Struct Writer 

pub struct Writer<W: Write> { /* private fields */ }

Implementations

impl<W: Write> Writer<W>

pub fn append<T: Encode>(&mut self, record: T) -> Result<(), T>

Append the record (aka transaction) T to the segment.

If the number of currently buffered records would exceed max_records_in_commit after the method returns, the argument is returned in an Err and not appended to this writer’s buffer.

Otherwise, the record is encoded and and stored in the buffer.

An Err result indicates that Self::commit should be called in order to flush the buffered records to persistent storage.

pub fn commit(&mut self) -> Result<Option<Committed>>

Write the current Commit to the underlying io::Write.

Will do nothing if the current commit is empty (i.e. Commit::n is zero). In this case, None is returned.

Otherwise Some Committed is returned, providing some metadata about the commit.

pub fn epoch(&self) -> u64

Get the current epoch.

pub fn set_epoch(&mut self, epoch: u64)

Update the epoch.

The caller must ensure that:

• The new epoch is greater than the current epoch.
• Self::commit has been called as appropriate.

pub fn min_tx_offset(&self) -> u64

The smallest transaction offset in this segment.

pub fn next_tx_offset(&self) -> u64

The next transaction offset to be written if Self::commit was called.

pub fn is_empty(&self) -> bool

true if the segment contains no commits.

The segment will, however, contain a header. This thus violates the convention that is_empty == (len == 0).

pub fn len(&self) -> u64

Number of bytes written to this segment, including the header.

Trait Implementations

impl<W: Debug + Write> Debug for Writer<W>

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

Formats the value using the given formatter.

impl<W: Write + FileLike> FileLike for Writer<W>

fn fsync(&mut self) -> Result<()>

fn ftruncate(&mut self, tx_offset: u64, size: u64) -> Result<()>