.. _c3_add_topics:

##########
Add topics
##########

Add topics to a cluster. You can add a topic with default settings, or add a 
topic with customized settings.

.. _c3_all_topics:

All Topics page
===============

To access the All Topics page, click the cluster from the navigation bar and click 
**Topics** from the cluster submenu.

Use the All Topics page to:

- View a summary of topics for a cluster.
- Search for topics.
- Show or hide internal topics.
- Add a topic to a cluster.
- Sort the columns in the Topics table.
- Navigate to other features for topics by clicking the linked topic name:

  - :ref:`Overview <c3_topics_overview>`.
  - :ref:`Schema <topicschema>`.
  - Inspect (:ref:`Message browser <c3_topic_message_browser>`).
  - :ref:`Settings <c3_edit_topic>` for topic configuration.
  - Query in KSQL - Registers a stream or table for a topic.
  - Consumer lag - :ref:`View consumer lag <c3_view_topic_consume_metrics>` at the topic level. 
    You can view consumer lag for a consumer group from 
    the :ref:`Consumers <controlcenter_userguide_consumers>` menu.


.. figure:: ../../images/c3-all-topics-page.png
   :width: 600px
   :alt: All Topics page in Control Center

   All Topics page in Control Center

Availability (under-replicated partitions, out of sync followers and observers) 
and Throughput (bytes per second produced and consumed) details are shown for each topic.

.. _c3_topics_overview:

Topics Overview page
--------------------

To access the topics Overview page:

#. Select a cluster from the navigation bar and click the **Topics** menu.

#. In the Topics table, click the topic name link
   :ref:`c3_all_topics`. The Overview page automatically opens after adding a 
   topic.

Use the Overview page to:

- View a topic overview with a health rollup.
- Drill into topic metric metrics by 
  clicking the **Production**, **Consumption**, or **Availability** panels.
- Search for partitions by partition ID.
- View partition, replica placement, offset, and partition size details.

.. figure:: ../../images/c3-topics-overview-page.png
   :width: 600px
   :alt: Topics Overview page in Control Center

   Topics Overview clickable metrics panels

Navigate to another feature for a topic by clicking the 
:ref:`Messages <c3_topic_message_browser>`, :ref:`Schema <topicschema>`, 
or :ref:`Configuration <c3_edit_topic>` tabs.


.. _c3_add_topic_defaults:

Add a topic with default settings
=================================

#. Select a cluster from the navigation bar and click the **Topics** menu. 
   The :ref:`c3_all_topics` appears.

#. Click **Add a Topic**.

   .. figure:: ../../images/c3-topics-new-topic.png
      :width: 600px
      :alt: New topic form in Control Center

      New topic form in Control Center

#. Enter a unique topic name.
  
   .. note:  The name cannot be edited after the topic has been saved.

#. Select or type a custom number of partitions.

#. Click **Create with defaults**. The topic is created and the topic details 
   :ref:`Overview page <c3_topics_overview>` appears for the topic.


.. _c3_add_topic_custom:

Add a topic with custom settings
================================

On the customize settings form, a variety of other settings are 
available. This is not an exhaustive list, 
but the most commonly modified settings are available. After a topic has been 
created, further modification of topic settings can be 
done using the :ref:`Edit Settings <c3_edit_topic>` form.

#. Select a cluster from the navigation bar and click the **Topics** menu. 
   The :ref:`c3_all_topics` appears.

#. Click **Add a Topic**.

#. Enter a unique topic name.
  
   .. note:: The topic name and the number of partitions cannot be edited after 
             the topic has been saved. To learn more about topic configuration 
             overrides, creating and deleting topics on the 
             command line, and changing the replication factor, 
             see 
             `Topic-level configs <https://kafka.apache.org/documentation/#topicconfigs>`__ 
             and 
             `Kafka Operations Post-Deployment <https://docs.confluent.io/current/kafka/post-deployment.html>`__.

#. Select or type a custom number of partitions.

#. Click **Customize Settings**.

   .. figure:: ../../images/c3-topics-new-topic-custom-settings.png
      :width: 600px
      :alt: New topic with Customized Settings in Control Center

      New Topic with Customized Settings

      The **Topic Summary** pane shows a summary of values that will be used to 
      create the topic. If a dashed line `--` is shown for a configuration 
      option, it will inherit the cluster default.

#. Make any additional selections or changes to the custom settings.

#. (Optional) To edit **Expert Settings** when adding a topic, select 
   **Manually configure other topic configuration options**.

   .. figure:: ../../images/c3-topics-expert-settings.png
      :scale: 80%

#. Click **Save & create**. To return to the create with defaults form without 
   customizing settings, click **Back** before saving.