Struct InMemoryBackend 

pub struct InMemoryBackend { /* private fields */ }

A simple, non-durable in-memory implementation of the Backend trait. Intended for testing, examples, and rapid prototyping.

Implementations

impl InMemoryBackend

pub fn new() -> Self

Creates a new, empty in-memory backend.

Trait Implementations

impl Backend for InMemoryBackend

fn get_committed_versions( &self, key: &[u8], ) -> Result<Vec<CommittedVersion>, String>

Returns all committed versions for a key, ordered ascending by commit_ts.

fn get_latest_committed( &self, key: &[u8], ) -> Result<Option<CommittedVersion>, String>

Returns the most recent committed version for a key, if any.

fn get_visible_committed( &self, key: &[u8], read_ts: Timestamp, ) -> Result<Option<CommittedVersion>, String>

Returns the most recent committed version for a key that is visible at or before read_ts.

fn get_latest_commit_ts(&self, key: &[u8]) -> Result<Option<Timestamp>, String>

Returns the timestamp of the most recent committed version for a key, if any.

fn get_intent(&self, key: &[u8]) -> Result<Option<Intent>, String>

Fetches the active intent for a given key, if any exists.

fn put_intent(&mut self, intent: Intent) -> Result<(), String>

Writes a single intent to the backend.

fn remove_intent( &mut self, key: &[u8], txn_id: TxnId, start_ts: Timestamp, ) -> Result<bool, String>

Removes an intent from the backend if it matches the given txn_id and start_ts. Returns true if removed, false otherwise.

fn put_committed(&mut self, version: CommittedVersion) -> Result<(), String>

Writes a single committed version to the backend.

fn put_committed_batch( &mut self, versions: Vec<CommittedVersion>, ) -> Result<(), String>

Writes multiple committed versions atomically. Must be all-or-nothing.

fn remove_committed_version( &mut self, key: &[u8], commit_ts: Timestamp, ) -> Result<(), String>

Removes a specific committed version during garbage collection.

fn all_keys(&self) -> Result<Vec<Key>, String>

Returns a deduplicated, sorted list of all keys currently managed by the backend.

fn put_intents_batch(&mut self, intents: Vec<Intent>) -> Result<(), String>

Writes multiple intents atomically. Must be all-or-nothing.

fn commit_intents_batch( &mut self, commits: Vec<CommittedVersion>, removed_intents: Vec<(Key, TxnId, Timestamp)>, ) -> Result<(), String>

Converts multiple intents into committed versions atomically. Must create the versions and remove the intents in a single durable transaction.

fn remove_intents_batch( &mut self, intents: Vec<(Key, TxnId, Timestamp)>, ) -> Result<(), String>

Removes multiple intents atomically. Must be all-or-nothing.

fn keys_from( &self, start: Option<&[u8]>, limit: usize, ) -> Result<Vec<Key>, String>

Returns up to limit keys strictly ordered, starting from start (inclusive if provided).

fn keys_from_prefix( &self, prefix: &[u8], start: Option<&[u8]>, limit: usize, ) -> Result<Vec<Key>, String>

Returns up to limit keys starting with prefix, strictly ordered, starting from start if provided. Excludes intents and returns committed keys only.

fn get_committed_timestamps_before( &self, key: &[u8], before_ts: Timestamp, limit: usize, ) -> Result<Vec<Timestamp>, String>

Returns the limit newest commit timestamps strictly before before_ts for the given key. Ordered descending (newest first).

fn collapse_tombstone( &mut self, key: &[u8], tombstone_ts: Timestamp, older_ts: Vec<Timestamp>, ) -> Result<(), String>

Atomically removes a tombstone version and every supplied older version. Callers must pass the complete older version set for a final tombstone collapse.

impl Clone for InMemoryBackend

fn clone(&self) -> InMemoryBackend

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for InMemoryBackend

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

Formats the value using the given formatter.

impl Default for InMemoryBackend

fn default() -> InMemoryBackend

Returns the “default value” for a type.