Avoid using strtime for serializing datetimes

The timeutils module already provides a better
marshall/unmarshall routine that doesn't use strtime
but uses dictionary conversion instead so we should
just use that (to avoid the weirdness with strtime).

Change-Id: Ia7c88ec4266f914d0c89b67a3fb2b936cc1a1c93

3 files changed, 59 insertions, 7 deletions

diff --git a/oslo_serialization/msgpackutils.py b/oslo_serialization/msgpackutils.py
index 570e3a5..ac4f703 100644
--- a/oslo_serialization/msgpackutils.py
+++ b/oslo_serialization/msgpackutils.py
@@ -19,7 +19,7 @@ import uuid
 
 import msgpack
 from oslo_utils import importutils
-from oslo_utils import timeutils
+from pytz import timezone
 import six
 import six.moves.xmlrpc_client as xmlrpclib
 
@@ -34,14 +34,33 @@ else:
 
 
 def _serialize_datetime(dt):
-    blob = timeutils.strtime(dt)
-    if six.PY3:
-        return blob.encode('ascii')
-    return blob
+    dct = {
+        'day': dt.day,
+        'month': dt.month,
+        'year': dt.year,
+        'hour': dt.hour,
+        'minute': dt.minute,
+        'second': dt.second,
+        'microsecond': dt.microsecond,
+    }
+    if dt.tzinfo:
+        dct['tz'] = dt.tzinfo.tzname(None)
+    return dumps(dct)
 
 
 def _deserialize_datetime(blob):
-    return timeutils.parse_strtime(six.text_type(blob, encoding='ascii'))
+    dct = loads(blob)
+    dt = datetime.datetime(day=dct['day'],
+                           month=dct['month'],
+                           year=dct['year'],
+                           hour=dct['hour'],
+                           minute=dct['minute'],
+                           second=dct['second'],
+                           microsecond=dct['microsecond'])
+    if 'tz' in dct:
+        tzinfo = timezone(dct['tz'])
+        dt = tzinfo.localize(dt)
+    return dt
 
 
 def _serializer(obj):
diff --git a/requirements.txt b/requirements.txt
index eb6cf00..74ef925 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -10,3 +10,4 @@ msgpack-python>=0.4.0
 # library version this can be removed.
 iso8601>=0.1.9
 oslo.utils>=1.2.0                       # Apache-2.0
+pytz>=2013.6
diff --git a/tests/test_msgpackutils.py b/tests/test_msgpackutils.py
index 00c6c6b..8a9f965 100644
--- a/tests/test_msgpackutils.py
+++ b/tests/test_msgpackutils.py
@@ -19,6 +19,7 @@ import uuid
 
 import netaddr
 from oslotest import base as test_base
+from pytz import timezone
 import six
 import six.moves.xmlrpc_client as xmlrpclib
 import testtools
@@ -33,6 +34,9 @@ else:
     _PY26 = False
 
 
+_TZ_FMT = '%Y-%m-%d %H:%M:%S %Z%z'
+
+
 def _dumps_loads(obj):
     obj = msgpackutils.dumps(obj)
     return msgpackutils.loads(obj)
@@ -107,7 +111,7 @@ class MsgPackUtilsTestMixin(test_base.BaseTestCase):
         x = datetime.datetime(1920, 2, 3, 4, 5, 6, 7)
         self.assertEqual(_dumps_loads(x), x)
 
-    def test_DateTime(self):
+    def test_datetime(self):
         x = xmlrpclib.DateTime()
         x.decode("19710203T04:05:06")
         self.assertEqual(_dumps_loads(x), x)
@@ -115,3 +119,31 @@ class MsgPackUtilsTestMixin(test_base.BaseTestCase):
     def test_ipaddr(self):
         thing = {'ip_addr': netaddr.IPAddress('1.2.3.4')}
         self.assertEqual(_dumps_loads(thing), thing)
+
+    def test_datetime_tz_clone(self):
+        eastern = timezone('US/Eastern')
+        now = datetime.datetime.now()
+        e_dt = eastern.localize(now)
+        e_dt2 = _dumps_loads(e_dt)
+        self.assertEqual(e_dt, e_dt2)
+        self.assertEqual(e_dt.strftime(_TZ_FMT), e_dt2.strftime(_TZ_FMT))
+
+    def test_datetime_tz_different(self):
+        eastern = timezone('US/Eastern')
+        pacific = timezone('US/Pacific')
+        now = datetime.datetime.now()
+
+        e_dt = eastern.localize(now)
+        p_dt = pacific.localize(now)
+
+        self.assertNotEqual(e_dt, p_dt)
+        self.assertNotEqual(e_dt.strftime(_TZ_FMT), p_dt.strftime(_TZ_FMT))
+
+        e_dt2 = _dumps_loads(e_dt)
+        p_dt2 = _dumps_loads(p_dt)
+
+        self.assertNotEqual(e_dt2, p_dt2)
+        self.assertNotEqual(e_dt2.strftime(_TZ_FMT), p_dt2.strftime(_TZ_FMT))
+
+        self.assertEqual(e_dt, e_dt2)
+        self.assertEqual(p_dt, p_dt2)