MINOR:Upgrade guide updates for
Reviewers: A. Sophie Blee-Goldmann John Roesler Matthias J. Sax
<!-- Placeholder KIP-213 -->
<p>
In the 2.4 release, you now can name all operators in a Kafka Streams DSL topology via
- <a href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-307%3A+Allow+to+define+custom+processor+names+with+KStreams+DSL">KIP-307</p>.
+ <a href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-307%3A+Allow+to+define+custom+processor+names+with+KStreams+DSL">KIP-307</a>.
Giving your operators meaningful names makes it easier to understand the topology
description (<code>Topology#describe()#toString()</code>) and
understand the full context of what your Kafka Streams application is doing.
either <code>Joined</code> or the new <code>StreamJoined</code> object.
</p>
- <!-- Placeholder KIP-479 -->
+ <p>
+ Before the 2.4.0 version of Kafa Streams, users of the DSL could not name the state stores involved in a stream-stream join.
+ If users changed their topology and added a operator before the
+ join, the internal names of the state stores would shift, requiring an application reset when redeploying.
+ In the 2.4.0 release, Kafka Streams adds the <code>StreamJoined</code>
+ class, which gives users the ability to name the join processor, repartition topic(s) (if a repartition is required),
+ and the state stores involved in the join. Also, by naming the state stores, the changelog topics
+ backing the state stores are named as well. It's important to note that naming the stores
+ <strong>will not</strong> make them queryable via Interactive Queries.
+ <br/>
+ Another feature delivered by <code>StreamJoined</code> is that you can now configure the type of state store used in the join.
+ You can elect to use in-memory stores or custom state stores for a stream-stream join. Note that the provided stores
+ will not be available for querying via Interactive Queries. With the addition
+ of <code>StreamJoined</code>, stream-stream join operations
+ using <code>Joined</code> have been deprecated. Please switch over to stream-stream join methods using the
+ new overloaded methods. You can get more details from
+ <a href="https://cwiki.apache.org/confluence/display/KAFKA/KIP-479%3A+Add+StreamJoined+config+object+to+Join">KIP-479</a>.
+ </p>
<p>
With the introduction of incremental cooperative rebalancing, Streams no longer requires all tasks be revoked at the beginning of a rebalance. Instead, at the completion of the rebalance only those tasks which are to be migrated to another consumer
