Add cpu util to MesosMonitor

Cpu metric is important to a clutser, add cpu util to notification bus.

After this patch get applied, we will get following metrics:

{'metrics': [{'unit': '%', 'name': 'cpu_util', 'value': 30.0}, {'unit':
    '%', 'name': 'memory_util', 'value': 4.795204795204795}]

Change-Id: I44cc2edf2a33ff2991ba0b006d802dc3efee42b6

magnum/conductor/mesos_monitor.py

@@ -29,6 +29,10 @@ class MesosMonitor(MonitorBase):
                 'unit': '%',
                 'func': 'compute_memory_util',
             },
+            'cpu_util': {
+                'unit': '%',
+                'func': 'compute_cpu_util',
+            },
         }
 
     def _build_url(self, url, protocol='http', port='80', path='/'):
@@ -40,6 +44,8 @@ class MesosMonitor(MonitorBase):
     def pull_data(self):
         self.data['mem_total'] = 0
         self.data['mem_used'] = 0
+        self.data['cpu_total'] = 0
+        self.data['cpu_used'] = 0
         for master_addr in self.bay.master_addresses:
             mesos_master_url = self._build_url(master_addr, port='5050',
                                                path='/state')
@@ -48,10 +54,18 @@ class MesosMonitor(MonitorBase):
                 for slave in master['slaves']:
                     self.data['mem_total'] += slave['resources']['mem']
                     self.data['mem_used'] += slave['used_resources']['mem']
+                    self.data['cpu_total'] += slave['resources']['cpus']
+                    self.data['cpu_used'] += slave['used_resources']['cpus']
                 break
 
     def compute_memory_util(self):
-        if self.data['mem_total'] == 0:
+        if self.data['mem_total'] == 0 or self.data['mem_used'] == 0:
             return 0
         else:
             return self.data['mem_used'] * 100 / self.data['mem_total']
+
+    def compute_cpu_util(self):
+        if self.data['cpu_used'] == 0:
+            return 0
+        else:
+            return self.data['cpu_used'] * 100 / self.data['cpu_total']

magnum/tests/unit/conductor/test_monitors.py

@@ -219,7 +219,7 @@ class MonitorsTestCase(base.TestCase):
 
     def _test_mesos_monitor_pull_data(
             self, mock_url_get, state_json, expected_mem_total,
-            expected_mem_used):
+            expected_mem_used, expected_cpu_total, expected_cpu_used):
         state_json = jsonutils.dumps(state_json)
         mock_url_get.return_value = state_json
         self.mesos_monitor.pull_data()
@@ -227,6 +227,10 @@ class MonitorsTestCase(base.TestCase):
                          expected_mem_total)
         self.assertEqual(self.mesos_monitor.data['mem_used'],
                          expected_mem_used)
+        self.assertEqual(self.mesos_monitor.data['cpu_total'],
+                         expected_cpu_total)
+        self.assertEqual(self.mesos_monitor.data['cpu_used'],
+                         expected_cpu_used)
 
     @mock.patch('magnum.common.urlfetch.get')
     def test_mesos_monitor_pull_data_success(self, mock_url_get):
@@ -235,14 +239,17 @@ class MonitorsTestCase(base.TestCase):
             'pid': 'master@10.0.0.6:5050',
             'slaves': [{
                 'resources': {
-                    'mem': 100
+                    'mem': 100,
+                    'cpus': 1,
                 },
                 'used_resources': {
-                    'mem': 50
+                    'mem': 50,
+                    'cpus': 0.2,
                 }
             }]
         }
-        self._test_mesos_monitor_pull_data(mock_url_get, state_json, 100, 50)
+        self._test_mesos_monitor_pull_data(mock_url_get, state_json,
+                                           100, 50, 1, 0.2)
 
     @mock.patch('magnum.common.urlfetch.get')
     def test_mesos_monitor_pull_data_success_not_leader(self, mock_url_get):
@@ -251,12 +258,13 @@ class MonitorsTestCase(base.TestCase):
             'pid': 'master@1.1.1.1:5050',
             'slaves': []
         }
-        self._test_mesos_monitor_pull_data(mock_url_get, state_json, 0, 0)
+        self._test_mesos_monitor_pull_data(mock_url_get, state_json,
+                                           0, 0, 0, 0)
 
     @mock.patch('magnum.common.urlfetch.get')
     def test_mesos_monitor_pull_data_success_no_master(self, mock_url_get):
         self.bay.master_addresses = []
-        self._test_mesos_monitor_pull_data(mock_url_get, {}, 0, 0)
+        self._test_mesos_monitor_pull_data(mock_url_get, {}, 0, 0, 0, 0)
 
     def test_mesos_monitor_get_metric_names(self):
         mesos_metric_spec = 'magnum.conductor.mesos_monitor.MesosMonitor.'\
@@ -292,3 +300,29 @@ class MonitorsTestCase(base.TestCase):
         self.mesos_monitor.data = test_data
         mem_util = self.mesos_monitor.compute_memory_util()
         self.assertEqual(0, mem_util)
+
+        test_data = {
+            'mem_total': 100,
+            'mem_used': 0,
+            'pods': 0,
+        }
+        self.mesos_monitor.data = test_data
+        mem_util = self.mesos_monitor.compute_memory_util()
+        self.assertEqual(0, mem_util)
+
+    def test_mesos_monitor_compute_cpu_util(self):
+        test_data = {
+            'cpu_total': 1,
+            'cpu_used': 0.2,
+        }
+        self.mesos_monitor.data = test_data
+        cpu_util = self.mesos_monitor.compute_cpu_util()
+        self.assertEqual(20, cpu_util)
+
+        test_data = {
+            'cpu_total': 100,
+            'cpu_used': 0,
+        }
+        self.mesos_monitor.data = test_data
+        cpu_util = self.mesos_monitor.compute_cpu_util()
+        self.assertEqual(0, cpu_util)