timedelta plugin for meter definition process

with timedelta plugin we could create new metric for latency time of
nstance booting without using events and its transformation.
we could define new meter in meters.yaml with volume as in example::
   volume:
      fields: [$.payload.created_at, $.payload.launched_at]
      plugin: ‘timedelta’

as a result we get volume value equal to difference between two mentioned
timestamp fields in seconds.

Change-Id: If5084cc23212a0a6bd9dac8438d5d286f3415730

ceilometer/event/trait_plugins.py

@@ -17,6 +17,7 @@ import abc
 
 from debtcollector import moves
 from oslo_log import log
+from oslo_utils import timeutils
 import six
 
 from ceilometer.i18n import _LW
@@ -188,3 +189,42 @@ class BitfieldTraitPlugin(TraitPluginBase):
                 else:
                     bitfield |= bit
         return [bitfield]
+
+
+class TimedeltaPluginMissedFields(Exception):
+    def __init__(self):
+        msg = ('It is required to use two timestamp field with Timedelta '
+               'plugin.')
+        super(TimedeltaPluginMissedFields, self).__init__(msg)
+
+
+class TimedeltaPlugin(TraitPluginBase):
+    """Setup timedelta meter volume of two timestamps fields.
+
+    Example::
+
+        trait's fields definition: ['payload.created_at',
+                                    'payload.launched_at']
+        value is been created as total seconds between 'launched_at' and
+        'created_at' timestamps.
+    """
+    # TODO(idegtiarov): refactor code to have meter_plugins separate from
+    # trait_plugins
+
+    def trait_value(self, match_list):
+        if len(match_list) != 2:
+            LOG.warning(_LW('Timedelta plugin is required two timestamp fields'
+                            ' to create timedelta value.'))
+            return
+        start, end = match_list
+        try:
+            start_time = timeutils.parse_isotime(start[1])
+            end_time = timeutils.parse_isotime(end[1])
+        except Exception as err:
+            LOG.warning(_LW('Failed to parse date from set fields, both '
+                            'fields %(start)s and %(end)s must be datetime: '
+                            '%(err)s') %
+                        dict(start=start[0], end=end[0], err=err)
+                        )
+            return
+        return abs((end_time - start_time).total_seconds())

ceilometer/meter/data/meters.yaml

@@ -107,6 +107,16 @@ metric:
     project_id: $.payload.tenant_id
     resource_id: $.payload.instance_id
 
+  - name: 'compute.instance.booting.time'
+    event_type: 'compute.instance.create.end'
+    type: 'gauge'
+    unit: 'sec'
+    volume:
+      fields: [$.payload.created_at, $.payload.launched_at]
+      plugin: 'timedelta'
+    project_id: $.payload.tenant_id
+    resource_id: $.payload.instance_id
+
   - name: 'disk.root.size'
     event_type: 'compute.instance.*'
     type: 'gauge'

ceilometer/tests/unit/meter/test_meter_plugins.py

@@ -0,0 +1,71 @@
+#
+# Copyright 2016 Mirantis Inc.
+#
+# 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.
+import mock
+from oslotest import base
+
+from ceilometer.event import trait_plugins
+
+
+class TestTimedeltaPlugin(base.BaseTestCase):
+
+    def setUp(self):
+        super(TestTimedeltaPlugin, self).setUp()
+        self.plugin = trait_plugins.TimedeltaPlugin()
+
+    def test_timedelta_transformation(self):
+        match_list = [('test.timestamp1', '2016-03-02T15:04:32'),
+                      ('test.timestamp2', '2016-03-02T16:04:32')]
+        value = self.plugin.trait_value(match_list)
+        self.assertEqual(3600, value)
+
+    def test_timedelta_missing_field(self):
+        match_list = [('test.timestamp1', '2016-03-02T15:04:32')]
+        with mock.patch('%s.LOG' % self.plugin.trait_value.__module__) as log:
+            self.assertIsNone(self.plugin.trait_value(match_list))
+            log.warning.assert_called_once_with(
+                'Timedelta plugin is required two timestamp fields to create '
+                'timedelta value.')
+
+    def test_timedelta_exceed_field(self):
+        match_list = [('test.timestamp1', '2016-03-02T15:04:32'),
+                      ('test.timestamp2', '2016-03-02T16:04:32'),
+                      ('test.timestamp3', '2016-03-02T16:10:32')]
+        with mock.patch('%s.LOG' % self.plugin.trait_value.__module__) as log:
+            self.assertIsNone(self.plugin.trait_value(match_list))
+            log.warning.assert_called_once_with(
+                'Timedelta plugin is required two timestamp fields to create '
+                'timedelta value.')
+
+    def test_timedelta_invalid_timestamp(self):
+        match_list = [('test.timestamp1', '2016-03-02T15:04:32'),
+                      ('test.timestamp2', '2016-03-02T15:004:32')]
+        with mock.patch('%s.LOG' % self.plugin.trait_value.__module__) as log:
+            self.assertIsNone(self.plugin.trait_value(match_list))
+            msg = log.warning._mock_call_args[0][0]
+            self.assertTrue(msg.startswith('Failed to parse date from set '
+                                           'fields, both fields ')
+                            )
+
+    def test_timedelta_reverse_timestamp_order(self):
+        match_list = [('test.timestamp1', '2016-03-02T15:15:32'),
+                      ('test.timestamp2', '2016-03-02T15:10:32')]
+        value = self.plugin.trait_value(match_list)
+        self.assertEqual(300, value)
+
+    def test_timedelta_precise_difference(self):
+        match_list = [('test.timestamp1', '2016-03-02T15:10:32.786893'),
+                      ('test.timestamp2', '2016-03-02T15:10:32.786899')]
+        value = self.plugin.trait_value(match_list)
+        self.assertEqual(0.000006, value)

ceilometer/tests/unit/meter/test_notifications.py

@@ -33,7 +33,9 @@ NOTIFICATION = {
     'timestamp': u'2015-06-1909: 19: 35.786893',
     'payload': {u'user_id': u'e1d870e51c7340cb9d555b15cbfcaec2',
                 u'resource_id': u'bea70e51c7340cb9d555b15cbfcaec23',
-                u'timestamp': u'2015-06-19T09: 19: 35.785330',
+                u'timestamp': u'2015-06-19T09:19:35.785330',
+                u'created_at': u'2015-06-19T09:25:35.785330',
+                u'launched_at': u'2015-06-19T09:25:40.785330',
                 u'message_signature': u'fake_signature1',
                 u'resource_metadata': {u'foo': u'bar'},
                 u'source': u'30be1fc9a03c4e94ab05c403a8a377f2: openstack',
@@ -455,6 +457,23 @@ class TestMeterProcessing(test.BaseTestCase):
         meta['event_type'] = NOTIFICATION['event_type']
         self.assertEqual(meta, s1['resource_metadata'])
 
+    def test_datetime_plugin(self):
+        cfg = yaml.dump(
+            {'metric': [dict(name="test1",
+                        event_type="test.*",
+                        type="gauge",
+                        unit="sec",
+                        volume={"fields": ["$.payload.created_at",
+                                           "$.payload.launched_at"],
+                                "plugin": "timedelta"},
+                        resource_id="$.payload.resource_id",
+                        project_id="$.payload.project_id")]})
+        self._load_meter_def_file(cfg)
+        c = list(self.handler.process_notification(NOTIFICATION))
+        self.assertEqual(1, len(c))
+        s1 = c[0].as_dict()
+        self.assertEqual(5.0, s1['volume'])
+
     def test_custom_metadata(self):
         cfg = yaml.dump(
             {'metric': [dict(name="test1",

setup.cfg

@@ -237,6 +237,8 @@ ceilometer.event.publisher =
 ceilometer.event.trait_plugin =
     split = ceilometer.event.trait_plugins:SplitterTraitPlugin
     bitfield = ceilometer.event.trait_plugins:BitfieldTraitPlugin
+    timedelta = ceilometer.event.trait_plugins:TimedeltaPlugin
+
 
 console_scripts =
     ceilometer-api = ceilometer.cmd.api:main