first pass ... the essentials

README.md

@@ -2,3 +2,6 @@ notification_utils
 ==================
 
 Utilities for dealing with OpenStack Notifications
+
+Includes datetime <-> Decimal conversion and Json marshalling handlers
+to name a few (for now)

notification_utils/__init__.py

@@ -0,0 +1,65 @@
+# Copyright (c) 2014 Dark Secret Software Inc.
+#
+# 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 calendar
+import collections
+import datetime
+import decimal
+import json
+
+
+def now():
+    """Broken out for testing."""
+    return datetime.datetime.utcnow()
+
+
+def dt_to_decimal(utc):
+    decimal.getcontext().prec = 30
+    return decimal.Decimal(str(calendar.timegm(utc.utctimetuple()))) + \
+           (decimal.Decimal(str(utc.microsecond)) /
+           decimal.Decimal("1000000.0"))
+
+
+def dt_from_decimal(dec):
+    if dec == None:
+        return "n/a"
+    integer = int(dec)
+    micro = (dec - decimal.Decimal(integer)) * decimal.Decimal(1000000)
+
+    daittyme = datetime.datetime.utcfromtimestamp(integer)
+    return daittyme.replace(microsecond=micro)
+
+
+class DateTimeEncoder(json.JSONEncoder):
+    def default(self, obj):
+        if isinstance(obj, datetime.datetime):
+            if obj.utcoffset() is not None:
+                obj = obj - obj.utcoffset()
+            return str(dt_to_decimal(obj))
+        return super(DateTimeEncoder, self).default(obj)
+
+
+# This is a hack for comparing structures load'ed from json
+# (which are always unicode) back to strings. It's used
+# for assertEqual() in the tests and is very slow and expensive.
+def unicode_to_string(data):
+    if isinstance(data, basestring):
+        return str(data)
+    elif isinstance(data, collections.Mapping):
+        return dict(map(unicode_to_string, data.iteritems()))
+    elif isinstance(data, collections.Iterable):
+        return type(data)(map(unicode_to_string, data))
+    else:
+        return data

requirements.txt

@@ -0,0 +1 @@
+dateutils

setup.cfg

@@ -0,0 +1,25 @@
+[metadata]
+name = notification_utils
+author = Dark Secret Software Inc.
+author-email = admin@darksecretsoftware.com
+summary = Utilities for dealing with OpenStack Notifications
+description-file = README.md
+license = Apache-2
+classifier =
+    Development Status :: 2 - Pre-Alpha
+        Environment :: Console
+        Intended Audience :: Developers
+        Intended Audience :: Information Technology
+        License :: OSI Approved :: Apache Software License
+        Operating System :: OS Independent
+        Programming Language :: Python
+        Topic :: Software Development :: Libraries :: Python Modules
+home-page = https://github.com/StackTach/notification_utils
+keywords =
+    openstack
+    notifications
+    events
+    utilities
+[files]
+packages =
+    notification_utils

setup.py

@@ -0,0 +1,8 @@
+#!/usr/bin/env python
+
+from setuptools import setup
+
+setup(
+    setup_requires=['pbr'],
+    pbr=True,
+)

test_requirements.txt

@@ -0,0 +1 @@
+nose

tests/test_utils.py

@@ -0,0 +1,43 @@
+import datetime
+import decimal
+import unittest
+
+import dateutil.tz
+
+import notification_utils
+
+
+class TestUtils(unittest.TestCase):
+    def setUp(self):
+        self.handler = notification_utils.DateTimeEncoder()
+
+    def test_handle_datetime_non_datetime(self):
+        self.assertRaises(TypeError, self.handler.default, "text")
+
+    def test_handle_datetime(self):
+        now = datetime.datetime(day=1, month=2, year=2014,
+                                hour=10, minute=11, second=12)
+        self.assertEqual("1391249472", self.handler.default(now))
+
+    def test_handle_datetime_offset(self):
+        now = datetime.datetime(day=1, month=2, year=2014,
+                                hour=10, minute=11, second=12,
+                                tzinfo=dateutil.tz.tzoffset(None, 4*60*60))
+        self.assertEqual("1391220672", self.handler.default(now))
+
+
+class TestDatetimeToDecimal(unittest.TestCase):
+    def test_datetime_to_decimal(self):
+        expected_decimal = decimal.Decimal('1356093296.123')
+        utc_datetime = datetime.datetime.utcfromtimestamp(expected_decimal)
+        actual_decimal = notification_utils.dt_to_decimal(utc_datetime)
+        self.assertEqual(actual_decimal, expected_decimal)
+
+    def test_decimal_to_datetime(self):
+        expected_decimal = decimal.Decimal('1356093296.123')
+        expected_datetime = datetime.datetime.utcfromtimestamp(expected_decimal)
+        actual_datetime = notification_utils.dt_from_decimal(expected_decimal)
+        self.assertEqual(actual_datetime, expected_datetime)
+
+    def test_dt_from_decimal_none(self):
+        self.assertEqual("n/a",notification_utils.dt_from_decimal(None))

tox.ini

@@ -0,0 +1,14 @@
+[tox]
+envlist = py26,py27
+
+[testenv]
+deps = 
+    -r{toxinidir}/requirements.txt
+    -r{toxinidir}/test_requirements.txt
+
+setenv = VIRTUAL_ENV={envdir}
+
+commands =
+   nosetests tests 
+
+sitepackages = False