Spec: V1 API rating modules endpoints migration to V2 API

See migrate_v1_rating_modules_api_endpoints_to_v2.rst for details.

Change-Id: Ic52d0162b478ebcd353e2e3fbf224937222d816e
Story: 2006572
Task: 36679

doc/source/index.rst

@@ -4,6 +4,15 @@
 Cloudkitty Project Specifications
 =================================
 
+Ussuri
+======
+
+.. toctree::
+   :glob:
+   :maxdepth: 1
+
+   specs/ussuri/*
+
 Train
 =====
 
@@ -43,6 +52,7 @@ Ocata
 
    specs/ocata/*
 
+
 ==================
 Indices and tables
 ==================

specs/ussuri/migrate_v1_rating_modules_api_endpoints_to_v2.rst

@@ -0,0 +1,182 @@
+..
+ This work is licensed under a Creative Commons Attribution 3.0 Unported
+ License.
+
+ http://creativecommons.org/licenses/by/3.0/legalcode
+
+===================================================
+V1 API rating modules endpoints migration to V2 API
+===================================================
+
+https://storyboard.openstack.org/#!/story/2006572
+
+With the v1 API being frozen, migrating endpoints that are not present in the v2
+API is required to achieve a complete v2 API with both existing v1 features and
+new v2 ones. This spec is about the ``/v1/rating/modules`` endpoints.
+
+Problem Description
+===================
+
+As the v1 API is planned to be deprecated, ``/v1/rating/modules`` endpoints must
+be ported to v2. The motivation for the v2 API is documented in the relevant
+spec_.
+
+.. _spec: https://specs.openstack.org/openstack/cloudkitty-specs/specs/stein/adding_a_v2_api_to_cloudkitty.html
+
+
+Proposed Change
+===============
+
+Implementing the existing ``/v1/rating/modules`` into the v2 API. This is part of
+the broader effort to migrate v1 endpoints to the v2 API.
+
+Alternatives
+------------
+
+None.
+
+Data model impact
+-----------------
+
+None.
+
+REST API impact
+---------------
+
+This will add ``/v2/rating/modules`` endpoints similarly to the v1 API.
+
+``GET /v2/rating/modules`` returns the list of loaded modules. It does not require
+any parameter. The body of the response will contain the module list:
+
+.. code-block:: javascript
+
+   {
+     "modules": [
+       {
+           "module_id": "f6f4f726-583z-4a09-a972-c908dea4c291"
+           "description": "Sample extension.",
+           "enabled": true,
+           "hot-config": false,
+           "priority": 2
+       },
+       [...]
+     ]
+   }
+
+
+``GET /v2/rating/modules/<module_id>`` returns the module specified by the id in
+the url. It does not need any parameter. The body of the response contains a
+single module:
+
+.. code-block:: javascript
+
+   {
+      "module_id": "f6f4f726-583z-4a09-a972-c908dea4c291",
+      "description": "Sample extension.",
+      "enabled": true,
+      "hot-config": false,
+      "priority": 2
+   }
+
+
+``PUT /v2/rating/modules/<module_id>`` changes the state and priority of a module.
+It requires fields to be updated to be present in the query body:
+
+.. code-block:: javascript
+
+   {
+     "enabled": false,
+     "priority": 42
+   }
+
+For both GET endpoints, the expected response code is a 200 OK.
+For the PUT endpoint, the expected response is a 204 NO CONTENT as the body is
+empty.
+Expected HTTP error response codes for all 3 endpoints are:
+
+* ``400 Bad Request``: Malformed request.
+
+* ``401 Unauthorized``: The user is not authenticated.
+
+* ``403 Forbidden``: The user is not authorized.
+
+
+
+Security impact
+---------------
+
+All added endpoints will keep the same policy as the v1 API: admin credentials
+are needed to query the API endpoints. Added endpoints only port existing
+functionality from v1 to v2 API and will not have any other security impact.
+
+Notifications Impact
+--------------------
+
+A notification reload triggered by queries on added endpoints is planned in
+the future.
+
+Other end user impact
+---------------------
+
+None.
+
+
+Performance Impact
+------------------
+
+None.
+
+Other deployer impact
+---------------------
+
+None.
+
+Developer impact
+----------------
+
+None.
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+
+
+Primary assignee:
+  qanglade/qanglade
+Other contributors:
+  lukapeschke/peschk_l
+
+
+Work Items
+----------
+
+* Implement the ``/v1/rating/modules`` endpoints in the v2 API, including
+  unit tests and documentation
+
+* Add functional tests to the tempest plugin
+
+* Add support to CloudKitty's client
+
+Dependencies
+============
+
+None.
+
+Testing
+=======
+
+Besides regular unit tests, the tempest plugin will be updated to add new tests
+for added endpoints.
+
+
+Documentation Impact
+====================
+
+v2 API reference will be updated to reflect changes.
+
+References
+==========
+
+None.