::load. A mismatch returns FoldError::IntegrityMismatch.

entries_processed: usize

Number of entries processed when this checkpoint was taken.

context: FoldContext

Fold context at checkpoint time.

fold_version: usize

Monotonically increasing fold schema version.

created_at: DateTime<Utc>

Wall-clock time when this checkpoint was created.

Implementations

impl<S: Serialize> Checkpoint<S>

pub fn new( id: impl Into<String>, state: S, uuid: Uuid, entries_processed: usize, context: FoldContext, fold_version: usize, ) -> Result<Self, FoldError>

Create a new checkpoint, computing the BLAKE3 hash of the state.

Returns FoldError::Serialization if state cannot be serialized to JSON.

pub fn with_hash( id: impl Into<String>, state: S, uuid: Uuid, hash: Hash32, entries_processed: usize, context: FoldContext, fold_version: usize, ) -> Self

Create a checkpoint with a pre-computed hash (for deserialization / testing).

Callers are responsible for ensuring hash is consistent with state. Prefer Checkpoint::new for production use.

Trait Implementations

impl<S: Clone> Clone for Checkpoint<S>

fn clone(&self) -> Checkpoint<S>

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<S: Debug> Debug for Checkpoint<S>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de, S> Deserialize<'de> for Checkpoint<S>

where S: Deserialize<'de>,

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<S> Serialize for Checkpoint<S>

where S: Serialize,

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.