Status
Current state: Accepted
Discussion thread: here
Voting thread: here
JIRA:
Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).
Motivation
KIP-479, implemented in Kafka 2.4.0, added StreamJoined
to Kafka Streams as a way to extend features of Materialized
to stream-stream joins. During the KIP discussion, adding the option to disable logging was discussed but not implemented through KIP-479. Adding this feature allows users more flexibility over their store and fits with the original goal of extending Materialized
features to stream-stream joins.
Public Interfaces
This KIP will add the following two methods as well as a loggingEnabled
variable and a topicConfig
variable to store any configs passed in when enabling logging.
public StreamJoined<K, V1, V2> withLoggingEnabled(final Map<String, String> config) {} public StreamJoined<K, V1, V2> withLoggingDisabled() {}
Proposed Changes
We will add two new methods to StreamJoined
to allow users to determine whether they want logging for their stores. This config sets the logging decision for both stores, meaning that if logging is disabled for thisWindowStore
, it will also be disabled for otherWindowStore
. The default value for loggingEnabled
will be true
, enabling logging for both stores if the user does not set the values manually.
Compatibility, Deprecation, and Migration Plan
As this is not deprecating or changing default behavior there should be no compatibility issues
Rejected Alternatives
- Including
withRetentionPeriod()
→ skipped as there is no reason for a user to configure a certain retention time for joins - Including withCachingEnabled/Disabled → skipped because joins always retain duplicates which is incompatible with caching (see )