[ https://issues.apache.org/jira/browse/KAFKA-3729?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Matthias J. Sax reopened KAFKA-3729: ------------------------------------ > Auto-configure non-default SerDes passed alongside the topology builder > ------------------------------------------------------------------------ > > Key: KAFKA-3729 > URL: https://issues.apache.org/jira/browse/KAFKA-3729 > Project: Kafka > Issue Type: Improvement > Components: streams > Reporter: Fred Patton > Assignee: Ted Yu > Priority: Major > Labels: api, newbie > Fix For: 2.3.0 > > Attachments: 3729.txt, 3729.v6.txt > > > From Guozhang Wang: > "Only default serdes provided through configs are auto-configured today. But > we could auto-configure other serdes passed alongside the topology builder as > well." > After the PR was merged, we realized that the current approach to implement > this features is actually not backward compatible. Thus, we need to revert > the commit for now to not break backward compatibility in 2.3 release. After > some more thinking, it seems that this feature is actually more complicated > to get right as it seem on the surface and hence it would required a proper > KIP. > The following issues are identified: > * in the new code, configure() would be called twice, one in user code (if > people don't rewrite existing applications) and later via Kafka Streams – the > second call could "reconfigure" the Serde and overwrite the correct > configuration from the first call done by the user > * if there are multiple Serdes using the same configuration parameters > names, it's only possible to specify this parameter name once in the global > StreamsConfig; hence, it's not possible for users to configure both Serdes > differently > * basically, the global StreamsConfig needs to contain all configuration > parameters over all used Serdes to make a potential second call to > `configure()` idempotant > To address the issues, some ideas would be: > * pass in the configuration via the constructor and deprecate `configure()` > method > * add a new method `isConfigured()` that would allow to skip the second > configuration call within Kafka Streams runtime > There might be other ways to address this, and the different options should > be discussed on the KIP. -- This message was sent by Atlassian JIRA (v7.6.3#76005)