Struct FoldSnapshot 

pub struct FoldSnapshot {
    pub conversation: ConversationId,
    pub as_of: BTreeMap<u32, u64>,
    pub state: Vec<u8>,
}

A fold snapshot: the folded state plus the per-partition offsets it folded through. as_of maps a partition id to the last offset folded into state (inclusive), matching the cursor’s per-partition offsets, so a multi-partition fold resumes correctly. Resume seeds the cursor at offset + 1 per partition, because the cursor takes the next offset to read (exclusive) while the snapshot records the last offset folded (inclusive).

Fields

conversation: ConversationId

The fold this snapshots (the conversation or journal partition key).

as_of: BTreeMap<u32, u64>

Per-partition last folded offset, inclusive. A windowless fold over one partition is a single entry.

state: Vec<u8>

The opaque folded state. The codec is the producer’s choice, the wire crate never inspects it.

Implementations

impl FoldSnapshot

pub fn resume_offset(&self, partition: u32) -> u64

The offset a partition’s resume should start reading from: one past the last folded offset, or 0 for a partition the snapshot did not cover.

Trait Implementations

impl Clone for FoldSnapshot

fn clone(&self) -> FoldSnapshot

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for FoldSnapshot

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for FoldSnapshot

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for FoldSnapshot

impl PartialEq for FoldSnapshot

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for FoldSnapshot

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 FoldSnapshot