Merge pull request #200 from Scille/fix_reference_round-trip

Let Reference and GenericReference round-trip

tests/test_marshmallow.py

@@ -432,9 +432,15 @@ class Doc(Document):
         # schema to OO world
         ma_schema_cls = Doc.schema.as_marshmallow_schema()
         ma_schema = ma_schema_cls()
+        # Dump uMongo object
         ret = ma_schema.dump(doc)
         assert not ret.errors
         assert ret.data == serialized
+        # Dump OO data (not uMongo object) to ensure bonus fields round-trip
+        ret = ma_schema.dump(oo_data)
+        assert not ret.errors
+        assert ret.data == serialized
+        # Load serialized data
         ret = ma_schema.load(serialized)
         assert not ret.errors
         assert ret.data == oo_data

umongo/marshmallow_bonus.py

@@ -149,6 +149,9 @@ def _serialize(self, value, attr, obj):
             return str(value)
         else:
             # In OO world, value is a :class:`umongo.data_object.Reference`
+            # or an ObjectId before being loaded into a Document
+            if isinstance(value, bson.ObjectId):
+                return str(value)
             return str(value.pk)
 
 
@@ -169,6 +172,9 @@ def _serialize(self, value, attr, obj):
             return {'id': str(value['_id']), 'cls': value['_cls']}
         else:
             # In OO world, value is a :class:`umongo.data_object.Reference`
+            # or a dict before being loaded into a Document
+            if isinstance(value, dict):
+                return {'id': str(value['id']), 'cls': value['cls']}
             return {'id': str(value.pk), 'cls': value.document_cls.__name__}
 
     def _deserialize(self, value, attr, data):