Trait TranscriptSink

Source

pub trait TranscriptSink: Send {
    // Required methods
    fn begin(&mut self, header: &TranscriptHeader) -> Result<()>;
    fn record(
        &mut self,
        at: DateTime<Utc>,
        level: Level,
        fact: &StepFact,
    ) -> Result<()>;
    fn finalize(&mut self) -> Result<TranscriptFingerprint>;
}

Expand description

Synchronous, durable observer of StepFacts.

Implementations must record each fact, including syncing it to the underlying storage where applicable, before returning. The executor relies on this to maintain the invariant that the UI never sees a fact that has not been durably persisted.

Required Methods§

Source

fn begin(&mut self, header: &TranscriptHeader) -> Result<()>

Write the header line. Must be called once, before any fact.

§Errors

Returns an error if the header was already written, or the underlying I/O error if the sink cannot persist it.

Source

fn record( &mut self, at: DateTime<Utc>, level: Level, fact: &StepFact, ) -> Result<()>

Record a single fact at level, stamped with the caller-supplied event time at. Must persist before returning, the file-backed implementation calls sync_data so a power loss after record returns cannot drop the fact.

at and level are supplied by the executor, not chosen here, so the sink stays a serializer with no policy of its own.

§Errors

Returns an error if the header has not been written or the transcript is finalized, if the header does not declare level, if the fact holds a value the canonical form does not cover, or the underlying I/O error if the sink cannot persist the fact.

Source