Implemented GMR plugin to show CDM structures

In this changeset, I implemented a small GMR plugin that converts
the cluster data model structure into an XML structure.

Change-Id: I75548952635a0aa3c7dbd6d068831b5765a5db1a
Closes-Bug: #1620551

watcher/decision_engine/gmr.py

@@ -0,0 +1,48 @@
+# -*- encoding: utf-8 -*-
+# Copyright (c) 2016 b<>com
+#
+# Authors: Vincent FRANCOISE <vincent.francoise@b-com.com>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from oslo_reports import guru_meditation_report as gmr
+
+from watcher._i18n import _
+from watcher.decision_engine.model.collector import manager
+
+
+def register_gmr_plugins():
+    """Register GMR plugins that are specific to watcher-decision-engine."""
+    gmr.TextGuruMeditation.register_section(_('CDMCs'), show_models)
+
+
+def show_models():
+    """Create a formatted output of all the CDMs
+
+    Mainly used as a Guru Meditation Report (GMR) plugin
+    """
+    mgr = manager.CollectorManager()
+
+    output = []
+    for name, cdmc in mgr.get_collectors().items():
+        output.append("")
+        output.append("~" * len(name))
+        output.append(name)
+        output.append("~" * len(name))
+        output.append("")
+
+        cdmc_struct = cdmc.cluster_data_model.to_string()
+        output.append(cdmc_struct)
+
+    return "\n".join(output)

watcher/decision_engine/model/model_root.py

@@ -14,6 +14,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import collections
+
+from lxml import etree
 import six
 
 from watcher._i18n import _
@@ -159,3 +162,61 @@ class ModelRoot(object):
 
     def get_resource_from_id(self, resource_id):
         return self.resource[str(resource_id)]
+
+    def get_node_instances(self, node):
+        return self.mapping.get_node_instances(node)
+
+    def _build_compute_node_element(self, compute_node):
+        attrib = collections.OrderedDict(
+            uuid=compute_node.uuid, human_id=compute_node.human_id,
+            hostname=compute_node.hostname, state=compute_node.state,
+            status=compute_node.status)
+
+        for resource_name, resource in self.resource.items():
+            res_value = resource.get_capacity(compute_node)
+            if res_value is not None:
+                attrib[resource_name] = six.text_type(res_value)
+
+        compute_node_el = etree.Element("ComputeNode", attrib=attrib)
+
+        return compute_node_el
+
+    def _build_instance_element(self, instance):
+        attrib = collections.OrderedDict(
+            uuid=instance.uuid, human_id=instance.human_id,
+            hostname=instance.hostname, state=instance.state)
+
+        for resource_name, resource in self.resource.items():
+            res_value = resource.get_capacity(instance)
+            if res_value is not None:
+                attrib[resource_name] = six.text_type(res_value)
+
+        instance_el = etree.Element("Instance", attrib=attrib)
+
+        return instance_el
+
+    def to_string(self):
+        root = etree.Element("ModelRoot")
+        # Build compute node tree
+        for cn in sorted(self.get_all_compute_nodes().values(),
+                         key=lambda cn: cn.uuid):
+            compute_node_el = self._build_compute_node_element(cn)
+
+            # Build mapped instance tree
+            node_instance_uuids = self.get_node_instances(cn)
+            for instance_uuid in sorted(node_instance_uuids):
+                instance = self.get_instance_from_id(instance_uuid)
+                instance_el = self._build_instance_element(instance)
+                compute_node_el.append(instance_el)
+
+            root.append(compute_node_el)
+
+        # Build unmapped instance tree (i.e. not assigned to any compute node)
+        for instance in sorted(self.get_all_instances().values(),
+                               key=lambda inst: inst.uuid):
+            try:
+                self.get_node_from_instance_id(instance.uuid)
+            except exception.InstanceNotFound:
+                root.append(self._build_instance_element(instance))
+
+        return etree.tostring(root, pretty_print=True).decode('utf-8')

watcher/decision_engine/strategy/strategies/basic_consolidation.py

@@ -252,11 +252,11 @@ class BasicConsolidation(base.ServerConsolidationBaseStrategy):
         :rtype: float
         """
         resource_id = "%s_%s" % (node.uuid, node.hostname)
-        host_avg_cpu_util = self.ceilometer. \
-            statistic_aggregation(resource_id=resource_id,
-                                  meter_name=self.HOST_CPU_USAGE_METRIC_NAME,
-                                  period="7200",
-                                  aggregate='avg')
+        host_avg_cpu_util = self.ceilometer.statistic_aggregation(
+            resource_id=resource_id,
+            meter_name=self.HOST_CPU_USAGE_METRIC_NAME,
+            period="7200",
+            aggregate='avg')
 
         if host_avg_cpu_util is None:
             LOG.error(
@@ -269,7 +269,7 @@ class BasicConsolidation(base.ServerConsolidationBaseStrategy):
         cpu_capacity = self.compute_model.get_resource_from_id(
             element.ResourceType.cpu_cores).get_capacity(node)
 
-        total_cores_used = cpu_capacity * (host_avg_cpu_util / 100)
+        total_cores_used = cpu_capacity * (host_avg_cpu_util / 100.0)
 
         return self.calculate_weight(node, total_cores_used, 0, 0)