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https://issues.apache.org/jira/browse/KAFKA-9259?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17006183#comment-17006183
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John Roesler commented on KAFKA-9259:
-------------------------------------
There are serdes for the Windowed types, but they need an instance of the inner
serde to wrap.
A good way to approach this is to learn how the windowed serdes get set up.
Maybe just try reading through the code starting from the windowBy operator
through the windowed aggregation to see how the right windowed serde gets
selected and wraps the inner serde.
> suppress() for windowed-Serdes does not work with default serdes
> ----------------------------------------------------------------
>
> Key: KAFKA-9259
> URL: https://issues.apache.org/jira/browse/KAFKA-9259
> Project: Kafka
> Issue Type: Bug
> Components: streams
> Affects Versions: 2.1.0
> Reporter: Matthias J. Sax
> Assignee: Omkar Mestry
> Priority: Major
> Labels: newbie
>
> The suppress() operator either inherits serdes from its upstream operator or
> falls back to default serdes from the config.
> If the upstream operator is an windowed aggregation, the window-aggregation
> operator wraps the user passed-in serde with a window-serde and pushed it
> into suppress() – however, if default serdes are used, the window-aggregation
> operator cannot push anything into suppress(). At runtime, it just creates a
> default serde and wraps it according. For this case, suppress() also falls
> back to default serdes; however, it does not wrap the serde and thus a
> ClassCastException is thrown when the serde is used later.
> suppress() is already aware if the upstream aggregation is time/session
> windowed or not and thus should use this information to wrap default serdes
> accordingly.
> The current workaround for windowed-suppress is to overwrite the default
> serde upstream to suppress(), such that suppress() inherits serdes and does
> not fall back to default serdes.
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