pydantic dataclasses support

I saw prior issue https://github.com/tefra/xsdata/issues/522 and I’m using fastapi as well.

It looks like pydantic has support for standard dataclasses. https://pydantic-docs.helpmanual.io/usage/dataclasses/

This is easy enough to achieve in xsdata with a slight import change via build_import_patterns.

    @classmethod
    def build_import_patterns(cls) -> Dict[str, Dict]:
        type_patterns = cls.build_type_patterns
        return {
            "dataclasses": {"field": [" = field("]},
            "pydantic.dataclasses": {"dataclass": ["@dataclass"]},
            "decimal": {"Decimal": type_patterns("Decimal")},
            "enum": {"Enum": ["(Enum)"]},
            "typing": {
                "Dict": [": Dict"],
                "List": [": List["],
                "Optional": ["Optional["],
                "Tuple": ["Tuple["],
                "Type": ["Type["],
                "Union": ["Union["],
            },
            "xml.etree.ElementTree": {"QName": type_patterns("QName")},
            "xsdata.models.datatype": {
                "XmlDate": type_patterns("XmlDate"),
                "XmlDateTime": type_patterns("XmlDateTime"),
                "XmlDuration": type_patterns("XmlDuration"),
                "XmlPeriod": type_patterns("XmlPeriod"),
                "XmlTime": type_patterns("XmlTime"),
            },
        }

I don’t know if this 2 line change is worth an entire plugin or if it could be accomplished with a new output -o pydantic-dataclasses

[jtc42]

It’s still planned

Oh brilliant, and will this still be happening over at https://github.com/tefra/xsdata-pydantic ? Thanks!

Yeap, just out of curiocity what are the features of pydantic that you actually need or how do you plan to use xsdata with pydantic?

To be honest pydantic doesn’t play very nice with inner classes and forward referenceces and it’s a bit hard to work around these limitations…

For us, it’s really coming down to being able to do more complex validation on incoming XML files. We create our models using XSData which gives us some level of validation, but we want to do more complicated things like put limits on date ranges based on other data elsewhere in the model, or check data against something in an existing database, which we already have Pydantic-based code to do.

There’s other ways of achieving this though, it was more a case of this seems like a good starting point if it’s feasible on the XSData side, but if not we can work around it.

[jtc42]

It’s still planned

Oh brilliant, and will this still be happening over at https://github.com/tefra/xsdata-pydantic ?

Thanks!