nillable fields are skipped by XmlSerializer

Hi,

I have nillable=“true” in my xsd. I generated a python class for this xsd. I serialize the class into xml using XmlSerializer. My problem is that the nillable field is missing in the xml. I have

            "required": True,
            "nillable": True,

in the generated code for the nillable field. So I think that XmlSerializer should generate an empty tag for this field.

I don’t know if it’s a bug or not. Could you please suggest.

More details:

I created a small repo to reproduce: https://github.com/barsv/xsdata-issue.git

My test.xsd file:

<?xml version="1.0" encoding="UTF-8" ?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">

<xs:element name="shiporder">
  <xs:complexType>
    <xs:sequence>
      <xs:element minOccurs="1" maxOccurs="1" name="name" nillable="true" type="xs:string"/>
    </xs:sequence>
  </xs:complexType>
</xs:element>

</xs:schema>

I generated test.py using xsdata test.xsd:

@dataclass
class Shiporder:
    class Meta:
        name = "shiporder"

    name: Optional[str] = field(
        default=None,
        metadata={
            "type": "Element",
            "namespace": "",
            "required": True,
            "nillable": True,
        }
    )

I serialize it using the following code:

config = SerializerConfig(pretty_print=True)
xml_serializer = XmlSerializer(config=config)

order = Shiporder()
#order.name = "test"
xml = xml_serializer.render(order)
print(xml)

and I get the following xml:

<?xml version="1.0" encoding="UTF-8"?>
<shiporder/>

This xml doesn’t pass validation against the original xsd.

I would expect to get the following xml instead:

<?xml version="1.0" encoding="UTF-8"?>
<shiporder>
    <name/>
</shiporder>

ps: I’m not an expert in neither xsd nor python.

[tefra]

Thank you for reporting @barsv the fix is on master and will be included in the next release.

[tefra]

No leave it open I am planning to change this behavior in the next release, to avoid the empty string hack I just need to test a few more things