Sink.completionStageSink

Streams the elements to the given future sink once it successfully completes.

Sink operators

Description

Streams the elements through the given future flow once it successfully completes. If the future fails the stream is failed.

completionStageSink uses the same lazy materialization semantics as lazyCompletionStageSink: the nested sink is not materialized until the first upstream element arrives. If the stream completes before the first element, the materialized value fails with org.apache.pekko.stream.NeverMaterializedException.

If you want this to work for empty streams as well, use eagerCompletionStageSink.

Reactive Streams semantics