Struct DurableCheckpointMetadata 

#[non_exhaustive]
pub struct DurableCheckpointMetadata {
    pub identity: DurableCheckpointIdentity,
    pub block: DurableCheckpointBlock,
    pub delivery_token: Option<Vec<u8>>,
    pub delivery_witness: Option<B256>,
    pub subscriber_checkpoint: Option<Vec<u8>>,
    pub runtime_checkpoint: Option<Vec<u8>>,
}

Public commit metadata stored alongside the cache snapshot.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

identity: DurableCheckpointIdentity

Durable consumer identity guarded on restore.

block: DurableCheckpointBlock

Last canonical block whose event effects are included.

delivery_token: Option<Vec<u8>>

Last subscriber delivery token included in the snapshot.

If the subscriber replays this token after an acknowledgement was lost, the consumer can acknowledge it without applying the batch again.

delivery_witness: Option<B256>

Core-computed witness for the exact delivery associated with delivery_token.

The witness is intentionally retained with its token when a later tokenless barrier advances the overall checkpoint. On replay, the engine requires the incoming delivery to reproduce this witness before it can acknowledge the token without reapplying the batch. A token supplied by low-level callers without a witness cannot use that replay shortcut.

subscriber_checkpoint: Option<Vec<u8>>

Opaque provider-specific resume state committed with this snapshot.

The cache never interprets this value. A subscriber extension may use it to resume from a native cursor after process restart.

runtime_checkpoint: Option<Vec<u8>>

Opaque core-runtime recovery state committed with the cache snapshot.

The cache layer stores these bytes but does not interpret them. The reactive engine uses them to restore finality and its bounded rollback journal after restart.

Implementations

impl DurableCheckpointMetadata

pub fn new( identity: DurableCheckpointIdentity, block: DurableCheckpointBlock, ) -> Self

Construct checkpoint metadata.

pub fn with_delivery_token(self, delivery_token: impl Into<Vec<u8>>) -> Self

Attach the subscriber token whose effects are represented by this state.

pub fn with_delivery_witness(self, delivery_witness: B256) -> Self

Attach the core delivery witness associated with the delivery token.

Most applications should let the reactive engine compute this value. This builder exists for checkpoint migration and other low-level integrations that reproduce the core witness contract exactly.

pub fn with_subscriber_checkpoint(self, checkpoint: impl Into<Vec<u8>>) -> Self

Attach opaque provider-specific resume state represented by this state.

pub fn with_runtime_checkpoint(self, checkpoint: impl Into<Vec<u8>>) -> Self

Attach opaque core-runtime recovery state represented by this snapshot.

Trait Implementations

impl Clone for DurableCheckpointMetadata

fn clone(&self) -> DurableCheckpointMetadata

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for DurableCheckpointMetadata

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for DurableCheckpointMetadata

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for DurableCheckpointMetadata

impl PartialEq for DurableCheckpointMetadata

fn eq(&self, other: &DurableCheckpointMetadata) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for DurableCheckpointMetadata

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for DurableCheckpointMetadata