Enum SampleCursorItem 

#[non_exhaustive]
pub enum SampleCursorItem {
    Timed {
        track_id: u32,
        sample: Sample,
    },
    Sparse {
        track_id: u32,
        sample: Sample,
    },
    Lagged {
        skipped: u64,
    },
    Degraded {
        skipped: u64,
    },
}

Available on crate feature std only.

One item SampleCursor::poll can hand back: data from either retention class, or a loss report.

#[non_exhaustive]: this is the growth point for anything a cursor might need to surface beyond “sample” or “loss” later, without a breaking change to every match arm in the workspace.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Timed

A RetentionClass::Timed sample for track_id.

Fields

track_id: u32

The publishing track.

sample: Sample

The sample itself. Cloned from the ring’s stored copy — Sample.data: Bytes is shared, not copied; see Zero-copy fan-out.

Sparse

A RetentionClass::Sparse sample for track_id.

Fields

track_id: u32

The publishing track.

sample: Sample

The sample itself; see the Timed variant’s doc for the zero-copy note.

Lagged

This cursor fell behind the Timed ring: skipped entries were evicted before it read them. Ordinary loss — resume from the next sample; see RetentionClass::Timed.

Fields

skipped: u64

Exact count of Timed entries evicted since this cursor’s last successful read of that class.

Degraded

This cursor fell behind the Sparse ring: skipped entries were evicted before it read them. Not ordinary loss — the consumer’s derived state (e.g. splice-point tracking) is now wrong, not merely gapped; see RetentionClass::Sparse for what a consumer is expected to do about it.

Fields

skipped: u64

Exact count of Sparse entries evicted since this cursor’s last successful read of that class.

Trait Implementations

impl Clone for SampleCursorItem

fn clone(&self) -> SampleCursorItem

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SampleCursorItem

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

Formats the value using the given formatter.