Add spec of host monitors by kubernetes

This spec is mainly to add a new host monitoring driver
to masakari-monitors using the Kubernetes-client.

Implementes: blueprint host-monitors-by-kubernetes
Change-Id: Ifbe02f61bf935d16d546ffdd20e7173170d87b4d

specs/2024.1/approved/host-monitors-by-kubernetes.rst

@@ -0,0 +1,138 @@
+..
+ This work is licensed under a Creative Commons Attribution 3.0 Unported
+ License.
+ http://creativecommons.org/licenses/by/3.0/legalcode
+
+==========================================
+host monitors by kubernetes
+==========================================
+
+https://blueprints.launchpad.net/masakari/+spec/host-monitors-by-kubernetes
+
+
+Problem description
+===================
+
+When using Openstack on Kubernetes, the current host monitoring process
+lacks efficiency and simplicity, requiring additional software such as
+Consul or Pacemaker.
+
+Proposed change
+===============
+
+This spec is mainly to add a new host monitoring driver to masakari-monitors
+using the Kubernetes-client. By leveraging the Kubernetes API, kubernetes-native
+openstack operator can efficiently retrieve and monitor the status of the host
+(node) without the complexities associated with external configuration tools like
+Consul or Pacemaker.
+
+Administrator can set the host monitoring driver to Kubernetes in the host
+configuration.
+
+
+Alternatives
+------------
+
+None
+
+Data model impact
+-----------------
+
+None
+
+REST API impact
+---------------
+
+None
+
+Security impact
+---------------
+
+None
+
+
+Notifications impact
+--------------------
+
+None
+
+
+Other end user impact
+---------------------
+
+None
+
+
+Performance Impact
+------------------
+
+This periodically calls Kubernetes-api based on the value of monitoring_interval.
+
+
+Other deployer impact
+---------------------
+
+"kubernetes" is added to masakari-monitors configuration as the new host.monitoring_driver
+type for kubernetes-native openstack operator
+
+
+Developer impact
+----------------
+
+None
+
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+
+Primary assignee:
+* do-gyun kim <dogyun7949@gmail.com>
+
+
+Work Items
+----------
+
+* Create a new monitoring driver using the kubernetes-client.
+
+* Update docs about host monitors.
+
+* Add unit tests.
+
+
+Dependencies
+============
+
+This feature require python kubernetes-client library.
+
+
+Testing
+=======
+
+Add required unit tests which will run in gate.
+
+
+Documentation Impact
+====================
+
+Update masakari-hostmonitor reference documentation.
+
+
+References
+==========
+
+None
+
+
+History
+=======
+
+.. list-table:: Revisions
+   :header-rows: 1
+
+   * - Release Name
+     - Description
+   * - 2024.1 Caracal
+     - Introduced