batchWeighted
Allow for a slower downstream by passing incoming elements and a summary into an aggregate function as long as there is backpressure and a maximum weight batched elements is not yet reached.
Signature
Source.batchWeightedSource.batchWeighted Flow.batchWeightedFlow.batchWeighted
Description
Allow for a slower downstream by passing incoming elements and a summary into an aggregate function as long as there is backpressure and a maximum weight batched elements is not yet reached. The weight of each element is determined by applying costFn. When the maximum total weight is reached and downstream still backpressures batch will also backpressure.
Will eagerly pull elements, this behavior may result in a single pending (i.e. buffered) element which cannot be aggregated to the batched value.
Reactive Streams semantics
emits downstream stops backpressuring and there is a batched element available
backpressures batched elements reached the max weight limit of allowed batched elements & downstream backpressures
completes upstream completes and a “possibly pending” element was drained