Specs of impelementing root-enable, root-disable in redis.

Implement root-enable, root-disable for redis to manage redis
authentication.

Implements: blueprint root-enable-in-redis
Change-Id: I55301bbfc770431b6eca75042619f5a5ffbf8ada
Signed-off-by: Fan Zhang <zh.f@outlook.com>

doc/source/index.rst

@@ -12,6 +12,14 @@ Contents:
 
    specs/*
 
+Queens approved specs:
+
+.. toctree::
+   :glob:
+   :maxdepth: 1
+
+   specs/queens/*
+
 Ocata approved specs:
 
 .. toctree::

specs/queens/impelment-root-enable-for-redis.rst

@@ -0,0 +1,264 @@
+..
+    This work is licensed under a Creative Commons Attribution 3.0 Unported
+    License.
+
+    http://creativecommons.org/licenses/by/3.0/legalcode
+
+    Sections of this template were taken directly from the Nova spec
+    template at:
+    https://github.com/openstack/nova-specs/blob/master/specs/juno-template.rst
+
+..
+
+
+======================================================
+Implement root-enable/root-disable/root-show for Redis
+======================================================
+
+.. If section numbers are desired, unindent this
+    .. sectnum::
+
+.. If a TOC is desired, unindent this
+    .. contents::
+
+Trove currently has support for enabling root user, disabling root user
+and showing root-enabled status for database instances, but that functionality
+is lacking for redis. This blueprint outlines a framework and API for
+implementing authentication management for redis.
+
+Launchpad Blueprint:
+https://blueprints.launchpad.net/trove/+spec/root-enable-in-redis
+
+
+Problem Description
+===================
+
+Trove does not currently support root-enable, root-disable, root-show for
+redis instances.
+
+
+Proposed Change
+===============
+
+Implement root-enable, root-disable and root-show API for redis. It will
+support two scenarios including redis single instance and redis replica
+instances which these operations only support master instance but can make
+effect on slave instances.
+
+This implementation does not support a cluster of redis instances.
+
+Here are the details:
+
+Root-enable
+-----------
+
+* Precondition checks to make sure that it's not cluster or slave instance to
+  execute this action.
+
+* Get slave instances of given instance.
+
+* Try to get original auth password for the sake of rolling back.
+
+* Do root enable for given instance. Considering it's a single instance or
+  a master of redis replica sets, roll back once using original auth password
+  and raise exception if any error occurs.
+
+* If things go well, and there are some slave instances, get root password and
+  use root password above to do root enable. Get failed slave instances' id
+  if any, store them into a list.
+
+* Return redis root created view alongside the failed slave instances' id list.
+
+Root-disable
+------------
+
+* Precondition checks to make sure that it's not cluster or slave instance to
+  execute this action.
+
+* Get slave instances of given instance.
+
+* Try to get original auth password for the sake of rolling back.
+
+* Do root disable for given instance. Considering it's a single instance or
+  a master of redis replica sets, roll back once using original auth password
+  and raise exception if any error occurs.
+
+* If things go well, and there are some slave instances, do root disable. Get
+  failed slave instances' id if any, store them into a list.
+
+* If there are any failed slaves, return http code 200 with failed slaves list.
+  If not, just return None with http code 204.
+
+Root-show
+---------
+
+Using root-show of mysql. It can satisfy what we ask for.
+
+Configuration
+-------------
+
+Changing the follow configuration value:
+
+.. code-block:: python
+
+    cfg.StrOpt('root_controller',
+               default='trove.extensions.redis.service.RedisRootController',
+               help='Root controller implementation for redis.'),
+
+
+Remove requirepass in trove/templates/redis/validation-rules.json to avoid
+modifying authentication by configuration group.
+
+Database
+--------
+
+None
+
+Public API
+----------
+
+Change the return contents of root-enable and root-disable. Since redis does
+not have a root user, just show '-' as user name. Return failed slaves if any.
+For example:
+
+.. code-block:: python
+
+    {
+        "failed_slaves": [
+            "67c2f6d6-7c01-4ce9-bb18-aa951ca5a39b"
+        ],
+        "user": {
+            "password": "bdQhBXVpk7TE689aGgqdNmJmg4qHdpdBegae",
+            "name": "-"
+        }
+    }
+
+Public API Security
+-------------------
+
+None
+
+Python API
+----------
+
+None
+
+CLI (python-troveclient)
+------------------------
+
+Change the return content to meet API above.
+
+Internal API
+------------
+
+None
+
+Guest Agent
+-----------
+
+The work will require some implementation of the guest manager:
+
+* Add requirepass and masterauth into redis.conf when executing root enable,
+  and apply overrides to bring into effect without restarting redis service.
+  Rebuild admin client to make sure guest agent can still talk to task manager
+  after adding enabling/disabling root in redis, which has been done in this
+  patch [1]_.
+
+* Remove requirepass and masterauth in redis.conf when executing root disable,
+  and apply overrides to bring into effect without restarting redis service.
+  Still, rebuild admin client.
+
+
+Alternatives
+------------
+
+We can achieve authentication management for redis by configuration group, but
+it looks like less convenient than using root-enable and root-disable.
+
+
+Dashboard Impact (UX)
+=====================
+
+None
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+
+Primary assignee:
+  fanzhang <zh.f@outlook.com>
+
+Milestones
+----------
+
+Target Milestone for completion:
+  Queens-Q2
+
+
+Work Items
+----------
+
+* Implement redis root controller, service, models and views.
+
+* Implement redis guest agent, including manager, service and models.
+
+
+Upgrade Implications
+====================
+
+None
+
+
+Dependencies
+============
+
+None
+
+
+Testing
+=======
+
+Inside the int_tests.py, root_actions_groups will be added to redis supported
+groups in order to reuse some scenario tests with proper modification to meet
+the root actions functionality of redis.
+
+Unittests will be added to test the derived controller functionality, for
+example:
+
+* Test root-enable on single redis instance.
+
+* Test root-enable on master instance of redis replication.
+
+* Test root-enable on slave instance of redis replication.
+
+* Test root-enable with is_cluster=True.
+
+* Test root-delete in the cases of above.
+
+Unittests will be also added to test the implemented functions inside guest-
+agent including enable_root and disable_root.
+
+
+Documentation Impact
+====================
+
+The documentation [2]_ should be updated to add the following features:
+
+* Successful response examples of enabling/disabling root in redis.
+
+* Failed response examples of enabling/disabling root in redis.
+
+But it is not mandatory to add.
+
+References
+==========
+
+.. [1] https://bugs.launchpad.net/trove/+bug/1708376
+.. [2] https://developer.openstack.org/api-ref/database/#users-users
+
+Appendix
+========
+
+None.