adds tagging support for cloudwatch events service

tests/test_utilities/test_tagging_service.py

@@ -0,0 +1,53 @@
+import unittest
+
+from moto.utilities.tagging_service import TaggingService
+
+
+class TestTaggingService(unittest.TestCase):
+    def test_list_empty(self):
+        svc = TaggingService()
+        result = svc.list_tags_for_resource('test')
+        self.assertEqual(result, {'Tags': []})
+
+    def test_create_tag(self):
+        svc = TaggingService('TheTags', 'TagKey', 'TagValue')
+        tags = [{'TagKey': 'key_key', 'TagValue': 'value_value'}]
+        svc.tag_resource('arn', tags)
+        actual = svc.list_tags_for_resource('arn')
+        expected = {'TheTags': [{'TagKey': 'key_key', 'TagValue': 'value_value'}]}
+        self.assertDictEqual(expected, actual)
+
+    def test_create_tag_without_value(self):
+        svc = TaggingService()
+        tags = [{'Key': 'key_key'}]
+        svc.tag_resource('arn', tags)
+        actual = svc.list_tags_for_resource('arn')
+        expected = {'Tags': [{'Key': 'key_key', 'Value': ''}]}
+        self.assertDictEqual(expected, actual)
+
+    def test_delete_tag(self):
+        svc = TaggingService()
+        tags = [{'Key': 'key_key', 'Value': 'value_value'}]
+        svc.tag_resource('arn', tags)
+        svc.untag_resource('arn', ['key_key'])
+        result = svc.list_tags_for_resource('arn')
+        self.assertEqual(
+            result, {'Tags': []})
+
+    def test_list_empty_delete(self):
+        svc = TaggingService()
+        svc.untag_resource('arn', ['key_key'])
+        result = svc.list_tags_for_resource('arn')
+        self.assertEqual(
+            result, {'Tags': []})
+
+    def test_extract_tag_names(self):
+        svc = TaggingService()
+        tags = [{'Key': 'key1', 'Value': 'value1'}, {'Key': 'key2', 'Value': 'value2'}]
+        actual = svc.extract_tag_names(tags)
+        expected = ['key1', 'key2']
+        self.assertEqual(expected, actual)
+
+
+if __name__ == '__main__':
+    unittest.main()