Struct InMemoryCheckpointStore 

pub struct InMemoryCheckpointStore { /* private fields */ }

A bounded in-memory checkpoint store.

Each stream maintains its own sorted list of checkpoints. When the number of checkpoints for a stream exceeds max_per_stream, the oldest ones are evicted automatically.

Implementations

impl InMemoryCheckpointStore

pub fn new(max_per_stream: usize) -> Self

Create a store that retains at most max_per_stream checkpoints per stream.

pub fn save(&mut self, state: CheckpointState) -> Result<(), StreamingError>

Save a checkpoint state. The list is kept sorted by sequence number.

pub fn latest(&self, stream_id: &str) -> Option<&CheckpointState>

Return the most recent checkpoint for the given stream, or None.

pub fn list(&self, stream_id: &str) -> Vec<&CheckpointState>

Return all checkpoints for the given stream, sorted ascending by sequence.

pub fn delete_before(&mut self, stream_id: &str, sequence: u64)

Remove all checkpoints for stream_id with sequence number less than sequence.

pub fn checkpoint_count(&self, stream_id: &str) -> usize

Number of checkpoints currently stored for the given stream.