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+..
+ This work is licensed under a Creative Commons Attribution 3.0 Unported
+ License.
+
+ http://creativecommons.org/licenses/by/3.0/legalcode
+
+==========================================
+Define a tailored Scoper for each CDM
+==========================================
+
+https://blueprints.launchpad.net/watcher/+spec/cdm-scoping
+
+Problem description
+===================
+
+Storage cluster data model was introduced in Pike cycle. Since the model is
+different from compute data model, current single CDM scoper does not work
+for the model.
+
+Use Cases
+----------
+
+As a Watcher user, I want to restrict scope of storage cluster data model.
+
+Proposed change
+===============
+
+* Add _audit_scope instance attribute to the BaseClusterDataModelCollector
+  and initialize when instantiated.
+
+* Remove audit_scope_handler from the current BaseStrategy and move it within
+  the BaseClusterDataModelCollector.
+
+* Add audit_scope argument to CollectorManager's get_cluster_model_collector
+  method.
+
+* Change compute_model method to use Collector's audit_scope_handler.
+
+* Change original DefaultScope.
+
+  * get_scoped_model simply returns cluster_model.
+
+  * For representing multi data model for JSON shema, we change DEFAULT_SCHEMA
+    as the following::
+
+      DEFAULT_SCHEMA = {
+          "$schema": "http://json-schema.org/draft-04/schema#",
+          "type": "object",
+          "properties": {
+              "compute": {
+                  # current JSON schema moved to NovaClusterDataModelCollector
+                  # retrieved from NovaClusterDataModelCollector
+              },
+              "storage": {
+                  # retrieved from CinderClusterDatamodelCollector
+              },
+              .......
+          }
+      }
+
+    Properties are dynamically retrieved from collector plugins.
+
+  * Update validate method in AuditTemplatePostType in accordance with the
+    above change.
+
+* Rename the DefaultScope as ComputeScope and override the audit_scope_handler
+  property in the Compute Collector.
+
+* Change audit template help message in python-watcherclient.
+
+Alternatives
+------------
+
+None
+
+Data model impact
+-----------------
+
+None
+
+REST API impact
+---------------
+
+Scope JSON schema definition for the audit template POST data from
+the request body will be changed in accordance with DEFAULT_SCHEMA change.
+
+Security impact
+---------------
+
+None
+
+Notifications impact
+--------------------
+
+None
+
+Other end user impact
+---------------------
+
+End user defines audit scope in each audit template by specifying yaml or json
+file with --scope option. The file format will be changed according to JSON
+schema change.
+
+Performance Impact
+------------------
+
+None
+
+Other deployer impact
+---------------------
+
+None
+
+Developer impact
+----------------
+
+None
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+
+Primary assignee:
+  <nakamura-h>
+
+Other contributors:
+  <None>
+
+Work Items
+----------
+
+* Add or remove audit_scope and audit_scope_handler from/to base classes.
+
+* Change original DefaultScope.
+
+* Change Compute Collector to use ComputeScope instead of DefaultScope.
+
+* Change python-watcherclient.
+
+Dependencies
+============
+
+None
+
+Testing
+=======
+
+Unit test will be updated.
+
+Documentation Impact
+====================
+
+None, but it is preferable to adding more.
+
+References
+==========
+
+* https://blueprints.launchpad.net/watcher/+spec/cinder-model-integration