Support OS::Aodh::CompositeAlarm resource

We have deprecated combination alarm, and this blueprint
to support composite alarm which is similar with the
combination alarm in functionality.

Change-Id: I6a8b7c6752229353208b7d8e9ef1b1d90670f570
Blueprint: add-aodh-composite-alarm

specs/ocata/support-aodh-composite-alarm.rst

@@ -0,0 +1,163 @@
+..
+ This work is licensed under a Creative Commons Attribution 3.0 Unported
+ License.
+
+ http://creativecommons.org/licenses/by/3.0/legalcode
+
+..
+ This template should be in ReSTructured text. The filename in the git
+ repository should match the launchpad URL, for example a URL of
+ https://blueprints.launchpad.net/heat/+spec/awesome-thing should be named
+ awesome-thing.rst .  Please do not delete any of the sections in this
+ template.  If you have nothing to say for a whole section, just write: None
+ For help with syntax, see http://sphinx-doc.org/rest.html
+ To test out your formatting, see http://www.tele3.cz/jbar/rest/rest.html
+
+====================================
+Support aodh composite alarm in heat
+====================================
+
+https://blueprints.launchpad.net/heat/+spec/add-aodh-composite-alarm
+
+Adds resource plugin for Aodh composite alarm.
+
+Problem description
+===================
+
+The combination type alarm has been deprecated in aodh, because some issues
+which are hard to solved. And we have deprecated OS::Aodh::CombinationAlarm
+synchronously, see:
+
+https://blueprints.launchpad.net/heat/+spec/migrate-to-use-aodh-for-alarms
+
+It's recommended to use composite rule alarm which is similar with the
+combination alarm in functionality.
+
+
+Proposed change
+===============
+
+Add the following resource under resources/openstack/aodh/
+
+* OS::Aodh::CompositeAlarm
+
+    * description
+        Description of the alarm.
+        - optional
+        - type: String
+        - update_allowed
+    * severity
+        Severity of the alarm.
+        - optional
+        - type: Integer
+        - update_allowed
+        - constraints: one of ['low', 'moderate', 'critical']
+        - default: low
+    * enabled
+        True if alarm evaluation is enabled.
+        - optional
+        - type: Boolean
+        - update_allowed
+        - default: True
+    * alarm_actions
+        A list of URLs (webhooks) to invoke when state transitions to alarm.
+        - optional
+        - type: List
+        - update_allowed
+    * ok_actions
+        A list of URLs (webhooks) to invoke when state transitions to ok.
+        - optional
+        - type: List
+        - update_allowed
+    * insufficient_data_actions
+        A list of URLs (webhooks) to invoke when state transitions to
+        insufficient-data.
+        - optional
+        - type: List
+        - update_allowed
+    * repeat_actions
+        True if actions should be repeatedly notified while alarm remains
+        in target state.
+        - optional
+        - type: Boolean
+        - update_allowed
+        - default: True
+    * time_constraints
+        Describe time constraints for the alarm.
+        - optional
+        - type: List
+    * composite_rule
+        Composite threshold rule with JSON format.
+        - required
+        - type: Map
+        - update_allowed
+        - schema: {'operator': 'or'/'and', 'rules': [rule1, rule2...]}
+
+The following is an example of composite alarm::
+
+  Resources:
+    my_composite_alarm:
+      type: OS::Aodh::CompositeAlarm
+      properties:
+        composite_rule:
+          operator: or
+          rules:
+          - type: threshold
+            meter_name: cpu_util
+            evaluation_periods: 1
+            period: 60
+            statistic: avg
+            threshold: 0.8
+            comparison_operator: ge
+            exclude_outliers: false
+          - and:
+            - type: threshold
+              meter_name: disk.usage
+              evaluation_periods: 1
+              period: 60
+              statistic: avg
+              threshold: 0.8
+              comparison_operator: ge
+              exclude_outliers: false
+            - type: threshold
+              meter_name: mem_util
+              evaluation_periods: 1
+              period: 60
+              statistic: avg
+              threshold: 0.8
+              comparison_operator: ge
+              exclude_outliers: false
+        description: a composite alarm
+        ...... (other properties)
+
+Alternatives
+------------
+None
+
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+
+Primary assignee:
+    huangtianhua@huawei.com
+
+Milestones
+----------
+Target Milestone for completion:
+  ocata-1
+
+Work Items
+----------
+
+* Add OS::Aodh::CompositeAlarm resource
+* Add related tests
+* Add sample template using OS::Aodh::CompositeAlarm in heat-templates
+
+
+Dependencies
+============
+
+None