apache_beam.runners.direct.watermark_manager module¶
Manages watermarks of PCollections and AppliedPTransforms.
- class apache_beam.runners.direct.watermark_manager.WatermarkManager(clock, root_transforms, value_to_consumers, transform_keyed_states)[source]¶
Bases:
object
For internal use only; no backwards-compatibility guarantees.
Tracks and updates watermarks for all AppliedPTransforms.
- WATERMARK_POS_INF = Timestamp(9223372036854.775000)¶
- WATERMARK_NEG_INF = Timestamp(-9223372036854.775000)¶
- get_watermarks(applied_ptransform: AppliedPTransform) _TransformWatermarks [source]¶
Gets the input and output watermarks for an AppliedPTransform.
If the applied_ptransform has not processed any elements, return a watermark with minimum value.
- Parameters:
applied_ptransform – AppliedPTransform to get the watermarks for.
- Returns:
A snapshot (TransformWatermarks) of the input watermark and output watermark for the provided transform.