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Elias Levy commented on KAFKA-4217: ----------------------------------- That would work as well. > KStream.transform equivalent of flatMap > --------------------------------------- > > Key: KAFKA-4217 > URL: https://issues.apache.org/jira/browse/KAFKA-4217 > Project: Kafka > Issue Type: Improvement > Components: streams > Affects Versions: 0.10.0.1 > Reporter: Elias Levy > Assignee: Guozhang Wang > > {{KStream.transform}} gives you access to state stores while allowing you to > return zero or one transformed {{KeyValue}}. Alas, it is unclear what method > you should use if you want to access state stores and return zero or multiple > {{KeyValue}}. Presumably you can use {{transform}}, always return {{null}}, > and use {{ProcessorContext.forward}} to emit {{KeyValues}}. > It may be good to introduce a {{transform}}-like {{flatMap}} equivalent, or > allow store access from other {{KStream}} methods, such as {{flatMap}} itself. -- This message was sent by Atlassian JIRA (v6.3.4#6332)