model: fix edge case for Edm.DateTimeOffset.from_json() without offset

CHANGELOG.md

@@ -6,6 +6,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 
+- model: fix edge case for Edm.DateTimeOffset.from_json() without offset - Petr Hanak
+
 ## [1.10.0]
 
 ### Added

pyodata/v2/model.py

@@ -529,6 +529,12 @@ def to_json(self, value):
         return f'/Date({ticks}{offset_in_minutes:+05})/'
 
     def from_json(self, value):
+        # special edge case:
+        # datetimeoffset'yyyy-mm-ddThh:mm[:ss]' = defaults to UTC, when offset value is not provided in responde data by service but the metadata is EdmDateTimeOffset
+        # intentionally just for from_json, generation of to_json should always provide timezone info
+        if re.match(r"^/Date\((?P<milliseconds_since_epoch>-?\d+)\)/$", value):
+            value = value.replace(')', '+0000)')
+
         matches = re.match(r"^/Date\((?P<milliseconds_since_epoch>-?\d+)(?P<offset_in_minutes>[+-]\d+)\)/$", value)
         try:
             milliseconds_since_epoch = matches.group('milliseconds_since_epoch')

tests/test_model_v2.py

@@ -690,6 +690,9 @@ def test_traits_datetimeoffset(type_date_time_offset):
 def test_traits_datetimeoffset_to_literal(type_date_time_offset):
     """Test Edm.DateTimeOffset trait: Python -> literal"""
 
+    testdate = datetime(1, 1, 1, 0, 0, 0, 0, tzinfo=timezone.utc)
+    assert type_date_time_offset.traits.to_literal(testdate) == "datetimeoffset'0001-01-01T00:00:00+00:00'"
+
     testdate = datetime(2005, 1, 28, 18, 30, 44, 123456, tzinfo=timezone(timedelta(hours=3, minutes=40)))
     assert type_date_time_offset.traits.to_literal(testdate) == "datetimeoffset'2005-01-28T18:30:44.123456+03:40'"
 
@@ -746,7 +749,7 @@ def test_traits_datetimeoffset_from_invalid_literal(type_date_time_offset):
     assert str(e_info.value).startswith('Cannot decode datetimeoffset from value xyz')
 
 
-def test_traits_datetimeoffset_from_odata(type_date_time_offset):
+def test_traits_datetimeoffset_from_json(type_date_time_offset):
     """Test Edm.DateTimeOffset trait: OData -> Python"""
 
     # parsing full representation
@@ -768,6 +771,14 @@ def test_traits_datetimeoffset_from_odata(type_date_time_offset):
     assert testdate.microsecond == 0
     assert testdate.tzinfo == timezone(-timedelta(minutes=5))
 
+    # parsing special edge case with no offset provided, defaults to UTC
+    testdate = type_date_time_offset.traits.from_json("/Date(217567986000)/")
+    assert testdate.year == 1976
+    assert testdate.minute == 33
+    assert testdate.second == 6
+    assert testdate.microsecond == 0
+    assert testdate.tzinfo == timezone.utc
+
     # parsing below lowest value with workaround
     pyodata.v2.model.FIX_SCREWED_UP_MINIMAL_DATETIME_VALUE = True
     testdate = type_date_time_offset.traits.from_json("/Date(-62135596800001+0001)/")