Struct EnvelopeWriter 

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

Appends envelopes to any Write: a file, a buffer, a compressor.

Wrap a file in std::io::BufWriter yourself when you write many envelopes: the writer does not buffer. flush after the last write, or finish, so the tail is not left in a buffer when the program ends.

Examples

See the module record.

Implementations

impl<W: Write> EnvelopeWriter<W>

pub fn new(out: W) -> Result<Self, LogError>

Starts a new log in out: writes the header line.

Errors

LogError::Io when the header cannot be written.

pub fn write(&mut self, envelope: &Envelope) -> Result<(), LogError>

Appends one envelope as one line.

Errors

LogError::Io when the write fails. The line may be half written then: do not append to the same file after an error, start a new one.

pub fn written(&self) -> u64

How many envelopes were written (the header is not counted).

pub fn flush(&mut self) -> Result<(), LogError>

Flushes the underlying writer.

Errors

LogError::Io when the flush fails.

pub fn finish(self) -> Result<W, LogError>

Flushes and gives the underlying writer back.

Errors

LogError::Io when the flush fails.