Struct LogFileJournal

pub struct LogFileJournal { /* private fields */ }

The LogFile snapshot capturer will write its snapshots to a linear journal and read them when restoring. It uses the bincode serializer which means that forwards and backwards compatibility must be dealt with carefully.

When opening an existing journal file that was previously saved then new entries will be added to the end regardless of if its been read.

The logfile snapshot capturer uses a 64bit number as a entry encoding delimiter.

Implementations

impl LogFileJournal

pub fn new(path: impl AsRef<Path>) -> Result<LogFileJournal, Error>

pub fn new_readonly(path: impl AsRef<Path>) -> Result<LogFileJournal, Error>

pub fn owned_buffer(&self) -> OwnedBuffer

pub fn backing_store(&self) -> OffloadBackingStore

pub fn from_file(file: File) -> Result<LogFileJournal, Error>

Create a new journal from a file

pub fn from_buffer( buffer: OwnedBuffer, ) -> RecombinedJournal<UnsupportedJournal, LogFileJournalRx>

Create a new journal from a buffer

Trait Implementations

impl Debug for LogFileJournal

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

Formats the value using the given formatter.

impl Journal for LogFileJournal

fn split( self, ) -> (Box<dyn WritableJournal + Sync + Send>, Box<dyn ReadableJournal + Sync + Send>)

Splits the journal into a read and write side

impl ReadableJournal for LogFileJournal

fn read(&self) -> Result<Option<LogReadResult<'_>>, Error>

Returns a stream of snapshot objects that the runtime will use to restore the state of a WASM process to a previous moment in time

fn as_restarted(&self) -> Result<Box<dyn ReadableJournal + Sync + Send>, Error>

Resets the journal so that reads will start from the beginning again

impl WritableJournal for LogFileJournal

fn write<'a>(&'a self, entry: JournalEntry<'a>) -> Result<LogWriteResult, Error>

Takes in a stream of snapshot log entries and saves them so that they may be restored at a later moment

fn flush(&self) -> Result<(), Error>

Flushes the data to disk or network

fn commit(&self) -> Result<usize, Error>

Commits the transaction Returns the number of events committed

fn rollback(&self) -> Result<usize, Error>

Rolls back the transaction and aborts its changes Returns the number of events rolled back