Struct EventStoreReader 

pub struct EventStoreReader<B> { /* private fields */ }

Read-only handle over an EventStore backend.

The reader is the canonical entry point for read-only replay, audit, and verifier scans: it never mutates the backend (no append_batch surface) and it tolerates running and sealed backends uniformly.

Implementations

impl<B: EventStore> EventStoreReader<B>

pub const fn new(backend: B) -> Self

Wraps backend for read-only access.

pub fn manifest(&self) -> Result<RunManifest, EventStoreError>

Returns the manifest of the open run.

Errors

Returns EventStoreError::Backend when no run is open.

pub fn high_watermark(&self) -> Result<u64, EventStoreError>

Returns the largest seq durably acknowledged for the open run.

Errors

Returns EventStoreError::Backend when no run is open.

pub fn scan_seq( &self, seq: u64, ) -> Result<Option<EventStoreEntry>, EventStoreError>

Reads a single entry by seq.

Returns None when seq == 0 or seq exceeds the current high-watermark.

Errors

Returns EventStoreError::HashMismatch when the recomputed entry hash diverges from the stored value, EventStoreError::Gap when the row is missing inside the high-watermark, and EventStoreError::Backend for unclassified backend failures.

pub fn lookup( &self, kind: IndexKind, key: &str, ) -> Result<Option<u64>, EventStoreError>

Looks up the first seq recorded under the given index key.

Errors

Returns EventStoreError::Backend for unclassified backend failures.

pub fn latest_snapshot_anchor( &self, ) -> Result<Option<SnapshotAnchor>, EventStoreError>

Returns the latest snapshot anchor for the run.

Returns Ok(None) when no snapshot anchor has been recorded yet.

Errors

Returns EventStoreError::Backend when no run is open or the backend does not support snapshot anchors, and EventStoreError::Corrupted when a stored anchor cannot decode.

pub fn snapshot_replay_plan( &self, ) -> Result<SnapshotReplayPlan, EventStoreError>

Builds the restore replay bounds from the latest snapshot anchor.

Restore callers fetch and validate the cache-owned snapshot blob first, then replay entries in [from_seq, to_seq]. When an anchor exists, from_seq is anchor.high_watermark + 1; without an anchor, restore replays from seq 1.

Errors

Returns EventStoreError::Backend when no run is open or the backend does not support snapshot anchors, and EventStoreError::Corrupted when the stored anchor points past the durable high-watermark.

pub fn scan_snapshot_replay_tail( &self, ) -> Result<(SnapshotReplayPlan, RangeScan<'_>), EventStoreError>

Scans the forward replay tail after the latest snapshot anchor.

This pairs Self::snapshot_replay_plan with the actual event iterator used by restore: entries start at anchor.high_watermark + 1 when an anchor exists, or at seq 1 when no cache snapshot has been anchored.

Errors

See Self::snapshot_replay_plan.

pub fn scan_range( &self, from: u64, to: u64, direction: ScanDirection, ) -> RangeScan<'_>

Scans entries by seq over the inclusive range [from, to].

The returned iterator pulls DEFAULT_SCAN_CHUNK_SIZE entries at a time from the backend so a multi-million-entry forensics scan keeps the working set bounded while still amortizing per-transaction overhead. The iterator yields one entry per call; backend errors surface as Some(Err(...)) and terminate the scan.

pub fn scan_range_chunked( &self, from: u64, to: u64, direction: ScanDirection, chunk_size: u64, ) -> RangeScan<'_>

Variant of Self::scan_range with a caller-chosen chunk size.

chunk_size == 0 is normalized to 1; the reader never asks the backend for a degenerate empty window because the chunk window is the only progress signal the iterator advances on.

pub fn into_inner(self) -> B

Returns the underlying backend, consuming the reader.

pub const fn backend(&self) -> &B

Returns a reference to the underlying backend.

Trait Implementations

impl<B: Debug> Debug for EventStoreReader<B>

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

Formats the value using the given formatter.