.. _streams_upgrade-guide:

Upgrade Guide
=============

Upgrading from CP 3.0.0 (Kafka 0.10.0.0-cp1) to CP 3.0.1 (Kafka 0.10.0.1-cp1)
-----------------------------------------------------------------------------

.. _streams_upgrade-guide_3.0.1-compatibility:

Compatibility
^^^^^^^^^^^^^

Confluent Kafka Streams 0.10.0.1-cp1 is a bug fix release and has no breaking changes.

* **Backward-compatible to CP 3.0.0 clusters (Kafka 0.10.0.0-cp1):**
  Kafka Streams applications built with CP 3.0.1 (Kafka 0.10.0.1-cp1) will work with existing Kafka clusters running
  CP 3.0.0 (Kafka 0.10.0.0-cp1).

* **Forward-compatible to CP 3.0.1 clusters (Kafka 0.10.0.1-cp1):**
  Existing Kafka Streams applications built with CP 3.0.0 (Kafka 0.10.0.0-cp1) will work with upgraded Kafka clusters
  running CP 3.0.1 (Kafka 0.10.0.1-cp1).


.. _streams_upgrade-guide_3.0.1-upgrade-apps:

Upgrading your Kafka Streams applications to CP 3.0.1
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

To make use of CP 3.0.1 (Kafka 0.10.0.1-cp1), you just need to update the Kafka Streams dependency of your application
to use the version number ``0.10.0.1-cp1``, and then recompile your application.

For example, in your ``pom.xml`` file:

.. sourcecode:: xml

    <dependency>
        <groupId>org.apache.kafka</groupId>
        <artifactId>kafka-streams</artifactId>
        <!-- update version from 0.10.0.0-cp1 to 0.10.0.1-cp1 -->
        <version>0.10.0.1-cp1</version>
    </dependency>


Full upgrade workflow
^^^^^^^^^^^^^^^^^^^^^

A typical workflow for upgrading Kafka Streams applications from CP 3.0.0 to CP 3.0.1 has the following steps:

#. **Upgrade your application:**  See :ref:`upgrade instructions <streams_upgrade-guide_3.0.1-upgrade-apps>` above.
#. **Stop the old application:** Stop the old version of your application, i.e. stop all the application instances
   that are still running the old version of the application.
#. **Start the upgraded application:** Start the upgraded version of your application, with as many instances as
   needed.  By default, the upgraded application will resume processing its input data from the point where the old
   version was stopped (see previous step).