ignore unknown properties in nested classes. How to propagate schema config to nested classes?

[lidatong]

ignore unknown properties in nested classes. How to propagate schema config to nested classes?

[arturstorm]

@nathan5280, thanks for answer!
It will be grate to have functionality like in Jakson(java lib) @JsonIgnoreProperties(ignoreUnknown = true):

@dataclass_json(unknown=EXCLUDE)
@dataclass(frozen=True)
class Minion:
    name: str

[nathan5280]

I've started poking around with dataclasses-json as a replacement for my homegrown version of this functionality and anticipate running into this issue. I haven't had a chance to look at how to solve this cleanly, but came up with this work around. It wouldn't be too hard to do this recursively.

from dataclasses import dataclass
from dataclasses_json import dataclass_json
from typing import List

from marshmallow import EXCLUDE, ValidationError


@dataclass_json
@dataclass(frozen=True)
class Minion:
    name: str


@dataclass_json
@dataclass(frozen=True)
class Boss:
    minions: List[Minion]


boss_json = """
{
    "minions": [
        {
            "name": "evil minion", 
            "UNKNOWN_PROPERTY" : "value"
        },
        {
            "name": "very evil minion"
        }
    ],
    "UNKNOWN_PROPERTY" : "value"
}
""".strip()


def main():
    boss_schema = Boss.schema(unknown=EXCLUDE)
    try:
        boss_schema.loads(boss_json, unknown="exclude")
    except ValidationError:
        pass

    boss_schema.fields["minions"].container.unknown = EXCLUDE
    boss = boss_schema.loads(boss_json)
    print(boss)


if __name__ == "__main__":
    main()

What I've done is to generate the Boss Schema and then go in and get the nested Minion Schema and change it's unknown attribute to EXCLUDE. This now runs cleanly and gets the Expected result.

[r-richmond]

At the risk of being too verbose and exposing some potential ignorance, I'd just like to say

1. Awesome project lidatong
2. The functionality arturstorm describes would also be amazing; in my case I'm only interested in some high-level portions of a rest-api response but based on my understanding of the project I had to completely type out the entire response to use dataclass_json.

[RunOrVeith]

I will submit a pull request for a general solution to this.
I have it working using the from_dict methods, but not the schema yet. But I think I know how to add it there as well, I will look at that tomorrow.

There will be options such as

@dataclass_json(undefined_parameters=UndefinedParameters.EXCLUDE)
@dataclass_json(undefined_parameters=UndefinedParameters.RAISE)
@dataclass_json(undefined_parameters=UndefinedParameters.INCLUDE)

I'll link the pull request here when I make it.