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Guozhang Wang commented on KAFKA-14202: --------------------------------------- Hey [~vvcephei] are you considering the scope for store key schemas only, or both keys and values? > IQv2: Expose binary store schema to store implementations > --------------------------------------------------------- > > Key: KAFKA-14202 > URL: https://issues.apache.org/jira/browse/KAFKA-14202 > Project: Kafka > Issue Type: Improvement > Components: streams > Reporter: John Roesler > Priority: Minor > > One feature of IQv2 is that store implementations can handle custom queries. > Many custom query handlers will need to process the key or value bytes, for > example deserializing them to implement some filter or aggregations, or even > performing binary operations on them. > For the most part, this should be straightforward for users, since they > provide Streams with the serdes, the store implementation, and the custom > queries. > However, Streams will sometimes pack extra data around the data produced by > the user-provided serdes. For example, the Timestamped store wrappers add a > timestamp on the beginning of the value byte array. And in Windowed stores, > we add window timestamps to the key bytes. > It would be nice to have some generic mechanism to communicate those schemas > to the user-provided inner store layers to support users who need to write > custom queries. For example, perhaps we can add an extractor class to the > state store context -- This message was sent by Atlassian Jira (v8.20.10#820010)