[ 
https://issues.apache.org/jira/browse/KAFKA-3545?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15583196#comment-15583196
 ] 

Andrew Musselman commented on KAFKA-3545:
-----------------------------------------

Not sure who to notifiy for closing tickets; [~gwenshap] could you suggest 
someone?

> Generalized Serdes for List/Map
> -------------------------------
>
>                 Key: KAFKA-3545
>                 URL: https://issues.apache.org/jira/browse/KAFKA-3545
>             Project: Kafka
>          Issue Type: Improvement
>          Components: streams
>            Reporter: Greg Fodor
>            Priority: Minor
>              Labels: api, newbie
>             Fix For: 0.10.1.0
>
>
> In working with Kafka Streams I've found it's often the case I want to 
> perform a "group by" operation, where I repartition a stream based on a 
> foreign key and then do an aggregation of all the values into a single 
> collection, so the stream becomes one where each entry has a value that is a 
> serialized list of values that belonged to the key. (This seems unrelated to 
> the 'group by' operation talked about in KAFKA-3544.) Basically the same 
> typical group by operation found in systems like Cascading.
> In order to create these intermediate list values I needed to define custom 
> avro schemas that simply wrap the elements of interest into a list. It seems 
> desirable that there be some basic facility for constructing simple Serdes of 
> Lists/Maps/Sets of other types, potentially using avro's serialization under 
> the hood. If this existed in the core library it would also enable the 
> addition of higher level operations on streams that can use these Serdes to 
> perform simple operations like the "group by" example I mention.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to