Custom class factory¶

The philosophy behind xsdata is to have plain objects without additional methods and logic. If you need an entry point to add any pre/post initialization logic or even validations you can use the parser config to override the default class factory.

>>> from dataclasses import dataclass
>>> from xsdata.formats.dataclass.parsers import JsonParser
>>> from xsdata.formats.dataclass.parsers.config import ParserConfig
...
>>> def custom_class_factory(clazz, params):
...     if clazz.__name__ == "Person":
...         return clazz(**{k: v.upper() for k, v in params.items()})
...
...     return clazz(**params)
...

>>> config = ParserConfig(class_factory=custom_class_factory)
>>> parser = JsonParser(config=config)
...
>>> @dataclass
... class Person:
...     first_name: str
...     last_name: str
...
>>> json_str = """{"first_name": "chris", "last_name": "foo"}"""
...
...
>>> print(parser.from_string(json_str, Person))
Person(first_name='CHRIS', last_name='FOO')

Warning

It’s not recommended to modify the generated models!