Add Metrics: LabelKey and LabelValue (#336)

* Add Metrics: LabelKey and LabelValue

* Fix tests

Author: mayurkale22

opencensus/metrics/__init__.py

@@ -0,0 +1,37 @@
+# Copyright 2018, OpenCensus Authors
+#
+# 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.
+
+
+class LabelKey(object):
+    """The label keys associated with the metric descriptor.
+
+    :type key: str
+    :param key: the key for the label
+
+    :type description: str
+    :param description: description of the label
+    """
+    def __init__(self, key, description):
+        self._key = key
+        self._description = description
+
+    @property
+    def key(self):
+        """the key for the label"""
+        return self._key
+
+    @property
+    def description(self):
+        """a human-readable description of what this label key represents"""
+        return self._description

opencensus/metrics/label_key.py

@@ -0,0 +1,28 @@
+# Copyright 2018, OpenCensus Authors
+#
+# 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.
+
+
+class LabelValue(object):
+    """The label values associated with the TimeSeries.
+
+    :type value: str
+    :param value: the value for the label
+    """
+    def __init__(self, value=None):
+        self._value = value
+
+    @property
+    def value(self):
+        """the value for the label"""
+        return self._value

opencensus/metrics/label_value.py

@@ -0,0 +1,48 @@
+# -*- coding: utf-8 -*-
+
+# Copyright 2018, OpenCensus Authors
+#
+# 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 unittest
+from opencensus.metrics import label_key as label_key_module
+
+
+class TestLabelKey(unittest.TestCase):
+
+    def test_constructor(self):
+        key = 'key1'
+        description = 'description1'
+        label_key = label_key_module.LabelKey(key, description)
+
+        self.assertIsNotNone(label_key)
+        self.assertEqual(label_key.key, key)
+        self.assertEqual(label_key.description, description)
+
+    def test_constructor_Empty(self):
+        key = ''
+        description = ''
+        label_key = label_key_module.LabelKey(key, description)
+
+        self.assertIsNotNone(label_key)
+        self.assertEqual(label_key.key, '')
+        self.assertEqual(label_key.description, '')
+
+    def test_constructor_WithNonAsciiChars(self):
+        key = '值'
+        description = '测试用键'
+        label_key = label_key_module.LabelKey(key, description)
+
+        self.assertIsNotNone(label_key)
+        self.assertEqual(label_key.key, key)
+        self.assertEqual(label_key.description, description)

tests/unit/metrics/test_label_key.py

@@ -0,0 +1,48 @@
+# -*- coding: utf-8 -*-
+
+# Copyright 2018, OpenCensus Authors
+#
+# 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 unittest
+from opencensus.metrics import label_value as label_value_module
+
+
+class TestLabelValue(unittest.TestCase):
+
+    def test_constructor(self):
+        value = 'value1'
+        label_value = label_value_module.LabelValue(value)
+
+        self.assertIsNotNone(label_value)
+        self.assertEqual(label_value.value, value)
+
+    def test_constructor_None(self):
+        label_value = label_value_module.LabelValue()
+
+        self.assertIsNotNone(label_value)
+        self.assertIsNone(label_value.value)
+
+    def test_constructor_Empty(self):
+        value = ''
+        label_value = label_value_module.LabelValue(value)
+
+        self.assertIsNotNone(label_value)
+        self.assertEquals(label_value.value, '')
+
+    def test_constructor_WithNonAsciiChars(self):
+        value = '值'
+        label_value = label_value_module.LabelValue(value)
+
+        self.assertIsNotNone(label_value)
+        self.assertEquals(label_value.value, value)