Struct wral::Wal

pub struct Wal<S = NoState> { /* fields omitted */ }

Write ahead logging.

Implementations

impl<S> Wal<S>

pub fn create(config: Config, state: S) -> Result<Wal<S>> where
    S: State, 

Create a new Write-Ahead-Log instance, while create a new journal, older journals matching the name shall be purged.

pub fn load(config: Config) -> Result<Wal<S>> where
    S: Default + State, 

Load an existing journal under dir, matching name. Files that don’t match the journal file-name structure or journals with corrupted batch or corrupted state shall be ignored.

Application state shall be loaded from the last batch of the last journal.

pub fn close(self, purge: bool) -> Result<Option<u64>>

Close the Wal instance. To purge the instance pass purge as true.

impl<S> Wal<S>

pub fn add_op(&self, op: &[u8]) -> Result<u64>

Add a operation to WAL, operations are pre-serialized and opaque to Wal instances. Return the sequence-number for this operation.

impl<S> Wal<S>

pub fn iter(&self) -> Result<impl Iterator<Item = Result<Entry>>>

Iterate over all entries in this Wal instance, entries can span across multiple journal files. Iteration will start from lowest sequence-number to highest.

pub fn range<R>(&self, range: R) -> Result<impl Iterator<Item = Result<Entry>>> where
    R: RangeBounds<u64>, 

Iterate over entries whose sequence number fall within the specified range.

Trait Implementations

impl<S> Clone for Wal<S>

fn clone(&self) -> Wal<S>

Returns a copy of the value.

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

Performs copy-assignment from source.