Add a force field to audit

As now, Watcher doesn't allow to launch a new audit when there
is actionplan ongoing. This patch gives the choice to User,
if User set force when launching audit, Watcher will execute the
audit even other actionplan is ongoing.

Change-Id: I276ebcee0b09bfc6f27ec39f43ba2ecd230db2b2
Implements: blueprint add-force-field-to-audit

specs/train/approved/add-force-field-to-audit.rst

@@ -0,0 +1,191 @@
+..
+ This work is licensed under a Creative Commons Attribution 3.0 Unported
+ License.
+
+ http://creativecommons.org/licenses/by/3.0/legalcode
+
+========================
+Add force field to Audit
+========================
+
+https://blueprints.launchpad.net/watcher/+spec/add-force-field-to-audit
+
+
+Problem description
+===================
+
+As now, Watcher doesn't allow to launch a new audit when there
+is actionplan ongoing. This is because if the new audit has
+the same data model as the ongoing actionplan, the new audit
+may create a wrong actionplan. But if there are different data
+model scope, we should allow the new audit to run.
+
+Use Cases
+----------
+
+As a Watcher user, I want to launch audit despite of ongoing actionplan.
+
+
+Proposed change
+===============
+
+We need to add a new field **force** in audit table. If **force** is True,
+Watcher will execute the audit even other actionplan is ongoing.
+
+.. code-block:: python
+
+    def pre_execute(self, audit, request_context):
+        LOG.debug("Trigger audit %s", audit.uuid)
+        if audit.force is False:
+            self.check_ongoing_action_plans(request_context)
+        # Write hostname that will execute this audit.
+        audit.hostname = CONF.host
+        # change state of the audit to ONGOING
+        self.update_audit_state(audit, objects.audit.State.ONGOING)
+
+The default value is False.
+We also need to add an option in the post audit API. So that User can set
+the value of the **force** field.
+CLI example for creating audit with force:
+
+.. code-block:: bash
+
+   $ watcher audit create -g dummy --force
+
+
+Alternatives
+------------
+
+None
+
+Data model impact
+-----------------
+
+Add new **force** field in the audit table
+
+REST API impact
+---------------
+
+Need to add new **force** parameter in Audits APIs.
+
+Security impact
+---------------
+
+None
+
+Notifications impact
+--------------------
+
+Add **force** to AuditPayload
+
+**audit.create**
+
+.. code-block:: python
+
+    {
+      "priority": "INFO",
+      "payload": {
+        "watcher_object.data": {
+          "audit_type": "ONESHOT",
+          "parameters": {
+            "para2": "hello",
+            "para1": 3.2
+          },
+          "state": "PENDING",
+          "updated_at": null,
+          "deleted_at": null,
+          "interval": null,
+          "scope": [],
+          "force": False,
+          "created_at": "2016-11-04T16:29:20Z",
+          "uuid": "4a97b9dd-2023-43dc-b713-815bdd94d4d6"
+         },
+        "watcher_object.name": "AuditCreatePayload",
+        "watcher_object.version": "1.0",
+        "watcher_object.namespace": "watcher"
+      },
+      "publisher_id": "infra-optim:localhost",
+      "timestamp": "2016-11-04 16:31:36.264673   ",
+      "event_type": "audit.create",
+      "message_id": "cbcf9f2c-7c53-4b4d-91ec-db49cca024b6"
+    }
+
+Other end user impact
+---------------------
+
+* Need to add **force** to CLI 'watcher audit create'
+* Also need to update watcher-dashboard
+
+Performance Impact
+------------------
+
+None
+
+Other deployer impact
+---------------------
+
+None
+
+Developer impact
+----------------
+
+None
+
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+
+Primary assignee:
+  licanwei
+
+Work Items
+----------
+
+* Update architecture doc to add the new field
+* Add new **force** field in the audit table
+* Check the value of **force** before running audit
+* Update Watcher API version
+* Update notification AuditPayload
+* Update python-watcherclient
+* Update watcher-dashboard
+
+
+Dependencies
+============
+
+None
+
+
+Testing
+=======
+
+Unittest for all changes
+
+
+Documentation Impact
+====================
+
+Update architecture doc to add the new field.
+
+
+References
+==========
+
+None
+
+
+History
+=======
+
+
+.. list-table:: Revisions
+   :header-rows: 1
+
+   * - Release Name
+     - Description
+   * - Train
+     - Introduced
+