Trait CheckpointStore 

pub trait CheckpointStore: Send + Sync {
    // Required methods
    fn is_persistent(&self) -> bool;
    fn stage_checkpoint<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        source_id: &'life1 str,
        sequence: u64,
        source_position: Option<&'life2 Bytes>,
    ) -> Pin<Box<dyn Future<Output = Result<(), IndexError>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait;
    fn read_checkpoint<'life0, 'life1, 'async_trait>(
        &'life0 self,
        source_id: &'life1 str,
    ) -> Pin<Box<dyn Future<Output = Result<Option<SourceCheckpoint>, IndexError>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait;
    fn read_all_checkpoints<'life0, 'async_trait>(
        &'life0 self,
    ) -> Pin<Box<dyn Future<Output = Result<HashMap<String, SourceCheckpoint>, IndexError>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;
    fn clear_checkpoints<'life0, 'async_trait>(
        &'life0 self,
    ) -> Pin<Box<dyn Future<Output = Result<(), IndexError>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;
    fn write_config_hash<'life0, 'async_trait>(
        &'life0 self,
        hash: u64,
    ) -> Pin<Box<dyn Future<Output = Result<(), IndexError>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;
    fn read_config_hash<'life0, 'async_trait>(
        &'life0 self,
    ) -> Pin<Box<dyn Future<Output = Result<Option<u64>, IndexError>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;
}

Atomic checkpoint persistence for source sequence tracking and config hashing.

Method semantics

• stage_checkpoint SHOULD be called between SessionControl::begin and SessionControl::commit for persistent backends. The write is staged into the active session transaction and persisted by the outer commit. For volatile (in-memory) backends, it applies immediately.
• All other methods operate independently of the session transaction and commit on their own.

Source positions

Each source feeding a query has its own checkpoint entry. The opaque source_position bytes allow native stream resumption — on restart, the query reads each source’s position and passes it via resume_from.

Required Methods

fn is_persistent(&self) -> bool

Whether this store persists checkpoints across process restarts.

The orchestration layer uses this to decide whether to propagate resume_from and last_sequence to sources on restart. Volatile (in-memory) stores return false; persistent stores (RocksDB, Garnet) return true.

fn stage_checkpoint<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, source_id: &'life1 str, sequence: u64, source_position: Option<&'life2 Bytes>, ) -> Pin<Box<dyn Future<Output = Result<(), IndexError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Stage a source checkpoint into the active session transaction.

For persistent backends, must be called inside an open session (between SessionControl::begin and SessionControl::commit). Returns an error if no session is active.

For volatile backends (in-memory), applies immediately.

fn read_checkpoint<'life0, 'life1, 'async_trait>( &'life0 self, source_id: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<Option<SourceCheckpoint>, IndexError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Read the committed checkpoint for a single source.

Returns None if no checkpoint has been written for source_id. Reads committed state directly; does not require an active session.

fn read_all_checkpoints<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Result<HashMap<String, SourceCheckpoint>, IndexError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Read all committed source checkpoints, keyed by source id.

Returns an empty map if no checkpoints have been written. Reads committed state directly; does not require an active session.

fn clear_checkpoints<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Result<(), IndexError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Delete all source checkpoints and the config hash.

Used during auto-reset recovery and delete_query(cleanup: true). Standalone commit; not part of any outer session transaction.

fn write_config_hash<'life0, 'async_trait>( &'life0 self, hash: u64, ) -> Pin<Box<dyn Future<Output = Result<(), IndexError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Write the query config hash.

Used at startup to detect query configuration changes that require a full re-bootstrap. Standalone commit.

fn read_config_hash<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Result<Option<u64>, IndexError>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Read the stored config hash.

Returns None if no hash has been written. Called at startup before any session transaction begins.

Implementors

impl CheckpointStore for InMemoryCheckpointStore