Add time- and version-stamps to created objects

.idea/misc.xml

@@ -54,7 +54,7 @@
     <ConfirmationsSetting value="0" id="Add" />
     <ConfirmationsSetting value="0" id="Remove" />
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_3" default="false" assert-keyword="false" jdk-15="false" project-jdk-name="Python 2.7.12 virtualenv at ~/Development/metrik/py2-virt" project-jdk-type="Python SDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_3" default="false" assert-keyword="false" jdk-15="false" project-jdk-name="Python 3.5.1 virtualenv at C:\Users\Bradlee Speice\Development\metrik\metrik-virtual" project-jdk-type="Python SDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
   <component name="PythonCompatibilityInspectionAdvertiser">

metrik/__init__.py

@@ -1,2 +1,2 @@
-__version__ = '0.4.1'
+__version__ = '0.4.2'
 __release__ = __version__

metrik/targets/mongo.py

@@ -4,6 +4,7 @@ from datetime import datetime
 from contextlib import contextmanager
 
 from metrik.conf import get_config
+from metrik import __version__ as version
 
 
 class MongoTarget(Target):
@@ -29,9 +30,12 @@ class MongoTarget(Target):
                 '_id': self.id
             }) is not None
 
-    def persist(self, dict_object):
+    def persist(self, dict_object, present=None):
         id_dict = dict_object
         id_dict['_id'] = self.id
+        id_dict['_metrik_version'] = version
+        id_dict['_created_at'] = (present if present is not None
+                                  else datetime.now())
 
         with self.get_db() as db:
             return db[self.collection].insert_one(id_dict).inserted_id

test/targets/test_mongo_target.py

@@ -1,10 +1,11 @@
 from pymongo import MongoClient
 from random import randint
+from datetime import datetime, timedelta
 
 from metrik.targets.mongo import MongoTarget
 from metrik.conf import get_config
 from test.mongo_test import MongoTest
-
+from metrik import __version__ as version
 
 class MongoTargetTest(MongoTest):
 
@@ -39,3 +40,22 @@ class MongoTargetTest(MongoTest):
         targets = [MongoTarget('test_collection', i) for i in range(10000)]
 
         self.assertEqual(len(targets), 10000)
+
+    def test_metrik_version_saved(self):
+        t = MongoTarget('test_collection', 1234)
+        t.persist({})
+        r = t.retrieve()
+        assert r['_metrik_version'] == version
+
+    def test_created_at_timestamp(self):
+        present = datetime.now()
+        t = MongoTarget('test_collection', 1234)
+        t.persist({})
+        r = t.retrieve()
+        self.assertGreaterEqual(present, r['_created_at'])
+
+        one_second_past = present - timedelta(seconds=1)
+        t = MongoTarget('test_collection', 1235)
+        t.persist({}, present=one_second_past)
+        r = t.retrieve()
+        self.assertEqual(one_second_past, r['_created_at'])