improve iso8601 handling

graphene/core/types/custom_scalars.py

@@ -1,5 +1,6 @@
 import datetime
 import json
+import iso8601
 
 from graphql.core.language import ast
 
@@ -33,9 +34,8 @@ class DateTime(Scalar):
     @staticmethod
     def parse_literal(node):
         if isinstance(node, ast.StringValue):
-            return datetime.datetime.strptime(
-                node.value, "%Y-%m-%dT%H:%M:%S.%f")
+            return iso8601.parse_date(node.value)
 
     @staticmethod
     def parse_value(value):
-        return datetime.datetime.strptime(value, "%Y-%m-%dT%H:%M:%S.%f")
+        return iso8601.parse_date(value)

graphene/core/types/tests/test_custom_scalars.py

@@ -0,0 +1,27 @@
+import iso8601
+
+from graphql.core.language.ast import StringValue
+
+from ..custom_scalars import DateTime
+
+def test_date_time():
+    test_iso_string = "2016-04-29T18:34:12.502Z"
+
+    def check_datetime(test_dt):
+        assert test_dt.tzinfo == iso8601.UTC
+        assert test_dt.year == 2016
+        assert test_dt.month == 04
+        assert test_dt.day == 29
+        assert test_dt.hour == 18
+        assert test_dt.minute == 34
+        assert test_dt.second == 12
+
+    test_dt = DateTime().parse_value(test_iso_string)
+    check_datetime(test_dt)
+
+    assert DateTime.serialize(test_dt) == "2016-04-29T18:34:12.502000+00:00"
+
+    node = StringValue(test_iso_string)
+    test_dt = DateTime.parse_literal(node)
+    check_datetime(test_dt)
+

setup.py

@@ -57,6 +57,7 @@ setup(
         'six>=1.10.0',
         'graphql-core>=0.4.9',
         'graphql-relay==0.3.3',
+        'iso8601==0.1.11',
     ],
     tests_require=[
         'django-filter>=0.10.0',