==========================
Valence Ironic Integration
==========================
This proposal describes the integration of projects Valence and
OpenStack Baremetal Service, Ironic.

Problem description
===================
Valence allows to compose nodes out of a pool of disaggregated hardware.
And Ironic allows to provision bare metal machines. Once the node is
composed by Valence that can be registered to Ironic to be consumed.
So this feature aims on providing a way to integrate Valence and Ironic,
so that users will be able to provision bare metal machines on the composed
nodes by Ironic.

Proposed change
===============
To enable Valence to be able to register its composed node to Ironic, we
will add a new API endpoint /v1/nodes/{ID}/register. The detailed explanation
of this API is as below:

1. Add a new Valence /v1/nodes/{ID}/register API
This introduces a new nodes API in valence that will be used to register a
composed node in Ironic. Below steps explains a detailed flow of registering
a node from Valence to Ironic.

Step 1: User calls Valence APIs to register a node.

    $ valence node-register test-node
    This API will register the test-node to Ironic.

NOTE: Once the node is registered to Ironic, no further actions like deleting
the node, changing the boot device will be supported by Valence. Admin can use
the Ironic APIs to perform these actions.

Step 2: Valence calls Ironic API internally to register this node which is equivalent to:

    $ ironic node-create –d redfish –i redfish_root_uri <Redfish URL> -i refish_username <username> ...
    This will create a new node in Ironic with all the required details related
    to Redfish. It will also create a port in Ironic with the node's MAC address.

After the node is succesfully registered to Ironic, users can use the Ironic or
Nova to install an OS on the node.

Also we will add another API endpoint /v1/nodes/{ID}/unregister to delete the node from Ironic.


Alternatives
------------
None


Data model impact
-----------------
Add a new field 'managed_by' in Nodes DB.


REST API impact
---------------
1. Add a new API endpoint /v1/node/{ID}/register
1. Add a new API endpoint /v1/node/{ID}/unregister

Driver API impact
-----------------
1. Add a new driver that can be used to interact with ironic.


Security impact
---------------
None

Other end user impact
---------------------
None

Scalability impact
------------------
None

Performance Impact
------------------
None

Other deployer impact
---------------------
None

Developer impact
----------------
None

Implementation
==============
Assignee(s)
-----------
Primary assignee:
  Madhuri Kumari

Work Items
----------
* Add a driver in Valence to interact with Ironic.
* Add a new field 'managed_by' in Nodes DB.
* Add new API endpoint /v1/node/{ID}/register.
* Add new API endpoint /v1/node/{ID}/unregister.
* Update api-ref to include the new API.

Dependencies
============
Depends on Ironic project. python-ironicclient needs to be
added to the project's requirement.

Testing
=======
* Each patch will be accompanied with unit testcases.

Documentation Impact
====================
Update document to include the details of new node register API.

References
==========
None