Add unit tests for common rest.utils module

Add unit tests for common json conversions and exception handling.

Change-Id: I71ab992bb09114f4fd9c9752820ab57b4c51577a

monasca_common/tests/test_rest.py

@@ -0,0 +1,79 @@
+# Copyright 2016 OpenStack Foundation
+#
+# 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
+import unittest
+
+from monasca_common.rest.exceptions import DataConversionException
+from monasca_common.rest.exceptions import UnreadableContentError
+from monasca_common.rest.exceptions import UnsupportedContentTypeException
+from monasca_common.rest import utils
+
+
+class TestRestUtils(unittest.TestCase):
+
+    def setUp(self):
+        self.mock_json_patcher = mock.patch('monasca_common.rest.utils.json')
+        self.mock_json = self.mock_json_patcher.start()
+
+    def tearDown(self):
+        self.mock_json_patcher.stop()
+
+    def test_read_body_with_success(self):
+        self.mock_json.loads.return_value = ""
+        payload = mock.Mock()
+
+        utils.read_body(payload)
+
+        self.mock_json.loads.assert_called_once_with(payload.read.return_value)
+
+    def test_read_body_empty_content_in_payload(self):
+        self.mock_json.loads.return_value = ""
+        payload = mock.Mock()
+        payload.read.return_value = None
+
+        self.assertIsNone(utils.read_body(payload))
+
+    def test_read_body_json_loads_exception(self):
+        self.mock_json.loads.side_effect = Exception
+        payload = mock.Mock()
+
+        self.assertRaises(DataConversionException, utils.read_body, payload)
+
+    def test_read_body_unsupported_content_type(self):
+        unsupported_content_type = mock.Mock()
+
+        self.assertRaises(
+            UnsupportedContentTypeException, utils.read_body, None,
+            unsupported_content_type)
+
+    def test_read_body_unreadable_content_error(self):
+        unreadable_content = mock.Mock()
+        unreadable_content.read.side_effect = Exception
+
+        self.assertRaises(
+            UnreadableContentError, utils.read_body, unreadable_content)
+
+    def test_as_json_success(self):
+        data = mock.Mock()
+
+        dumped_json = utils.as_json(data)
+
+        self.assertEqual(dumped_json, self.mock_json.dumps.return_value)
+
+    def test_as_json_with_exception(self):
+        data = mock.Mock()
+        self.mock_json.dumps.side_effect = Exception
+
+        self.assertRaises(DataConversionException, utils.as_json, data)