Struct MetricsLogReader

pub struct MetricsLogReader<R: Read> {
    pub header: LogHeader,
    /* private fields */
}

A streaming reader for metric logs. If the underlying reader supports seeks, it is possible to get SeekTokens which may be used to seek to previous frames in the stream.

Fields

header: LogHeader

Implementations

impl<R: Read> MetricsLogReader<R>

pub fn new(reader: R) -> Result<Self>

Constructs a bare metrics log reader.

pub fn read_frame( &mut self, ) -> Result<Option<(UnixTimestampMilliseconds, Frame)>>

Reads a frame. Returns the start time of the frame and the frame itself.

impl<R: Read + Seek> MetricsLogReader<R>

pub fn read_frame_rewindable( &mut self, ) -> Result<Option<(SeekToken, UnixTimestampMilliseconds, Frame)>>

Reads a new frame, and returns a seek token that can be used to rewind such that you can ‘undo’ the read.

pub fn seek(&mut self, seek_token: SeekToken) -> Result<SeekToken>

Seeks to a position in the stream. The given seek token MUST have come from this instance’s read_from_rewindable function. Otherwise, corrupt frames may be read. The old position is returned as a seek token.