Struct SourceProvidedGenerator 

pub struct SourceProvidedGenerator { /* private fields */ }

Watermark generator for sources with embedded watermarks.

Some sources (like Kafka with EOS) may provide watermarks directly. This generator tracks both event timestamps and explicit watermarks.

Implementations

impl SourceProvidedGenerator

pub fn new(fallback_lateness: i64, prefer_source: bool) -> Self

Creates a new source-provided generator.

Arguments

• fallback_lateness - Lateness for fallback bounded generator
• prefer_source - If true, source watermarks take precedence

pub fn on_source_watermark(&mut self, watermark: i64) -> Option<Watermark>

Updates the watermark from the source.

Call this when the source provides an explicit watermark.

Trait Implementations

impl WatermarkGenerator for SourceProvidedGenerator

fn on_event(&mut self, timestamp: i64) -> Option<Watermark>

Process an event timestamp and potentially emit a new watermark.

fn on_periodic(&mut self) -> Option<Watermark>

Called periodically to emit watermarks based on wall-clock time.

fn current_watermark(&self) -> i64

Returns the current watermark value without advancing it.

fn advance_watermark(&mut self, timestamp: i64) -> Option<Watermark>

Advances the watermark to at least the given timestamp from an external source.

fn is_processing_time(&self) -> bool

Whether the watermark is processing-time based (wall clock), rather than derived from the event-time column. Such a watermark lives in a different time domain than the event timestamps, so comparing the two to drop “late” rows would discard every event — callers skip source-side late-filtering when this is true. Defaults to false (event-time generators).