Fix for timezones (singer-io#35)

karstendick · web-flow · commit 47af0fc20e4a · 2017-08-14T11:07:21.000-04:00
* bump version

* timezone or bust

* added unit tests
diff --git a/setup.py b/setup.py
@@ -4,14 +4,15 @@
 import subprocess
 
 setup(name="singer-python",
-      version='2.1.4',
+      version='3.0.0',
       description="Singer.io utility library",
       author="Stitch",
       classifiers=['Programming Language :: Python :: 3 :: Only'],
       url="http://singer.io",
       install_requires=[
           'pendulum==1.2.0',
           'simplejson==3.11.1',
+          'python-dateutil==2.6.0',
       ],
       packages=find_packages(),
       package_data = {
diff --git a/singer/transform.py b/singer/transform.py
@@ -25,11 +25,11 @@ def string_to_datetime(value):
 
 
 def unix_milliseconds_to_datetime(value):
-    return strftime(datetime.datetime.utcfromtimestamp(int(value) * 0.001))
+    return strftime(datetime.datetime.fromtimestamp(int(value) * 0.001, datetime.timezone.utc))
 
 
 def unix_seconds_to_datetime(value):
-    return strftime(datetime.datetime.utcfromtimestamp(int(value)))
+    return strftime(datetime.datetime.fromtimestamp(int(value), datetime.timezone.utc))
 
 
 class SchemaMismatch(Exception):
diff --git a/singer/utils.py b/singer/utils.py
@@ -4,22 +4,27 @@
 import functools
 import json
 import time
+import dateutil
 
 from singer.catalog import Catalog
 
 DATETIME_PARSE = "%Y-%m-%dT%H:%M:%SZ"
 DATETIME_FMT = "%Y-%m-%dT%H:%M:%S.%fZ"
 
 
+def strptime_with_tz(dtime):
+    return dateutil.parser.parse(dtime)
+
 def strptime(dtime):
     try:
         return datetime.datetime.strptime(dtime, DATETIME_FMT)
     except Exception:
         return datetime.datetime.strptime(dtime, DATETIME_PARSE)
 
 def strftime(dtime):
-    return dtime.strftime(DATETIME_FMT)
-
+    if dtime.utcoffset() != datetime.timedelta(0):
+        raise Exception("datetime must be pegged at UTC tzoneinfo")
+    return dtime.strftime("%Y-%m-%dT%H:%M:%S.%fZ")
 
 def ratelimit(limit, every):
     def limitdecorator(func):
diff --git a/tests/test_transform.py b/tests/test_transform.py
@@ -206,3 +206,11 @@ def test_unexpected_object_properties(self):
         self.assertDictEqual({"good_property": "expected data"}, transformed_data)
         self.assertSetEqual(set(["bad_property"]), trans.removed)
         self.assertListEqual([], trans.errors)
+
+    def test_unix_seconds_to_datetime(self):
+        self.assertEqual(unix_seconds_to_datetime(0), '1970-01-01T00:00:00.000000Z')
+        self.assertEqual(unix_seconds_to_datetime(1502722441), '2017-08-14T14:54:01.000000Z')
+
+    def test_unix_seconds_to_datetime(self):
+        self.assertEqual(unix_milliseconds_to_datetime(0), '1970-01-01T00:00:00.000000Z')
+        self.assertEqual(unix_milliseconds_to_datetime(1502722441000), '2017-08-14T14:54:01.000000Z')
