Struct JournalWriter 

pub struct JournalWriter { /* private fields */ }

Append-only journal writer.

The writer stamps each event with monotonically increasing seq, a fresh event_id, mono_ns elapsed since mono_origin, the current wall-clock ts_utc, and the writer’s run_id.

Implementations

impl JournalWriter

pub fn append( &mut self, event: EngineEvent, ) -> Result<EngineEvent, JournalError>

Append an event to the journal.

The writer overwrites the event’s seq, event_id, mono_ns, ts_utc, and run_id fields, then returns the finalized event.

pub fn stamp( &mut self, event: EngineEvent, ) -> Result<(EngineEvent, Vec<u8>), JournalError>

Stamp envelope fields, compute hash chain, and serialize to frame bytes.

Performs no disk I/O and does not mutate internal chain state. Returns (stamped_event, length_prefixed_frame_bytes).

pub fn write_frame(&mut self, frame: &[u8]) -> Result<(), JournalError>

Write pre-serialized frame bytes to the journal file.

Writes the frame and optionally fsyncs according to the configured FsyncPolicy.

pub fn sync(&mut self) -> Result<(), JournalError>

Explicitly fsync the journal file.

pub fn next_seq(&self) -> u64

Return the next sequence number that will be assigned.

pub fn run_id(&self) -> Uuid

Return the run ID.

pub fn path(&self) -> &Path

Return the journal file path.

pub fn fsync_policy(&self) -> FsyncPolicy

Return the configured fsync policy.

pub fn last_record_hash(&self) -> Option<&str>

Return the last record hash (for chain verification after close).

pub fn try_clone_file(&self) -> Result<File, JournalError>

Clone the underlying file descriptor.

Used by super::async_writer::AsyncJournalWriter to hand an independent fd to the background write thread.