Merge "Add noop metrics client"

designate/metrics.py

@@ -37,7 +37,11 @@ Usage examples:
 
 """
 
-import monascastatsd
+try:
+    import monascastatsd as stats_client
+except Exception:
+    import designate.metrics_client.noop as stats_client
+
 from oslo_config import cfg
 from oslo_log import log as logging
 
@@ -67,7 +71,7 @@ class Metrics(object):
         """Initialize Monasca-Statsd client with its default configuration.
         Do not start sending metrics yet.
         """
-        self._client = monascastatsd.Client(dimensions={
+        self._client = stats_client.Client(dimensions={
             'service_name': 'dns'
         })
         # cfg.CONF is not available at this time

designate/metrics_client/noop.py

@@ -0,0 +1,90 @@
+#
+# Copyright (C) 2016 Red Hat, 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.
+#
+
+from designate.i18n import _LE
+
+from oslo_log import log as logging
+
+LOG = logging.getLogger(__name__)
+
+
+class NoopConnection(object):
+    def __init__(self):
+        pass
+
+    def _flush_buffer(self):
+        pass
+
+    def close_buffer(self):
+        pass
+
+    def connect(self, *a, **kw):
+        LOG.error(_LE('Using noop metrics client. Metrics will be ignored.'))
+        pass
+
+    def open_buffer(self):
+        pass
+
+
+class NoopCounter(object):
+    def __init__(self):
+        pass
+
+    def increment(self, *a, **kw):
+        pass
+
+    def decrement(self, *a, **kw):
+        pass
+
+    def __add__(self, value):
+        pass
+
+    def __sub__(self, value):
+        pass
+
+
+class NoopGuage(object):
+    def __init__(self):
+        pass
+
+    def send(self, *a, **kw):
+        pass
+
+
+class NoopTimer(object):
+    def __init__(self):
+        pass
+
+    def timed(self, *a, **kw):
+        pass
+
+
+class Client(object):
+    def __init__(self, *a, **kw):
+        self._counter = NoopCounter()
+        self._guage = NoopGuage()
+        self._timer = NoopTimer()
+        self.connection = NoopConnection()
+        pass
+
+    def get_counter(self, *a, **kw):
+        return None
+
+    def get_guage(self, *a, **kw):
+        return None
+
+    def get_timer(self):
+        return None

designate/tests/unit/test_metrics/test_metrics.py

@@ -0,0 +1,45 @@
+#
+# Copyright (C) 2016 Red Hat, 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 designate.metrics import Metrics
+from designate.metrics_client import noop
+from designate.tests import TestCase
+
+from oslo_config import cfg
+from oslo_config import fixture as cfg_fixture
+
+
+class TestNoopMetrics(TestCase):
+
+    def setUp(self):
+        super(TestCase, self).setUp()
+        self.CONF = self.useFixture(cfg_fixture.Config(cfg.CONF)).conf
+        self.metrics = Metrics()
+        self.metrics._client = noop.Client()
+
+    def test_noop_metrics_enabled(self):
+        self.CONF.set_override('enabled', True, 'monasca:statsd')
+        with mock.patch('designate.metrics_client.noop.LOG') as log_mock:
+            self.metrics.init()
+            log_mock.error.assert_called_once_with(
+                "Using noop metrics client. Metrics will be ignored.")
+
+    def test_noop_metrics_disabled(self):
+        with mock.patch('designate.metrics_client.noop.LOG') as log_mock:
+            self.metrics.init()
+            log_mock.error.assert_not_called()